merge multiple repositories into an existing monorepo

- merged using: 'monorepo_add.sh services-filestore:services/filestore'
- see https://github.com/shopsys/monorepo-tools

services/filestore/.dockerignore

@@ -0,0 +1,10 @@
+node_modules/*
+gitrev
+.git
+.gitignore
+.npm
+.nvmrc
+nodemon.json
+uploads/
+user_files/
+template_files/

services/filestore/.eslintrc

@@ -0,0 +1,86 @@
+// this file was auto-generated, do not edit it directly.
+// instead run bin/update_build_scripts from
+// https://github.com/sharelatex/sharelatex-dev-environment
+{
+  "extends": [
+    "eslint:recommended",
+    "standard",
+    "prettier"
+  ],
+  "parserOptions": {
+    "ecmaVersion": 2018
+  },
+  "plugins": [
+    "mocha",
+    "chai-expect",
+    "chai-friendly"
+  ],
+  "env": {
+    "node": true,
+    "mocha": true
+  },
+  "rules": {
+    // TODO(das7pad): remove overrides after fixing all the violations manually (https://github.com/overleaf/issues/issues/3882#issuecomment-878999671)
+    // START of temporary overrides
+    "array-callback-return": "off",
+    "no-dupe-else-if": "off",
+    "no-var": "off",
+    "no-empty": "off",
+    "node/handle-callback-err": "off",
+    "no-loss-of-precision": "off",
+    "node/no-callback-literal": "off",
+    "node/no-path-concat": "off",
+    "prefer-regex-literals": "off",
+    // END of temporary overrides
+
+    // Swap the no-unused-expressions rule with a more chai-friendly one
+    "no-unused-expressions": 0,
+    "chai-friendly/no-unused-expressions": "error",
+
+    // Do not allow importing of implicit dependencies.
+    "import/no-extraneous-dependencies": "error"
+  },
+  "overrides": [
+    {
+      // Test specific rules
+      "files": ["test/**/*.js"],
+      "globals": {
+        "expect": true
+      },
+      "rules": {
+        // mocha-specific rules
+        "mocha/handle-done-callback": "error",
+        "mocha/no-exclusive-tests": "error",
+        "mocha/no-global-tests": "error",
+        "mocha/no-identical-title": "error",
+        "mocha/no-nested-tests": "error",
+        "mocha/no-pending-tests": "error",
+        "mocha/no-skipped-tests": "error",
+        "mocha/no-mocha-arrows": "error",
+
+        // chai-specific rules
+        "chai-expect/missing-assertion": "error",
+        "chai-expect/terminating-properties": "error",
+
+        // prefer-arrow-callback applies to all callbacks, not just ones in mocha tests.
+        // we don't enforce this at the top-level - just in tests to manage `this` scope
+        // based on mocha's context mechanism
+        "mocha/prefer-arrow-callback": "error"
+      }
+    },
+    {
+      // Backend specific rules
+      "files": ["app/**/*.js", "app.js", "index.js"],
+      "rules": {
+        // don't allow console.log in backend code
+        "no-console": "error",
+
+        // Do not allow importing of implicit dependencies.
+        "import/no-extraneous-dependencies": ["error", {
+          // Do not allow importing of devDependencies.
+          "devDependencies": false
+        }]
+      }
+    }
+  ]
+}

services/filestore/.github/ISSUE_TEMPLATE.md

@@ -0,0 +1,38 @@
+<!-- BUG REPORT TEMPLATE -->
+
+## Steps to Reproduce
+<!-- Describe the steps leading up to when / where you found the bug. -->
+<!-- Screenshots may be helpful here. -->
+
+1.
+2.
+3.
+
+## Expected Behaviour
+<!-- What should have happened when you completed the steps above? -->
+
+## Observed Behaviour
+<!-- What actually happened when you completed the steps above? -->
+<!-- Screenshots may be helpful here. -->
+
+## Context
+<!-- How has this issue affected you? What were you trying to accomplish? -->
+
+## Technical Info
+<!-- Provide any technical details that may be applicable (or N/A if not applicable). -->
+
+* URL:
+* Browser Name and version:
+* Operating System and version (desktop or mobile):
+* Signed in as:
+* Project and/or file:
+
+## Analysis
+<!--- Optionally, document investigation of / suggest a fix for the bug, e.g. 'comes from this line / commit' -->
+
+## Who Needs to Know?
+<!-- If you want to bring this to the attention of particular people, @-mention them below. -->
+<!-- If a user reported this bug and should be notified when it is fixed, provide the Front conversation link. -->
+
+-
+-

services/filestore/.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,48 @@
+
+<!-- ** This is an Overleaf public repository ** -->
+
+<!-- Please review https://github.com/overleaf/overleaf/blob/master/CONTRIBUTING.md for guidance on what is expected of a contribution. -->
+
+### Description
+
+
+
+#### Screenshots
+
+
+
+#### Related Issues / PRs
+
+
+
+### Review
+
+
+
+#### Potential Impact
+
+
+
+#### Manual Testing Performed
+
+- [ ]
+- [ ]
+
+#### Accessibility
+
+
+
+### Deployment
+
+
+
+#### Deployment Checklist
+
+- [ ] Update documentation not included in the PR (if any)
+- [ ]
+
+#### Metrics and Monitoring
+
+
+
+#### Who Needs to Know?

services/filestore/.github/dependabot.yml

@@ -0,0 +1,23 @@
+version: 2
+updates:
+  - package-ecosystem: "npm"
+    directory: "/"
+    schedule:
+      interval: "daily"
+
+    pull-request-branch-name:
+      # Separate sections of the branch name with a hyphen
+      # Docker images use the branch name and do not support slashes in tags
+      # https://github.com/overleaf/google-ops/issues/822
+      # https://docs.github.com/en/github/administering-a-repository/configuration-options-for-dependency-updates#pull-request-branch-nameseparator
+      separator: "-"
+
+    # Block informal upgrades -- security upgrades use a separate queue.
+    # https://docs.github.com/en/github/administering-a-repository/configuration-options-for-dependency-updates#open-pull-requests-limit
+    open-pull-requests-limit: 0
+
+    # currently assign team-magma to all dependabot PRs - this may change in
+    # future if we reorganise teams
+    labels:
+      - "dependencies"
+      - "type:maintenance"

services/filestore/.gitignore

@@ -0,0 +1,54 @@
+compileFolder
+
+Compiled source #
+###################
+*.com
+*.class
+*.dll
+*.exe
+*.o
+*.so
+
+# Packages #
+############
+# it's better to unpack these files and commit the raw source
+# git has its own built in compression methods
+*.7z
+*.dmg
+*.gz
+*.iso
+*.jar
+*.rar
+*.tar
+*.zip
+
+# Logs and databases #
+######################
+*.log
+*.sql
+*.sqlite
+
+# OS generated files #
+######################
+.DS_Store?
+ehthumbs.db
+Icon?
+Thumbs.db
+
+/node_modules/*
+data/*/*
+
+**/*.map
+cookies.txt
+uploads/*
+
+user_files/*
+template_files/*
+
+**.swp
+
+/log.json
+hash_folder
+
+# managed by dev-environment$ bin/update_build_scripts
+.npmrc

services/filestore/.nvmrc

@@ -0,0 +1 @@
+12.22.3

services/filestore/.prettierignore

@@ -0,0 +1 @@
+node_modules

services/filestore/.prettierrc

@@ -0,0 +1,11 @@
+# This file was auto-generated, do not edit it directly.
+# Instead run bin/update_build_scripts from
+# https://github.com/sharelatex/sharelatex-dev-environment
+{
+  "arrowParens": "avoid",
+  "semi": false,
+  "singleQuote": true,
+  "trailingComma": "es5",
+  "tabWidth": 2,
+  "useTabs": false
+}

services/filestore/Dockerfile

@@ -0,0 +1,27 @@
+# This file was auto-generated, do not edit it directly.
+# Instead run bin/update_build_scripts from
+# https://github.com/sharelatex/sharelatex-dev-environment
+
+FROM node:12.22.3 as base
+
+WORKDIR /app
+COPY install_deps.sh /app
+RUN chmod 0755 ./install_deps.sh && ./install_deps.sh
+
+FROM base as app
+
+#wildcard as some files may not be in all repos
+COPY package*.json npm-shrink*.json /app/
+
+RUN npm ci --quiet
+
+COPY . /app
+
+FROM base
+
+COPY --from=app /app /app
+RUN mkdir -p uploads user_files template_files \
+&&  chown node:node uploads user_files template_files
+USER node
+
+CMD ["node", "--expose-gc", "app.js"]

services/filestore/LICENSE

@@ -0,0 +1,662 @@
+
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  Developers that use our General Public Licenses protect your rights
+with two steps: (1) assert copyright on the software, and (2) offer
+you this License which gives you legal permission to copy, distribute
+and/or modify the software.
+
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+improvements made in alternate versions of the program, if they
+receive widespread use, become available for other developers to
+incorporate.  Many developers of free software are heartened and
+encouraged by the resulting cooperation.  However, in the case of
+software used on network servers, this result may fail to come about.
+The GNU General Public License permits making a modified version and
+letting the public access it on a server without ever releasing its
+source code to the public.
+
+  The GNU Affero General Public License is designed specifically to
+ensure that, in such cases, the modified source code becomes available
+to the community.  It requires the operator of a network server to
+provide the source code of the modified version running there to the
+users of that server.  Therefore, public use of a modified version, on
+a publicly accessible server, gives the public access to the source
+code of the modified version.
+
+  An older license, called the Affero General Public License and
+published by Affero, was designed to accomplish similar goals.  This is
+a different license, not a version of the Affero GPL, but Affero has
+released a new version of the Affero GPL which permits relicensing under
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+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
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+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Remote Network Interaction; Use with the GNU General Public License.
+
+  Notwithstanding any other provision of this License, if you modify the
+Program, your modified version must prominently offer all users
+interacting with it remotely through a computer network (if your version
+supports such interaction) an opportunity to receive the Corresponding
+Source of your version by providing access to the Corresponding Source
+from a network server at no charge, through some standard or customary
+means of facilitating copying of software.  This Corresponding Source
+shall include the Corresponding Source for any work covered by version 3
+of the GNU General Public License that is incorporated pursuant to the
+following paragraph.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the work with which it is combined will remain governed by version
+3 of the GNU General Public License.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU Affero General Public License from time to time.  Such new versions
+will be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU Affero General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU Affero General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU Affero General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.

services/filestore/Makefile

@@ -0,0 +1,90 @@
+# This file was auto-generated, do not edit it directly.
+# Instead run bin/update_build_scripts from
+# https://github.com/sharelatex/sharelatex-dev-environment
+
+BUILD_NUMBER ?= local
+BRANCH_NAME ?= $(shell git rev-parse --abbrev-ref HEAD)
+PROJECT_NAME = filestore
+BUILD_DIR_NAME = $(shell pwd | xargs basename | tr -cd '[a-zA-Z0-9_.\-]')
+
+DOCKER_COMPOSE_FLAGS ?= -f docker-compose.yml
+DOCKER_COMPOSE := BUILD_NUMBER=$(BUILD_NUMBER) \
+	BRANCH_NAME=$(BRANCH_NAME) \
+	PROJECT_NAME=$(PROJECT_NAME) \
+	MOCHA_GREP=${MOCHA_GREP} \
+	docker-compose ${DOCKER_COMPOSE_FLAGS}
+
+DOCKER_COMPOSE_TEST_ACCEPTANCE = \
+	COMPOSE_PROJECT_NAME=test_acceptance_$(BUILD_DIR_NAME) $(DOCKER_COMPOSE)
+
+DOCKER_COMPOSE_TEST_UNIT = \
+	COMPOSE_PROJECT_NAME=test_unit_$(BUILD_DIR_NAME) $(DOCKER_COMPOSE)
+
+clean:
+	-docker rmi ci/$(PROJECT_NAME):$(BRANCH_NAME)-$(BUILD_NUMBER)
+	-docker rmi gcr.io/overleaf-ops/$(PROJECT_NAME):$(BRANCH_NAME)-$(BUILD_NUMBER)
+	-$(DOCKER_COMPOSE_TEST_UNIT) down --rmi local
+	-$(DOCKER_COMPOSE_TEST_ACCEPTANCE) down --rmi local
+
+format:
+	$(DOCKER_COMPOSE) run --rm test_unit npm run --silent format
+
+format_fix:
+	$(DOCKER_COMPOSE) run --rm test_unit npm run --silent format:fix
+
+lint:
+	$(DOCKER_COMPOSE) run --rm test_unit npm run --silent lint
+
+test: format lint test_unit test_acceptance
+
+test_unit:
+ifneq (,$(wildcard test/unit))
+	$(DOCKER_COMPOSE_TEST_UNIT) run --rm test_unit
+	$(MAKE) test_unit_clean
+endif
+
+test_clean: test_unit_clean
+test_unit_clean:
+ifneq (,$(wildcard test/unit))
+	$(DOCKER_COMPOSE_TEST_UNIT) down -v -t 0
+endif
+
+test_acceptance: test_acceptance_clean test_acceptance_pre_run test_acceptance_run
+	$(MAKE) test_acceptance_clean
+
+test_acceptance_debug: test_acceptance_clean test_acceptance_pre_run test_acceptance_run_debug
+	$(MAKE) test_acceptance_clean
+
+test_acceptance_run:
+ifneq (,$(wildcard test/acceptance))
+	$(DOCKER_COMPOSE_TEST_ACCEPTANCE) run --rm test_acceptance
+endif
+
+test_acceptance_run_debug:
+ifneq (,$(wildcard test/acceptance))
+	$(DOCKER_COMPOSE_TEST_ACCEPTANCE) run -p 127.0.0.9:19999:19999 --rm test_acceptance npm run test:acceptance -- --inspect=0.0.0.0:19999 --inspect-brk
+endif
+
+test_clean: test_acceptance_clean
+test_acceptance_clean:
+	$(DOCKER_COMPOSE_TEST_ACCEPTANCE) down -v -t 0
+
+test_acceptance_pre_run:
+ifneq (,$(wildcard test/acceptance/js/scripts/pre-run))
+	$(DOCKER_COMPOSE_TEST_ACCEPTANCE) run --rm test_acceptance test/acceptance/js/scripts/pre-run
+endif
+
+build:
+	docker build --pull --tag ci/$(PROJECT_NAME):$(BRANCH_NAME)-$(BUILD_NUMBER) \
+		--tag gcr.io/overleaf-ops/$(PROJECT_NAME):$(BRANCH_NAME)-$(BUILD_NUMBER) \
+		.
+
+tar:
+	$(DOCKER_COMPOSE) up tar
+
+publish:
+
+	docker push $(DOCKER_REPO)/$(PROJECT_NAME):$(BRANCH_NAME)-$(BUILD_NUMBER)
+
+
+.PHONY: clean test test_unit test_acceptance test_clean build publish

services/filestore/README.md

@@ -0,0 +1,22 @@
+overleaf/filestore
+====================
+
+An API for CRUD operations on binary files stored in S3
+
+filestore acts as a proxy between the CLSIs and (currently) Amazon S3 storage, presenting a RESTful HTTP interface to the CLSIs on port 3009 by default. Urls are mapped to node functions in https://github.com/overleaf/filestore/blob/master/app.coffee . URLs are of the form:
+
+* `/project/:project_id/file/:file_id`
+* `/template/:template_id/v/:version/:format`
+* `/project/:project_id/public/:public_file_id`
+* `/project/:project_id/size`
+* `/bucket/:bucket/key/*`
+* `/shutdown`
+* `/status` - returns `filestore sharelatex up` or `server is being shut down` (HTTP 500)
+* `/health_check` 
+
+License
+-------
+
+The code in this repository is released under the GNU AFFERO GENERAL PUBLIC LICENSE, version 3. A copy can be found in the `LICENSE` file.
+
+Copyright (c) Overleaf, 2014-2019.

services/filestore/app.js

@@ -0,0 +1,161 @@
+const Metrics = require('@overleaf/metrics')
+Metrics.initialize(process.env.METRICS_APP_NAME || 'filestore')
+
+const logger = require('logger-sharelatex')
+logger.initialize(process.env.METRICS_APP_NAME || 'filestore')
+
+const settings = require('@overleaf/settings')
+const express = require('express')
+const bodyParser = require('body-parser')
+
+const fileController = require('./app/js/FileController')
+const keyBuilder = require('./app/js/KeyBuilder')
+const healthCheckController = require('./app/js/HealthCheckController')
+
+const RequestLogger = require('./app/js/RequestLogger')
+
+const app = express()
+
+app.use(RequestLogger.middleware)
+
+if (settings.sentry && settings.sentry.dsn) {
+  logger.initializeErrorReporting(settings.sentry.dsn)
+}
+
+Metrics.open_sockets.monitor(logger)
+Metrics.memory.monitor(logger)
+if (Metrics.event_loop) {
+  Metrics.event_loop.monitor(logger)
+}
+
+app.use(function (req, res, next) {
+  Metrics.inc('http-request')
+  next()
+})
+
+Metrics.injectMetricsRoute(app)
+
+app.head(
+  '/project/:project_id/file/:file_id',
+  keyBuilder.userFileKeyMiddleware,
+  fileController.getFileHead
+)
+app.get(
+  '/project/:project_id/file/:file_id',
+  keyBuilder.userFileKeyMiddleware,
+  fileController.getFile
+)
+app.post(
+  '/project/:project_id/file/:file_id',
+  keyBuilder.userFileKeyMiddleware,
+  fileController.insertFile
+)
+app.put(
+  '/project/:project_id/file/:file_id',
+  keyBuilder.userFileKeyMiddleware,
+  bodyParser.json(),
+  fileController.copyFile
+)
+app.delete(
+  '/project/:project_id/file/:file_id',
+  keyBuilder.userFileKeyMiddleware,
+  fileController.deleteFile
+)
+app.delete(
+  '/project/:project_id',
+  keyBuilder.userProjectKeyMiddleware,
+  fileController.deleteProject
+)
+
+app.head(
+  '/template/:template_id/v/:version/:format',
+  keyBuilder.templateFileKeyMiddleware,
+  fileController.getFileHead
+)
+app.get(
+  '/template/:template_id/v/:version/:format',
+  keyBuilder.templateFileKeyMiddleware,
+  fileController.getFile
+)
+app.get(
+  '/template/:template_id/v/:version/:format/:sub_type',
+  keyBuilder.templateFileKeyMiddleware,
+  fileController.getFile
+)
+app.post(
+  '/template/:template_id/v/:version/:format',
+  keyBuilder.templateFileKeyMiddleware,
+  fileController.insertFile
+)
+
+app.head(
+  '/project/:project_id/public/:public_file_id',
+  keyBuilder.publicFileKeyMiddleware,
+  fileController.getFileHead
+)
+app.get(
+  '/project/:project_id/public/:public_file_id',
+  keyBuilder.publicFileKeyMiddleware,
+  fileController.getFile
+)
+app.post(
+  '/project/:project_id/public/:public_file_id',
+  keyBuilder.publicFileKeyMiddleware,
+  fileController.insertFile
+)
+app.put(
+  '/project/:project_id/public/:public_file_id',
+  keyBuilder.publicFileKeyMiddleware,
+  bodyParser.json(),
+  fileController.copyFile
+)
+app.delete(
+  '/project/:project_id/public/:public_file_id',
+  keyBuilder.publicFileKeyMiddleware,
+  fileController.deleteFile
+)
+
+app.get(
+  '/project/:project_id/size',
+  keyBuilder.publicProjectKeyMiddleware,
+  fileController.directorySize
+)
+
+app.get(
+  '/bucket/:bucket/key/*',
+  keyBuilder.bucketFileKeyMiddleware,
+  fileController.getFile
+)
+
+app.get('/status', function (req, res) {
+  res.send('filestore sharelatex up')
+})
+
+app.get('/health_check', healthCheckController.check)
+
+app.use(RequestLogger.errorHandler)
+
+const port = settings.internal.filestore.port || 3009
+const host = '0.0.0.0'
+
+if (!module.parent) {
+  // Called directly
+  app.listen(port, host, error => {
+    if (error) {
+      logger.error('Error starting Filestore', error)
+      throw error
+    }
+    logger.info(`Filestore starting up, listening on ${host}:${port}`)
+  })
+}
+
+process
+  .on('unhandledRejection', (reason, p) => {
+    logger.err(reason, 'Unhandled Rejection at Promise', p)
+  })
+  .on('uncaughtException', err => {
+    logger.err(err, 'Uncaught Exception thrown')
+    process.exit(1)
+  })
+
+module.exports = app

services/filestore/app/js/Errors.js

@@ -0,0 +1,30 @@
+const OError = require('@overleaf/o-error')
+const { Errors } = require('@overleaf/object-persistor')
+
+class HealthCheckError extends OError {}
+class ConversionsDisabledError extends OError {}
+class ConversionError extends OError {}
+class TimeoutError extends OError {}
+class InvalidParametersError extends OError {}
+
+class FailedCommandError extends OError {
+  constructor(command, code, stdout, stderr) {
+    super('command failed with error exit code', {
+      command,
+      code,
+    })
+    this.stdout = stdout
+    this.stderr = stderr
+    this.code = code
+  }
+}
+
+module.exports = {
+  FailedCommandError,
+  ConversionsDisabledError,
+  ConversionError,
+  HealthCheckError,
+  TimeoutError,
+  InvalidParametersError,
+  ...Errors,
+}

services/filestore/app/js/FileController.js

@@ -0,0 +1,214 @@
+const PersistorManager = require('./PersistorManager')
+const FileHandler = require('./FileHandler')
+const metrics = require('@overleaf/metrics')
+const parseRange = require('range-parser')
+const Errors = require('./Errors')
+const { pipeline } = require('stream')
+
+const maxSizeInBytes = 1024 * 1024 * 1024 // 1GB
+
+module.exports = {
+  getFile,
+  getFileHead,
+  insertFile,
+  copyFile,
+  deleteFile,
+  deleteProject,
+  directorySize,
+}
+
+function getFile(req, res, next) {
+  const { key, bucket } = req
+  const { format, style } = req.query
+  const options = {
+    key,
+    bucket,
+    format,
+    style,
+  }
+
+  metrics.inc('getFile')
+  req.requestLogger.setMessage('getting file')
+  req.requestLogger.addFields({
+    key,
+    bucket,
+    format,
+    style,
+    cacheWarm: req.query.cacheWarm,
+  })
+
+  if (req.headers.range) {
+    const range = _getRange(req.headers.range)
+    if (range) {
+      options.start = range.start
+      options.end = range.end
+      req.requestLogger.addFields({ range })
+    }
+  }
+
+  FileHandler.getRedirectUrl(bucket, key, options, function (err, redirectUrl) {
+    if (err) {
+      metrics.inc('file_redirect_error')
+    }
+
+    if (redirectUrl) {
+      metrics.inc('file_redirect')
+      return res.redirect(redirectUrl)
+    }
+
+    FileHandler.getFile(bucket, key, options, function (err, fileStream) {
+      if (err) {
+        if (err instanceof Errors.NotFoundError) {
+          res.sendStatus(404)
+        } else {
+          next(err)
+        }
+        return
+      }
+
+      if (req.query.cacheWarm) {
+        return res.sendStatus(200).end()
+      }
+
+      pipeline(fileStream, res, err => {
+        if (err && err.code === 'ERR_STREAM_PREMATURE_CLOSE') {
+          res.end()
+        } else if (err) {
+          next(
+            new Errors.ReadError(
+              'error transferring stream',
+              { bucket, key, format, style },
+              err
+            )
+          )
+        }
+      })
+    })
+  })
+}
+
+function getFileHead(req, res, next) {
+  const { key, bucket } = req
+
+  metrics.inc('getFileSize')
+  req.requestLogger.setMessage('getting file size')
+  req.requestLogger.addFields({ key, bucket })
+
+  FileHandler.getFileSize(bucket, key, function (err, fileSize) {
+    if (err) {
+      if (err instanceof Errors.NotFoundError) {
+        res.sendStatus(404)
+      } else {
+        next(err)
+      }
+      return
+    }
+    res.set('Content-Length', fileSize)
+    res.status(200).end()
+  })
+}
+
+function insertFile(req, res, next) {
+  metrics.inc('insertFile')
+  const { key, bucket } = req
+
+  req.requestLogger.setMessage('inserting file')
+  req.requestLogger.addFields({ key, bucket })
+
+  FileHandler.insertFile(bucket, key, req, function (err) {
+    if (err) {
+      next(err)
+    } else {
+      res.sendStatus(200)
+    }
+  })
+}
+
+function copyFile(req, res, next) {
+  metrics.inc('copyFile')
+  const { key, bucket } = req
+  const oldProjectId = req.body.source.project_id
+  const oldFileId = req.body.source.file_id
+
+  req.requestLogger.addFields({
+    key,
+    bucket,
+    oldProject_id: oldProjectId,
+    oldFile_id: oldFileId,
+  })
+  req.requestLogger.setMessage('copying file')
+
+  PersistorManager.copyObject(bucket, `${oldProjectId}/${oldFileId}`, key)
+    .then(() => res.sendStatus(200))
+    .catch(err => {
+      if (err) {
+        if (err instanceof Errors.NotFoundError) {
+          res.sendStatus(404)
+        } else {
+          next(err)
+        }
+      }
+    })
+}
+
+function deleteFile(req, res, next) {
+  metrics.inc('deleteFile')
+  const { key, bucket } = req
+
+  req.requestLogger.addFields({ key, bucket })
+  req.requestLogger.setMessage('deleting file')
+
+  FileHandler.deleteFile(bucket, key, function (err) {
+    if (err) {
+      next(err)
+    } else {
+      res.sendStatus(204)
+    }
+  })
+}
+
+function deleteProject(req, res, next) {
+  metrics.inc('deleteProject')
+  const { key, bucket } = req
+
+  req.requestLogger.setMessage('deleting project')
+  req.requestLogger.addFields({ key, bucket })
+
+  FileHandler.deleteProject(bucket, key, function (err) {
+    if (err) {
+      if (err instanceof Errors.InvalidParametersError) {
+        return res.sendStatus(400)
+      }
+      next(err)
+    } else {
+      res.sendStatus(204)
+    }
+  })
+}
+
+function directorySize(req, res, next) {
+  metrics.inc('projectSize')
+  const { project_id: projectId, bucket } = req
+
+  req.requestLogger.setMessage('getting project size')
+  req.requestLogger.addFields({ projectId, bucket })
+
+  FileHandler.getDirectorySize(bucket, projectId, function (err, size) {
+    if (err) {
+      return next(err)
+    }
+
+    res.json({ 'total bytes': size })
+    req.requestLogger.addFields({ size })
+  })
+}
+
+function _getRange(header) {
+  const parsed = parseRange(maxSizeInBytes, header)
+  if (parsed === -1 || parsed === -2 || parsed.type !== 'bytes') {
+    return null
+  } else {
+    const range = parsed[0]
+    return { start: range.start, end: range.end }
+  }
+}

services/filestore/app/js/FileConverter.js

@@ -0,0 +1,98 @@
+const metrics = require('@overleaf/metrics')
+const Settings = require('@overleaf/settings')
+const { callbackify } = require('util')
+
+const safeExec = require('./SafeExec').promises
+const { ConversionError } = require('./Errors')
+
+const APPROVED_FORMATS = ['png']
+const FOURTY_SECONDS = 40 * 1000
+const KILL_SIGNAL = 'SIGTERM'
+
+module.exports = {
+  convert: callbackify(convert),
+  thumbnail: callbackify(thumbnail),
+  preview: callbackify(preview),
+  promises: {
+    convert,
+    thumbnail,
+    preview,
+  },
+}
+
+async function convert(sourcePath, requestedFormat) {
+  const width = '600x'
+  return _convert(sourcePath, requestedFormat, [
+    'convert',
+    '-define',
+    `pdf:fit-page=${width}`,
+    '-flatten',
+    '-density',
+    '300',
+    `${sourcePath}[0]`,
+  ])
+}
+
+async function thumbnail(sourcePath) {
+  const width = '260x'
+  return convert(sourcePath, 'png', [
+    'convert',
+    '-flatten',
+    '-background',
+    'white',
+    '-density',
+    '300',
+    '-define',
+    `pdf:fit-page=${width}`,
+    `${sourcePath}[0]`,
+    '-resize',
+    width,
+  ])
+}
+
+async function preview(sourcePath) {
+  const width = '548x'
+  return convert(sourcePath, 'png', [
+    'convert',
+    '-flatten',
+    '-background',
+    'white',
+    '-density',
+    '300',
+    '-define',
+    `pdf:fit-page=${width}`,
+    `${sourcePath}[0]`,
+    '-resize',
+    width,
+  ])
+}
+
+async function _convert(sourcePath, requestedFormat, command) {
+  if (!APPROVED_FORMATS.includes(requestedFormat)) {
+    throw new ConversionError('invalid format requested', {
+      format: requestedFormat,
+    })
+  }
+
+  const timer = new metrics.Timer('imageConvert')
+  const destPath = `${sourcePath}.${requestedFormat}`
+
+  command.push(destPath)
+  command = Settings.commands.convertCommandPrefix.concat(command)
+
+  try {
+    await safeExec(command, {
+      killSignal: KILL_SIGNAL,
+      timeout: FOURTY_SECONDS,
+    })
+  } catch (err) {
+    throw new ConversionError(
+      'something went wrong converting file',
+      { stderr: err.stderr, sourcePath, requestedFormat, destPath },
+      err
+    )
+  }
+
+  timer.done()
+  return destPath
+}

services/filestore/app/js/FileHandler.js

@@ -0,0 +1,195 @@
+const Settings = require('@overleaf/settings')
+const { callbackify } = require('util')
+const fs = require('fs')
+const PersistorManager = require('./PersistorManager')
+const LocalFileWriter = require('./LocalFileWriter')
+const FileConverter = require('./FileConverter')
+const KeyBuilder = require('./KeyBuilder')
+const ImageOptimiser = require('./ImageOptimiser')
+const { ConversionError, InvalidParametersError } = require('./Errors')
+
+module.exports = {
+  insertFile: callbackify(insertFile),
+  deleteFile: callbackify(deleteFile),
+  deleteProject: callbackify(deleteProject),
+  getFile: callbackify(getFile),
+  getRedirectUrl: callbackify(getRedirectUrl),
+  getFileSize: callbackify(getFileSize),
+  getDirectorySize: callbackify(getDirectorySize),
+  promises: {
+    getFile,
+    getRedirectUrl,
+    insertFile,
+    deleteFile,
+    deleteProject,
+    getFileSize,
+    getDirectorySize,
+  },
+}
+
+async function insertFile(bucket, key, stream) {
+  const convertedKey = KeyBuilder.getConvertedFolderKey(key)
+  if (!convertedKey.match(/^[0-9a-f]{24}\/([0-9a-f]{24}|v\/[0-9]+\/[a-z]+)/i)) {
+    throw new InvalidParametersError('key does not match validation regex', {
+      bucket,
+      key,
+      convertedKey,
+    })
+  }
+  if (Settings.enableConversions) {
+    await PersistorManager.deleteDirectory(bucket, convertedKey)
+  }
+  await PersistorManager.sendStream(bucket, key, stream)
+}
+
+async function deleteFile(bucket, key) {
+  const convertedKey = KeyBuilder.getConvertedFolderKey(key)
+  if (!convertedKey.match(/^[0-9a-f]{24}\/([0-9a-f]{24}|v\/[0-9]+\/[a-z]+)/i)) {
+    throw new InvalidParametersError('key does not match validation regex', {
+      bucket,
+      key,
+      convertedKey,
+    })
+  }
+  const jobs = [PersistorManager.deleteObject(bucket, key)]
+  if (Settings.enableConversions) {
+    jobs.push(PersistorManager.deleteDirectory(bucket, convertedKey))
+  }
+  await Promise.all(jobs)
+}
+
+async function deleteProject(bucket, key) {
+  if (!key.match(/^[0-9a-f]{24}\//i)) {
+    throw new InvalidParametersError('key does not match validation regex', {
+      bucket,
+      key,
+    })
+  }
+  await PersistorManager.deleteDirectory(bucket, key)
+}
+
+async function getFile(bucket, key, opts) {
+  opts = opts || {}
+  if (!opts.format && !opts.style) {
+    return PersistorManager.getObjectStream(bucket, key, opts)
+  } else {
+    return _getConvertedFile(bucket, key, opts)
+  }
+}
+
+async function getRedirectUrl(bucket, key, opts) {
+  // if we're doing anything unusual with options, or the request isn't for
+  // one of the default buckets, return null so that we proxy the file
+  opts = opts || {}
+  if (
+    !opts.start &&
+    !opts.end &&
+    !opts.format &&
+    !opts.style &&
+    Object.values(Settings.filestore.stores).includes(bucket) &&
+    Settings.filestore.allowRedirects
+  ) {
+    return PersistorManager.getRedirectUrl(bucket, key)
+  }
+
+  return null
+}
+
+async function getFileSize(bucket, key) {
+  return PersistorManager.getObjectSize(bucket, key)
+}
+
+async function getDirectorySize(bucket, projectId) {
+  return PersistorManager.directorySize(bucket, projectId)
+}
+
+async function _getConvertedFile(bucket, key, opts) {
+  const convertedKey = KeyBuilder.addCachingToKey(key, opts)
+  const exists = await PersistorManager.checkIfObjectExists(
+    bucket,
+    convertedKey
+  )
+  if (exists) {
+    return PersistorManager.getObjectStream(bucket, convertedKey, opts)
+  } else {
+    return _getConvertedFileAndCache(bucket, key, convertedKey, opts)
+  }
+}
+
+async function _getConvertedFileAndCache(bucket, key, convertedKey, opts) {
+  let convertedFsPath
+  try {
+    convertedFsPath = await _convertFile(bucket, key, opts)
+    await ImageOptimiser.promises.compressPng(convertedFsPath)
+    await PersistorManager.sendFile(bucket, convertedKey, convertedFsPath)
+  } catch (err) {
+    LocalFileWriter.deleteFile(convertedFsPath, () => {})
+    throw new ConversionError(
+      'failed to convert file',
+      { opts, bucket, key, convertedKey },
+      err
+    )
+  }
+  // Send back the converted file from the local copy to avoid problems
+  // with the file not being present in S3 yet.  As described in the
+  // documentation below, we have already made a 'HEAD' request in
+  // checkIfFileExists so we only have "eventual consistency" if we try
+  // to stream it from S3 here.  This was a cause of many 403 errors.
+  //
+  // "Amazon S3 provides read-after-write consistency for PUTS of new
+  // objects in your S3 bucket in all regions with one caveat. The
+  // caveat is that if you make a HEAD or GET request to the key name
+  // (to find if the object exists) before creating the object, Amazon
+  // S3 provides eventual consistency for read-after-write.""
+  // https://docs.aws.amazon.com/AmazonS3/latest/dev/Introduction.html#ConsistencyModel
+  const readStream = fs.createReadStream(convertedFsPath)
+  readStream.on('end', function () {
+    LocalFileWriter.deleteFile(convertedFsPath, function () {})
+  })
+  return readStream
+}
+
+async function _convertFile(bucket, originalKey, opts) {
+  let originalFsPath
+  try {
+    originalFsPath = await _writeFileToDisk(bucket, originalKey, opts)
+  } catch (err) {
+    throw new ConversionError(
+      'unable to write file to disk',
+      { bucket, originalKey, opts },
+      err
+    )
+  }
+
+  let promise
+  if (opts.format) {
+    promise = FileConverter.promises.convert(originalFsPath, opts.format)
+  } else if (opts.style === 'thumbnail') {
+    promise = FileConverter.promises.thumbnail(originalFsPath)
+  } else if (opts.style === 'preview') {
+    promise = FileConverter.promises.preview(originalFsPath)
+  } else {
+    throw new ConversionError('invalid file conversion options', {
+      bucket,
+      originalKey,
+      opts,
+    })
+  }
+  let destPath
+  try {
+    destPath = await promise
+  } catch (err) {
+    throw new ConversionError(
+      'error converting file',
+      { bucket, originalKey, opts },
+      err
+    )
+  }
+  LocalFileWriter.deleteFile(originalFsPath, function () {})
+  return destPath
+}
+
+async function _writeFileToDisk(bucket, key, opts) {
+  const fileStream = await PersistorManager.getObjectStream(bucket, key, opts)
+  return LocalFileWriter.promises.writeStream(fileStream, key)
+}

services/filestore/app/js/HealthCheckController.js

@@ -0,0 +1,69 @@
+const fs = require('fs')
+const path = require('path')
+const Settings = require('@overleaf/settings')
+const streamBuffers = require('stream-buffers')
+const { promisify } = require('util')
+const Stream = require('stream')
+
+const pipeline = promisify(Stream.pipeline)
+const fsCopy = promisify(fs.copyFile)
+const fsUnlink = promisify(fs.unlink)
+
+const { HealthCheckError } = require('./Errors')
+const FileConverter = require('./FileConverter').promises
+const FileHandler = require('./FileHandler').promises
+
+async function checkCanGetFiles() {
+  if (!Settings.health_check) {
+    return
+  }
+
+  const projectId = Settings.health_check.project_id
+  const fileId = Settings.health_check.file_id
+  const key = `${projectId}/${fileId}`
+  const bucket = Settings.filestore.stores.user_files
+
+  const buffer = new streamBuffers.WritableStreamBuffer({
+    initialSize: 100,
+  })
+
+  const sourceStream = await FileHandler.getFile(bucket, key, {})
+  try {
+    await pipeline(sourceStream, buffer)
+  } catch (err) {
+    throw new HealthCheckError('failed to get health-check file', {}, err)
+  }
+
+  if (!buffer.size()) {
+    throw new HealthCheckError('no bytes written to download stream')
+  }
+}
+
+async function checkFileConvert() {
+  if (!Settings.enableConversions) {
+    return
+  }
+
+  const imgPath = path.join(Settings.path.uploadFolder, '/tiny.pdf')
+
+  let resultPath
+  try {
+    await fsCopy('./tiny.pdf', imgPath)
+    resultPath = await FileConverter.thumbnail(imgPath)
+  } finally {
+    if (resultPath) {
+      await fsUnlink(resultPath)
+    }
+    await fsUnlink(imgPath)
+  }
+}
+
+module.exports = {
+  check(req, res, next) {
+    Promise.all([checkCanGetFiles(), checkFileConvert()])
+      .then(() => res.sendStatus(200))
+      .catch(err => {
+        next(err)
+      })
+  },
+}

services/filestore/app/js/ImageOptimiser.js

@@ -0,0 +1,34 @@
+const logger = require('logger-sharelatex')
+const metrics = require('@overleaf/metrics')
+const { callbackify } = require('util')
+const safeExec = require('./SafeExec').promises
+
+module.exports = {
+  compressPng: callbackify(compressPng),
+  promises: {
+    compressPng,
+  },
+}
+
+async function compressPng(localPath, callback) {
+  const timer = new metrics.Timer('compressPng')
+  const args = ['optipng', localPath]
+  const opts = {
+    timeout: 30 * 1000,
+    killSignal: 'SIGKILL',
+  }
+
+  try {
+    await safeExec(args, opts)
+    timer.done()
+  } catch (err) {
+    if (err.code === 'SIGKILL') {
+      logger.warn(
+        { err, stderr: err.stderr, localPath },
+        'optimiser timeout reached'
+      )
+    } else {
+      throw err
+    }
+  }
+}

services/filestore/app/js/KeyBuilder.js

@@ -0,0 +1,93 @@
+const settings = require('@overleaf/settings')
+
+module.exports = {
+  getConvertedFolderKey,
+  addCachingToKey,
+  userFileKeyMiddleware,
+  userProjectKeyMiddleware,
+  publicFileKeyMiddleware,
+  publicProjectKeyMiddleware,
+  bucketFileKeyMiddleware,
+  templateFileKeyMiddleware,
+}
+
+function getConvertedFolderKey(key) {
+  return `${key}-converted-cache/`
+}
+
+function addCachingToKey(key, opts) {
+  key = this.getConvertedFolderKey(key)
+
+  if (opts.format && !opts.style) {
+    key = `${key}format-${opts.format}`
+  }
+  if (opts.style && !opts.format) {
+    key = `${key}style-${opts.style}`
+  }
+  if (opts.style && opts.format) {
+    key = `${key}format-${opts.format}-style-${opts.style}`
+  }
+
+  return key
+}
+
+function userFileKeyMiddleware(req, res, next) {
+  const { project_id: projectId, file_id: fileId } = req.params
+  req.key = `${projectId}/${fileId}`
+  req.bucket = settings.filestore.stores.user_files
+  next()
+}
+
+function userProjectKeyMiddleware(req, res, next) {
+  const { project_id: projectId } = req.params
+  req.key = `${projectId}/`
+  req.bucket = settings.filestore.stores.user_files
+  next()
+}
+
+function publicFileKeyMiddleware(req, res, next) {
+  if (settings.filestore.stores.public_files == null) {
+    return res.status(501).send('public files not available')
+  }
+
+  const { project_id: projectId, public_file_id: publicFileId } = req.params
+  req.key = `${projectId}/${publicFileId}`
+  req.bucket = settings.filestore.stores.public_files
+
+  next()
+}
+
+function bucketFileKeyMiddleware(req, res, next) {
+  req.bucket = req.params.bucket
+  req.key = req.params[0]
+  next()
+}
+
+function templateFileKeyMiddleware(req, res, next) {
+  const {
+    template_id: templateId,
+    format,
+    version,
+    sub_type: subType,
+  } = req.params
+
+  req.key = `${templateId}/v/${version}/${format}`
+
+  if (subType) {
+    req.key = `${req.key}/${subType}`
+  }
+
+  req.bucket = settings.filestore.stores.template_files
+  req.version = version
+
+  next()
+}
+
+function publicProjectKeyMiddleware(req, res, next) {
+  const { project_id: projectId } = req.params
+
+  req.project_id = projectId
+  req.bucket = settings.filestore.stores.user_files
+
+  next()
+}

services/filestore/app/js/LocalFileWriter.js

@@ -0,0 +1,56 @@
+const fs = require('fs')
+const uuid = require('node-uuid')
+const path = require('path')
+const Stream = require('stream')
+const { callbackify, promisify } = require('util')
+const metrics = require('@overleaf/metrics')
+const Settings = require('@overleaf/settings')
+const { WriteError } = require('./Errors')
+
+module.exports = {
+  promises: {
+    writeStream,
+    deleteFile,
+  },
+  writeStream: callbackify(writeStream),
+  deleteFile: callbackify(deleteFile),
+}
+
+const pipeline = promisify(Stream.pipeline)
+
+async function writeStream(stream, key) {
+  const timer = new metrics.Timer('writingFile')
+  const fsPath = _getPath(key)
+
+  const writeStream = fs.createWriteStream(fsPath)
+  try {
+    await pipeline(stream, writeStream)
+    timer.done()
+    return fsPath
+  } catch (err) {
+    await deleteFile(fsPath)
+
+    throw new WriteError('problem writing file locally', { fsPath }, err)
+  }
+}
+
+async function deleteFile(fsPath) {
+  if (!fsPath) {
+    return
+  }
+  try {
+    await promisify(fs.unlink)(fsPath)
+  } catch (err) {
+    if (err.code !== 'ENOENT') {
+      throw new WriteError('failed to delete file', { fsPath }, err)
+    }
+  }
+}
+
+function _getPath(key) {
+  if (key == null) {
+    key = uuid.v1()
+  }
+  key = key.replace(/\//g, '-')
+  return path.join(Settings.path.uploadFolder, key)
+}

services/filestore/app/js/PersistorManager.js

@@ -0,0 +1,10 @@
+const settings = require('@overleaf/settings')
+
+const persistorSettings = settings.filestore
+persistorSettings.Metrics = require('@overleaf/metrics')
+persistorSettings.paths = settings.path
+
+const ObjectPersistor = require('@overleaf/object-persistor')
+const persistor = ObjectPersistor(persistorSettings)
+
+module.exports = persistor

services/filestore/app/js/RequestLogger.js

@@ -0,0 +1,77 @@
+const logger = require('logger-sharelatex')
+const metrics = require('@overleaf/metrics')
+
+class RequestLogger {
+  constructor() {
+    this._logInfo = {}
+    this._logMessage = 'http request'
+  }
+
+  addFields(fields) {
+    Object.assign(this._logInfo, fields)
+  }
+
+  setMessage(message) {
+    this._logMessage = message
+  }
+
+  static errorHandler(err, req, res, next) {
+    req.requestLogger.addFields({ error: err })
+    res.status(500).send(err.message)
+  }
+
+  static middleware(req, res, next) {
+    const startTime = new Date()
+    req.requestLogger = new RequestLogger()
+
+    // override the 'end' method to log and record metrics
+    const end = res.end
+    res.end = function () {
+      // apply the standard request 'end' method before logging and metrics
+      end.apply(this, arguments)
+
+      const responseTime = new Date() - startTime
+
+      const routePath = req.route && req.route.path.toString()
+
+      if (routePath) {
+        metrics.timing('http_request', responseTime, null, {
+          method: req.method,
+          status_code: res.statusCode,
+          path: routePath.replace(/\//g, '_').replace(/:/g, '').slice(1),
+        })
+      }
+
+      const level = res.statusCode >= 500 ? 'err' : 'log'
+      logger[level](
+        {
+          req: {
+            url: req.originalUrl || req.url,
+            route: routePath,
+            method: req.method,
+            referrer: req.headers.referer || req.headers.referrer,
+            'remote-addr':
+              req.ip ||
+              (req.socket && req.socket.remoteAddress) ||
+              (req.socket &&
+                req.socket.socket &&
+                req.socket.socket.remoteAddress),
+            'user-agent': req.headers['user-agent'],
+            'content-length': req.headers['content-length'],
+          },
+          res: {
+            'content-length': res._headers['content-length'],
+            statusCode: res.statusCode,
+            'response-time': responseTime,
+          },
+          info: req.requestLogger._logInfo,
+        },
+        req.requestLogger._logMessage
+      )
+    }
+
+    next()
+  }
+}
+
+module.exports = RequestLogger

services/filestore/app/js/SafeExec.js

@@ -0,0 +1,85 @@
+const lodashOnce = require('lodash.once')
+const childProcess = require('child_process')
+const Settings = require('@overleaf/settings')
+const { ConversionsDisabledError, FailedCommandError } = require('./Errors')
+
+// execute a command in the same way as 'exec' but with a timeout that
+// kills all child processes
+//
+// we spawn the command with 'detached:true' to make a new process
+// group, then we can kill everything in that process group.
+
+module.exports = safeExec
+module.exports.promises = safeExecPromise
+
+// options are {timeout:  number-of-milliseconds, killSignal: signal-name}
+function safeExec(command, options, callback) {
+  if (!Settings.enableConversions) {
+    return callback(
+      new ConversionsDisabledError('image conversions are disabled')
+    )
+  }
+
+  const [cmd, ...args] = command
+
+  const child = childProcess.spawn(cmd, args, { detached: true })
+  let stdout = ''
+  let stderr = ''
+
+  let killTimer
+
+  const cleanup = lodashOnce(function (err) {
+    if (killTimer) {
+      clearTimeout(killTimer)
+    }
+    callback(err, stdout, stderr)
+  })
+
+  if (options.timeout) {
+    killTimer = setTimeout(function () {
+      try {
+        // use negative process id to kill process group
+        process.kill(-child.pid, options.killSignal || 'SIGTERM')
+      } catch (error) {
+        cleanup(
+          new FailedCommandError('failed to kill process after timeout', {
+            command,
+            options,
+            pid: child.pid,
+          })
+        )
+      }
+    }, options.timeout)
+  }
+
+  child.on('close', function (code, signal) {
+    if (code || signal) {
+      return cleanup(
+        new FailedCommandError(command, code || signal, stdout, stderr)
+      )
+    }
+
+    cleanup()
+  })
+
+  child.on('error', err => {
+    cleanup(err)
+  })
+  child.stdout.on('data', chunk => {
+    stdout += chunk
+  })
+  child.stderr.on('data', chunk => {
+    stderr += chunk
+  })
+}
+
+function safeExecPromise(command, options) {
+  return new Promise((resolve, reject) => {
+    safeExec(command, options, (err, stdout, stderr) => {
+      if (err) {
+        reject(err)
+      }
+      resolve({ stdout, stderr })
+    })
+  })
+}

services/filestore/buildscript.txt

@@ -0,0 +1,9 @@
+filestore
+--data-dirs=uploads,user_files,template_files
+--dependencies=s3,gcs
+--docker-repos=gcr.io/overleaf-ops
+--env-add=ENABLE_CONVERSIONS="true",USE_PROM_METRICS="true",AWS_S3_USER_FILES_BUCKET_NAME=fake_user_files,AWS_S3_TEMPLATE_FILES_BUCKET_NAME=fake_template_files,AWS_S3_PUBLIC_FILES_BUCKET_NAME=fake_public_files,GCS_USER_FILES_BUCKET_NAME=fake_userfiles,GCS_TEMPLATE_FILES_BUCKET_NAME=fake_templatefiles,GCS_PUBLIC_FILES_BUCKET_NAME=fake_publicfiles
+--env-pass-through=
+--node-version=12.22.3
+--public-repo=True
+--script-version=3.11.0

services/filestore/config/settings.defaults.js

@@ -0,0 +1,132 @@
+const Path = require('path')
+
+// environment variables renamed for consistency
+// use AWS_ACCESS_KEY_ID-style going forward
+if (process.env.AWS_KEY && !process.env.AWS_ACCESS_KEY_ID) {
+  process.env.AWS_ACCESS_KEY_ID = process.env.AWS_KEY
+}
+if (process.env.AWS_SECRET && !process.env.AWS_SECRET_ACCESS_KEY) {
+  process.env.AWS_SECRET_ACCESS_KEY = process.env.AWS_SECRET
+}
+
+// pre-backend setting, fall back to old behaviour
+if (process.env.BACKEND == null) {
+  if (process.env.AWS_ACCESS_KEY_ID || process.env.S3_BUCKET_CREDENTIALS) {
+    process.env.BACKEND = 's3'
+    process.env.USER_FILES_BUCKET_NAME =
+      process.env.AWS_S3_USER_FILES_BUCKET_NAME
+    process.env.TEMPLATE_FILES_BUCKET_NAME =
+      process.env.AWS_S3_TEMPLATE_FILES_BUCKET_NAME
+    process.env.PUBLIC_FILES_BUCKET_NAME =
+      process.env.AWS_S3_PUBLIC_FILES_BUCKET_NAME
+  } else {
+    process.env.BACKEND = 'fs'
+    process.env.USER_FILES_BUCKET_NAME = Path.resolve(
+      // eslint-disable-next-line no-path-concat
+      __dirname + '/../user_files'
+    )
+    process.env.TEMPLATE_FILES_BUCKET_NAME = Path.resolve(
+      // eslint-disable-next-line no-path-concat
+      __dirname + '/../template_files'
+    )
+    process.env.PUBLIC_FILES_BUCKET_NAME = Path.resolve(
+      // eslint-disable-next-line no-path-concat
+      __dirname + '/../public_files'
+    )
+  }
+}
+
+const settings = {
+  internal: {
+    filestore: {
+      port: 3009,
+      host: process.env.LISTEN_ADDRESS || 'localhost',
+    },
+  },
+
+  filestore: {
+    // Which backend persistor to use.
+    // Choices are
+    // s3 - Amazon S3
+    // fs - local filesystem
+    // gcs - Google Cloud Storage
+    backend: process.env.BACKEND,
+
+    gcs: {
+      endpoint: process.env.GCS_API_ENDPOINT
+        ? {
+            apiEndpoint: process.env.GCS_API_ENDPOINT,
+            apiScheme: process.env.GCS_API_SCHEME,
+            projectId: process.env.GCS_PROJECT_ID,
+          }
+        : undefined,
+      unlockBeforeDelete: process.env.GCS_UNLOCK_BEFORE_DELETE === 'true', // unlock an event-based hold before deleting. default false
+      deletedBucketSuffix: process.env.GCS_DELETED_BUCKET_SUFFIX, // if present, copy file to another bucket on delete. default null
+      deleteConcurrency: parseInt(process.env.GCS_DELETE_CONCURRENCY) || 50,
+      signedUrlExpiryInMs: parseInt(process.env.LINK_EXPIRY_TIMEOUT || 60000),
+    },
+
+    s3:
+      process.env.AWS_ACCESS_KEY_ID || process.env.S3_BUCKET_CREDENTIALS
+        ? {
+            key: process.env.AWS_ACCESS_KEY_ID,
+            secret: process.env.AWS_SECRET_ACCESS_KEY,
+            endpoint: process.env.AWS_S3_ENDPOINT,
+            pathStyle: process.env.AWS_S3_PATH_STYLE,
+            partSize: process.env.AWS_S3_PARTSIZE || 100 * 1024 * 1024,
+            bucketCreds: process.env.S3_BUCKET_CREDENTIALS
+              ? JSON.parse(process.env.S3_BUCKET_CREDENTIALS)
+              : undefined,
+          }
+        : undefined,
+
+    // GCS should be configured by the service account on the kubernetes pod. See GOOGLE_APPLICATION_CREDENTIALS,
+    // which will be picked up automatically.
+
+    stores: {
+      user_files: process.env.USER_FILES_BUCKET_NAME,
+      template_files: process.env.TEMPLATE_FILES_BUCKET_NAME,
+      public_files: process.env.PUBLIC_FILES_BUCKET_NAME,
+    },
+
+    fallback: process.env.FALLBACK_BACKEND
+      ? {
+          backend: process.env.FALLBACK_BACKEND,
+          // mapping of bucket names on the fallback, to bucket names on the primary.
+          // e.g. { myS3UserFilesBucketName: 'myGoogleUserFilesBucketName' }
+          buckets: JSON.parse(process.env.FALLBACK_BUCKET_MAPPING || '{}'),
+          copyOnMiss: process.env.COPY_ON_MISS === 'true',
+        }
+      : undefined,
+
+    allowRedirects: process.env.ALLOW_REDIRECTS === 'true',
+  },
+
+  path: {
+    // eslint-disable-next-line no-path-concat
+    uploadFolder: Path.resolve(__dirname + '/../uploads'),
+  },
+
+  commands: {
+    // Any commands to wrap the convert utility in, for example ["nice"], or ["firejail", "--profile=/etc/firejail/convert.profile"]
+    convertCommandPrefix: [],
+  },
+
+  enableConversions: process.env.ENABLE_CONVERSIONS === 'true',
+
+  sentry: {
+    dsn: process.env.SENTRY_DSN,
+  },
+}
+
+// Filestore health check
+// ----------------------
+// Project and file details to check in persistor when calling /health_check
+if (process.env.HEALTH_CHECK_PROJECT_ID && process.env.HEALTH_CHECK_FILE_ID) {
+  settings.health_check = {
+    project_id: process.env.HEALTH_CHECK_PROJECT_ID,
+    file_id: process.env.HEALTH_CHECK_FILE_ID,
+  }
+}
+
+module.exports = settings

services/filestore/docker-compose.ci.yml

@@ -0,0 +1,75 @@
+# This file was auto-generated, do not edit it directly.
+# Instead run bin/update_build_scripts from
+# https://github.com/sharelatex/sharelatex-dev-environment
+
+version: "2.3"
+
+services:
+  test_unit:
+    image: ci/$PROJECT_NAME:$BRANCH_NAME-$BUILD_NUMBER
+    user: node
+    command: npm run test:unit:_run
+    environment:
+      NODE_ENV: test
+      NODE_OPTIONS: "--unhandled-rejections=strict"
+
+
+  test_acceptance:
+    build: .
+    image: ci/$PROJECT_NAME:$BRANCH_NAME-$BUILD_NUMBER
+    environment:
+      ELASTIC_SEARCH_DSN: es:9200
+      REDIS_HOST: redis
+      QUEUES_REDIS_HOST: redis
+      MONGO_HOST: mongo
+      POSTGRES_HOST: postgres
+      AWS_S3_ENDPOINT: http://s3:9090
+      AWS_S3_PATH_STYLE: 'true'
+      AWS_ACCESS_KEY_ID: fake
+      AWS_SECRET_ACCESS_KEY: fake
+      GCS_API_ENDPOINT: gcs:9090
+      GCS_API_SCHEME: http
+      GCS_PROJECT_ID: fake
+      STORAGE_EMULATOR_HOST: http://gcs:9090/storage/v1
+      MOCHA_GREP: ${MOCHA_GREP}
+      NODE_ENV: test
+      NODE_OPTIONS: "--unhandled-rejections=strict"
+      ENABLE_CONVERSIONS: "true"
+      USE_PROM_METRICS: "true"
+      AWS_S3_USER_FILES_BUCKET_NAME: fake_user_files
+      AWS_S3_TEMPLATE_FILES_BUCKET_NAME: fake_template_files
+      AWS_S3_PUBLIC_FILES_BUCKET_NAME: fake_public_files
+      GCS_USER_FILES_BUCKET_NAME: fake_userfiles
+      GCS_TEMPLATE_FILES_BUCKET_NAME: fake_templatefiles
+      GCS_PUBLIC_FILES_BUCKET_NAME: fake_publicfiles
+    depends_on:
+      s3:
+        condition: service_healthy
+      gcs:
+        condition: service_healthy
+    user: node
+    command: npm run test:acceptance:_run
+
+
+  tar:
+    build: .
+    image: ci/$PROJECT_NAME:$BRANCH_NAME-$BUILD_NUMBER
+    volumes:
+      - ./:/tmp/build/
+    command: tar -czf /tmp/build/build.tar.gz --exclude=build.tar.gz --exclude-vcs .
+    user: root
+  s3:
+    image: adobe/s3mock
+    environment:
+      - initialBuckets=fake_user_files,fake_template_files,fake_public_files,bucket
+    healthcheck:
+      test: wget --quiet --output-document=/dev/null http://localhost:9090
+      interval: 1s
+      retries: 20
+  gcs:
+    image: fsouza/fake-gcs-server:v1.21.2
+    command: ["--port=9090", "--scheme=http"]
+    healthcheck:
+      test: wget --quiet --output-document=/dev/null http://localhost:9090/storage/v1/b
+      interval: 1s
+      retries: 20

services/filestore/docker-compose.yml

@@ -0,0 +1,77 @@
+# This file was auto-generated, do not edit it directly.
+# Instead run bin/update_build_scripts from
+# https://github.com/sharelatex/sharelatex-dev-environment
+
+version: "2.3"
+
+services:
+  test_unit:
+    build:
+      context: .
+      target: base
+    volumes:
+      - .:/app
+    working_dir: /app
+    environment:
+      MOCHA_GREP: ${MOCHA_GREP}
+      NODE_ENV: test
+      NODE_OPTIONS: "--unhandled-rejections=strict"
+    command: npm run --silent test:unit
+    user: node
+
+  test_acceptance:
+    build:
+      context: .
+      target: base
+    volumes:
+      - .:/app
+    working_dir: /app
+    environment:
+      ELASTIC_SEARCH_DSN: es:9200
+      REDIS_HOST: redis
+      QUEUES_REDIS_HOST: redis
+      MONGO_HOST: mongo
+      POSTGRES_HOST: postgres
+      AWS_S3_ENDPOINT: http://s3:9090
+      AWS_S3_PATH_STYLE: 'true'
+      AWS_ACCESS_KEY_ID: fake
+      AWS_SECRET_ACCESS_KEY: fake
+      GCS_API_ENDPOINT: gcs:9090
+      GCS_API_SCHEME: http
+      GCS_PROJECT_ID: fake
+      STORAGE_EMULATOR_HOST: http://gcs:9090/storage/v1
+      MOCHA_GREP: ${MOCHA_GREP}
+      LOG_LEVEL: ERROR
+      NODE_ENV: test
+      NODE_OPTIONS: "--unhandled-rejections=strict"
+      ENABLE_CONVERSIONS: "true"
+      USE_PROM_METRICS: "true"
+      AWS_S3_USER_FILES_BUCKET_NAME: fake_user_files
+      AWS_S3_TEMPLATE_FILES_BUCKET_NAME: fake_template_files
+      AWS_S3_PUBLIC_FILES_BUCKET_NAME: fake_public_files
+      GCS_USER_FILES_BUCKET_NAME: fake_userfiles
+      GCS_TEMPLATE_FILES_BUCKET_NAME: fake_templatefiles
+      GCS_PUBLIC_FILES_BUCKET_NAME: fake_publicfiles
+    user: node
+    depends_on:
+      s3:
+        condition: service_healthy
+      gcs:
+        condition: service_healthy
+    command: npm run --silent test:acceptance
+
+  s3:
+    image: adobe/s3mock
+    environment:
+      - initialBuckets=fake_user_files,fake_template_files,fake_public_files,bucket
+    healthcheck:
+      test: wget --quiet --output-document=/dev/null http://localhost:9090
+      interval: 1s
+      retries: 20
+  gcs:
+    image: fsouza/fake-gcs-server:v1.21.2
+    command: ["--port=9090", "--scheme=http"]
+    healthcheck:
+      test: wget --quiet --output-document=/dev/null http://localhost:9090/storage/v1/b
+      interval: 1s
+      retries: 20

services/filestore/firejail/convert.profile

@@ -0,0 +1,40 @@
+# Convert (ImageMagick profile)
+
+include /etc/firejail/disable-common.inc
+include /etc/firejail/disable-devel.inc
+# include /etc/firejail/disable-mgmt.inc ## removed in firejail 0.9.40
+# include /etc/firejail/disable-secret.inc ## removed in firejail 0.9.40
+
+read-only /bin
+blacklist /boot
+blacklist /dev
+read-only /etc
+read-only /home
+read-only /lib
+read-only /lib64
+blacklist /media
+blacklist /mnt
+blacklist /opt
+blacklist /root
+read-only /run
+blacklist /sbin
+blacklist /selinux
+blacklist /src
+blacklist /sys
+read-only /usr
+blacklist /var
+
+caps.drop all
+noroot
+nogroups
+protocol unix
+net none
+private-tmp
+private-dev
+shell none
+
+seccomp.keep accept,accept4,access,alarm,arch_prctl,bind,brk,capget,capset,chdir,chmod,chown,chroot,clock_getres,clock_gettime,clock_nanosleep,clone,close,connect,creat,dup,dup2,dup3,epoll_create,epoll_create1,epoll_ctl,epoll_ctl_old,epoll_pwait,epoll_wait,epoll_wait_old,eventfd,eventfd2,execve,execveat,exit,exit_group,faccessat,fadvise64,fallocate,fanotify_init,fanotify_mark,fchdir,fchmod,fchmodat,fchown,fchownat,fcntl,fdatasync,fgetxattr,flistxattr,flock,fork,fremovexattr,fsetxattr,fstat,fstatfs,fsync,ftruncate,futex,futimesat,get_robust_list,get_thread_area,getcpu,getcwd,getdents,getdents64,getegid,geteuid,getgid,getgroups,getitimer,getpeername,getpgid,getpgrp,getpid,getppid,getpriority,getrandom,getresgid,getresuid,getrlimit,getrusage,getsid,getsockname,getsockopt,gettid,gettimeofday,getuid,getxattr,inotify_add_watch,inotify_init,inotify_init1,inotify_rm_watch,io_cancel,io_destroy,io_getevents,io_setup,io_submit,ioctl,ioprio_get,ioprio_set,kill,lchown,lgetxattr,link,linkat,listen,listxattr,llistxattr,lremovexattr,lseek,lsetxattr,lstat,madvise,memfd_create,mincore,mkdir,mkdirat,mknod,mknodat,mlock,mlockall,mmap,modify_ldt,mprotect,mq_getsetattr,mq_notify,mq_open,mq_timedreceive,mq_timedsend,mq_unlink,mremap,msgctl,msgget,msgrcv,msgsnd,msync,munlock,munlockall,munmap,nanosleep,newfstatat,open,openat,pause,personality,pipe,pipe2,poll,ppoll,prctl,pread64,preadv,prlimit64,pselect6,pwrite64,pwritev,read,readahead,readlink,readlinkat,readv,recvfrom,recvmmsg,recvmsg,remap_file_pages,removexattr,rename,renameat,renameat2,restart_syscall,rmdir,rt_sigaction,rt_sigpending,rt_sigprocmask,rt_sigqueueinfo,rt_sigreturn,rt_sigsuspend,rt_sigtimedwait,rt_tgsigqueueinfo,sched_get_priority_max,sched_get_priority_min,sched_getaffinity,sched_getattr,sched_getparam,sched_getscheduler,sched_rr_get_interval,sched_setaffinity,sched_setattr,sched_setparam,sched_setscheduler,sched_yield,seccomp,select,semctl,semget,semop,semtimedop,sendfile,sendmmsg,sendmsg,sendto,set_robust_list,set_thread_area,set_tid_address,setdomainname,setfsgid,setfsuid,setgid,setgroups,sethostname,setitimer,setpgid,setpriority,setregid,setresgid,setresuid,setreuid,setrlimit,setsid,setsockopt,setuid,setxattr,shmat,shmctl,shmdt,shmget,shutdown,sigaltstack,signalfd,signalfd4,socket,socketpair,splice,stat,statfs,symlink,symlinkat,sync,sync_file_range,syncfs,sysinfo,syslog,tee,tgkill,time,timer_create,timer_delete,timer_getoverrun,timer_gettime,timer_settime,timerfd_create,timerfd_gettime,timerfd_settime,times,tkill,truncate,umask,uname,unlink,unlinkat,utime,utimensat,utimes,vfork,vhangup,vmsplice,wait4,waitid,write,writev,unshare
+
+rlimit-fsize 524288000 #500Mb
+rlimit-nproc 600 #if too low this can cause error: Error fork:sandbox(774): Resource temporarily unavailable
+rlimit-nofile 100

services/filestore/install_deps.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+set -ex
+
+apt-get update
+
+apt-get install ghostscript imagemagick optipng --yes
+
+rm -rf /var/lib/apt/lists/*

services/filestore/nodemon.json

@@ -0,0 +1,17 @@
+{
+  "ignore": [
+    ".git",
+    "node_modules/"
+  ],
+  "verbose": true,
+  "legacyWatch": true,
+  "execMap": {
+    "js": "npm run start"
+  },
+  "watch": [
+    "app/js/",
+    "app.js",
+    "config/"
+  ],
+  "ext": "js"
+}

services/filestore/package.json

@@ -0,0 +1,68 @@
+{
+  "name": "filestore-sharelatex",
+  "version": "0.1.4",
+  "description": "An API for CRUD operations on binary files stored in S3",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/sharelatex/filestore-sharelatex.git"
+  },
+  "scripts": {
+    "test:acceptance:run": "mocha --recursive --reporter spec --timeout 15000  $@ test/acceptance/js",
+    "test:acceptance": "npm run test:acceptance:_run -- --grep=$MOCHA_GREP",
+    "test:unit:run": "mocha --recursive --reporter spec $@ test/unit/js",
+    "test:unit": "npm run test:unit:_run -- --grep=$MOCHA_GREP",
+    "start": "node $NODE_APP_OPTIONS app.js",
+    "nodemon": "nodemon --config nodemon.json",
+    "lint": "eslint --max-warnings 0 --format unix .",
+    "format": "prettier --list-different $PWD/'**/*.js'",
+    "format:fix": "prettier --write $PWD/'**/*.js'",
+    "test:acceptance:_run": "mocha --recursive --reporter spec --timeout 15000 --exit $@ test/acceptance/js",
+    "test:unit:_run": "mocha --recursive --reporter spec $@ test/unit/js",
+    "lint:fix": "eslint --fix ."
+  },
+  "dependencies": {
+    "@overleaf/metrics": "^3.5.1",
+    "@overleaf/o-error": "^3.0.0",
+    "@overleaf/object-persistor": "https://github.com/overleaf/object-persistor/archive/8fbc9ed03206bfb54368578d22b7ac4f285baa25.tar.gz",
+    "@overleaf/settings": "^2.1.1",
+    "body-parser": "^1.19.0",
+    "bunyan": "^1.8.15",
+    "express": "^4.17.1",
+    "fast-crc32c": "^2.0.0",
+    "glob": "^7.1.6",
+    "lodash.once": "^4.1.1",
+    "logger-sharelatex": "^2.2.0",
+    "node-uuid": "~1.4.8",
+    "range-parser": "^1.2.1",
+    "request": "^2.88.2",
+    "request-promise-native": "^1.0.8",
+    "stream-buffers": "~0.2.6",
+    "tiny-async-pool": "^1.1.0"
+  },
+  "devDependencies": {
+    "@google-cloud/storage": "^5.1.2",
+    "aws-sdk": "^2.718.0",
+    "chai": "^4.2.0",
+    "chai-as-promised": "^7.1.1",
+    "disrequire": "^1.1.0",
+    "eslint": "^7.21.0",
+    "eslint-config-prettier": "^8.1.0",
+    "eslint-config-standard": "^16.0.2",
+    "eslint-plugin-chai-expect": "^2.2.0",
+    "eslint-plugin-chai-friendly": "^0.6.0",
+    "eslint-plugin-import": "^2.22.1",
+    "eslint-plugin-mocha": "^8.0.0",
+    "eslint-plugin-node": "^11.1.0",
+    "eslint-plugin-prettier": "^3.1.2",
+    "eslint-plugin-promise": "^4.2.1",
+    "mocha": "^8.3.2",
+    "mongodb": "^3.5.9",
+    "prettier": "^2.2.1",
+    "prettier-eslint": "^9.0.2",
+    "sandboxed-module": "2.0.4",
+    "sinon": "9.0.2",
+    "sinon-chai": "^3.5.0",
+    "streamifier": "^0.1.1",
+    "timekeeper": "^2.2.0"
+  }
+}

services/filestore/test/acceptance/deps/Dockerfile.fake-gcs

@@ -0,0 +1,5 @@
+FROM fsouza/fake-gcs-server:1.20
+RUN apk add --update --no-cache curl
+COPY healthcheck.sh /healthcheck.sh
+HEALTHCHECK --interval=1s --timeout=1s --retries=30 CMD /healthcheck.sh http://localhost:9090
+CMD ["--port=9090", "--scheme=http"]

services/filestore/test/acceptance/deps/Dockerfile.s3mock

@@ -0,0 +1,4 @@
+FROM adobe/s3mock
+RUN apk add --update --no-cache curl
+COPY healthcheck.sh /healthcheck.sh
+HEALTHCHECK --interval=1s --timeout=1s --retries=30 CMD /healthcheck.sh http://localhost:9090

services/filestore/test/acceptance/deps/healthcheck.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+# health check to allow 404 status code as valid
+STATUSCODE=$(curl --silent --output /dev/null --write-out "%{http_code}" $1)
+# will be 000 on non-http error (e.g. connection failure)
+if test $STATUSCODE -ge 500 || test $STATUSCODE -lt 200; then
+  exit 1
+fi
+exit 0

services/filestore/test/acceptance/js/FilestoreApp.js

@@ -0,0 +1,123 @@
+const logger = require('logger-sharelatex')
+const Settings = require('@overleaf/settings')
+const fs = require('fs')
+const Path = require('path')
+const { promisify } = require('util')
+const disrequire = require('disrequire')
+const AWS = require('aws-sdk')
+
+logger.logger.level('info')
+
+const fsReaddir = promisify(fs.readdir)
+const sleep = promisify(setTimeout)
+
+class FilestoreApp {
+  constructor() {
+    this.running = false
+    this.initing = false
+  }
+
+  async runServer() {
+    if (this.running) {
+      return
+    }
+
+    if (this.initing) {
+      return this.waitForInit()
+    }
+    this.initing = true
+
+    this.app = await FilestoreApp.requireApp()
+
+    await new Promise((resolve, reject) => {
+      this.server = this.app.listen(
+        Settings.internal.filestore.port,
+        'localhost',
+        err => {
+          if (err) {
+            return reject(err)
+          }
+          resolve()
+        }
+      )
+    })
+
+    if (Settings.filestore.backend === 's3') {
+      try {
+        await FilestoreApp.waitForS3()
+      } catch (err) {
+        await this.stop()
+        throw err
+      }
+    }
+
+    this.initing = false
+    this.persistor = require('../../../app/js/PersistorManager')
+  }
+
+  async waitForInit() {
+    while (this.initing) {
+      await sleep(1000)
+    }
+  }
+
+  async stop() {
+    if (!this.server) return
+    const closeServer = promisify(this.server.close).bind(this.server)
+    try {
+      await closeServer()
+    } finally {
+      delete this.server
+    }
+  }
+
+  static async waitForS3() {
+    let tries = 0
+    if (!Settings.filestore.s3.endpoint) {
+      return
+    }
+
+    const s3 = new AWS.S3({
+      accessKeyId: Settings.filestore.s3.key,
+      secretAccessKey: Settings.filestore.s3.secret,
+      endpoint: Settings.filestore.s3.endpoint,
+      s3ForcePathStyle: true,
+      signatureVersion: 'v4',
+    })
+
+    while (true) {
+      try {
+        return await s3
+          .putObject({
+            Key: 'startup',
+            Body: '42',
+            Bucket: Settings.filestore.stores.user_files,
+          })
+          .promise()
+      } catch (err) {
+        // swallow errors, as we may experience them until fake-s3 is running
+        if (tries === 9) {
+          // throw just before hitting the 10s test timeout
+          throw err
+        }
+        tries++
+        await sleep(1000)
+      }
+    }
+  }
+
+  static async requireApp() {
+    // unload the app, as we may be doing this on multiple runs with
+    // different settings, which affect startup in some cases
+    const files = await fsReaddir(Path.resolve(__dirname, '../../../app/js'))
+    files.forEach(file => {
+      disrequire(Path.resolve(__dirname, '../../../app/js', file))
+    })
+    disrequire(Path.resolve(__dirname, '../../../app'))
+    disrequire('@overleaf/object-persistor')
+
+    return require('../../../app')
+  }
+}
+
+module.exports = FilestoreApp

services/filestore/test/acceptance/js/FilestoreTests.js

@@ -0,0 +1,932 @@
+const chai = require('chai')
+const { expect } = chai
+const fs = require('fs')
+const Settings = require('@overleaf/settings')
+const Path = require('path')
+const FilestoreApp = require('./FilestoreApp')
+const TestHelper = require('./TestHelper')
+const rp = require('request-promise-native').defaults({
+  resolveWithFullResponse: true,
+})
+const S3 = require('aws-sdk/clients/s3')
+const Stream = require('stream')
+const request = require('request')
+const { promisify } = require('util')
+const { Storage } = require('@google-cloud/storage')
+const streamifier = require('streamifier')
+chai.use(require('chai-as-promised'))
+const { ObjectId } = require('mongodb')
+const tk = require('timekeeper')
+const ChildProcess = require('child_process')
+
+const fsWriteFile = promisify(fs.writeFile)
+const fsStat = promisify(fs.stat)
+const pipeline = promisify(Stream.pipeline)
+const exec = promisify(ChildProcess.exec)
+const msleep = promisify(setTimeout)
+
+if (!process.env.AWS_ACCESS_KEY_ID) {
+  throw new Error('please provide credentials for the AWS S3 test server')
+}
+
+process.on('unhandledRejection', e => {
+  // eslint-disable-next-line no-console
+  console.log('** Unhandled Promise Rejection **\n', e)
+  throw e
+})
+
+// store settings for multiple backends, so that we can test each one.
+// fs will always be available - add others if they are configured
+const BackendSettings = require('./TestConfig')
+
+describe('Filestore', function () {
+  this.timeout(1000 * 10)
+  const filestoreUrl = `http://localhost:${Settings.internal.filestore.port}`
+
+  const seenSockets = []
+  async function expectNoSockets() {
+    try {
+      await msleep(1000)
+      const { stdout } = await exec('ss -tnH')
+
+      const badSockets = []
+      for (const socket of stdout.split('\n')) {
+        const fields = socket.split(' ').filter(part => part !== '')
+        if (
+          fields.length > 2 &&
+          parseInt(fields[1]) &&
+          !seenSockets.includes(socket)
+        ) {
+          badSockets.push(socket)
+          seenSockets.push(socket)
+        }
+      }
+
+      if (badSockets.length) {
+        // eslint-disable-next-line no-console
+        console.error(
+          'ERR: Sockets still have receive buffer after connection closed'
+        )
+        for (const socket of badSockets) {
+          // eslint-disable-next-line no-console
+          console.error(socket)
+        }
+        throw new Error('Sockets still open after connection closed')
+      }
+    } catch (err) {
+      expect(err).not.to.exist
+    }
+  }
+
+  // redefine the test suite for every available backend
+  Object.keys(BackendSettings).forEach(backend => {
+    describe(backend, function () {
+      let app, previousEgress, previousIngress, metricPrefix, projectId
+
+      before(async function () {
+        // create the app with the relevant filestore settings
+        Settings.filestore = BackendSettings[backend]
+        app = new FilestoreApp()
+        await app.runServer()
+      })
+
+      if (BackendSettings[backend].gcs) {
+        before(async function () {
+          const storage = new Storage(Settings.filestore.gcs.endpoint)
+          await storage.createBucket(process.env.GCS_USER_FILES_BUCKET_NAME)
+          await storage.createBucket(process.env.GCS_PUBLIC_FILES_BUCKET_NAME)
+          await storage.createBucket(process.env.GCS_TEMPLATE_FILES_BUCKET_NAME)
+          await storage.createBucket(
+            `${process.env.GCS_USER_FILES_BUCKET_NAME}-deleted`
+          )
+          await storage.createBucket(
+            `${process.env.GCS_PUBLIC_FILES_BUCKET_NAME}-deleted`
+          )
+          await storage.createBucket(
+            `${process.env.GCS_TEMPLATE_FILES_BUCKET_NAME}-deleted`
+          )
+        })
+      }
+
+      after(async function () {
+        await msleep(3000)
+        await app.stop()
+      })
+
+      beforeEach(async function () {
+        // retrieve previous metrics from the app
+        if (['s3', 'gcs'].includes(Settings.filestore.backend)) {
+          metricPrefix = Settings.filestore.backend
+          previousEgress = await TestHelper.getMetric(
+            filestoreUrl,
+            `${metricPrefix}_egress`
+          )
+        }
+        projectId = ObjectId().toString()
+      })
+
+      it('should send a 200 for the status endpoint', async function () {
+        const response = await rp(`${filestoreUrl}/status`)
+        expect(response.statusCode).to.equal(200)
+        expect(response.body).to.contain('filestore')
+        expect(response.body).to.contain('up')
+      })
+
+      it('should send a 200 for the health-check endpoint', async function () {
+        const response = await rp(`${filestoreUrl}/health_check`)
+        expect(response.statusCode).to.equal(200)
+        expect(response.body).to.equal('OK')
+      })
+
+      describe('with a file on the server', function () {
+        let fileId, fileUrl, constantFileContent
+
+        const localFileReadPath =
+          '/tmp/filestore_acceptance_tests_file_read.txt'
+
+        beforeEach(async function () {
+          fileId = ObjectId().toString()
+          fileUrl = `${filestoreUrl}/project/${projectId}/file/${fileId}`
+          constantFileContent = [
+            'hello world',
+            `line 2 goes here ${Math.random()}`,
+            'there are 3 lines in all',
+          ].join('\n')
+
+          await fsWriteFile(localFileReadPath, constantFileContent)
+
+          const writeStream = request.post(fileUrl)
+          const readStream = fs.createReadStream(localFileReadPath)
+          // hack to consume the result to ensure the http request has been fully processed
+          const resultStream = fs.createWriteStream('/dev/null')
+          await pipeline(readStream, writeStream, resultStream)
+        })
+
+        beforeEach(async function retrievePreviousIngressMetrics() {
+          // The upload request can bump the ingress metric.
+          // The content hash validation might require a full download
+          //  in case the ETag field of the upload response is not a md5 sum.
+          if (['s3', 'gcs'].includes(Settings.filestore.backend)) {
+            previousIngress = await TestHelper.getMetric(
+              filestoreUrl,
+              `${metricPrefix}_ingress`
+            )
+          }
+        })
+
+        it('should return 404 for a non-existant id', async function () {
+          const options = { uri: fileUrl + '___this_is_clearly_wrong___' }
+          await expect(
+            rp.get(options)
+          ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+        })
+
+        it('should return the file size on a HEAD request', async function () {
+          const expectedLength = Buffer.byteLength(constantFileContent)
+          const res = await rp.head(fileUrl)
+          expect(res.statusCode).to.equal(200)
+          expect(res.headers['content-length']).to.equal(
+            expectedLength.toString()
+          )
+        })
+
+        it('should be able get the file back', async function () {
+          const res = await rp.get(fileUrl)
+          expect(res.body).to.equal(constantFileContent)
+        })
+
+        it('should not leak a socket', async function () {
+          await rp.get(fileUrl)
+          await expectNoSockets()
+        })
+
+        it('should be able to get back the first 9 bytes of the file', async function () {
+          const options = {
+            uri: fileUrl,
+            headers: {
+              Range: 'bytes=0-8',
+            },
+          }
+          const res = await rp.get(options)
+          expect(res.body).to.equal('hello wor')
+        })
+
+        it('should be able to get back bytes 4 through 10 of the file', async function () {
+          const options = {
+            uri: fileUrl,
+            headers: {
+              Range: 'bytes=4-10',
+            },
+          }
+          const res = await rp.get(options)
+          expect(res.body).to.equal('o world')
+        })
+
+        it('should be able to delete the file', async function () {
+          const response = await rp.del(fileUrl)
+          expect(response.statusCode).to.equal(204)
+          await expect(
+            rp.get(fileUrl)
+          ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+        })
+
+        it('should be able to copy files', async function () {
+          const newProjectID = ObjectId().toString()
+          const newFileId = ObjectId().toString()
+          const newFileUrl = `${filestoreUrl}/project/${newProjectID}/file/${newFileId}`
+          const opts = {
+            method: 'put',
+            uri: newFileUrl,
+            json: {
+              source: {
+                project_id: projectId,
+                file_id: fileId,
+              },
+            },
+          }
+          let response = await rp(opts)
+          expect(response.statusCode).to.equal(200)
+          response = await rp.del(fileUrl)
+          expect(response.statusCode).to.equal(204)
+          response = await rp.get(newFileUrl)
+          expect(response.body).to.equal(constantFileContent)
+        })
+
+        it('should be able to overwrite the file', async function () {
+          const newContent = `here is some different content, ${Math.random()}`
+          const writeStream = request.post(fileUrl)
+          const readStream = streamifier.createReadStream(newContent)
+          // hack to consume the result to ensure the http request has been fully processed
+          const resultStream = fs.createWriteStream('/dev/null')
+          await pipeline(readStream, writeStream, resultStream)
+
+          const response = await rp.get(fileUrl)
+          expect(response.body).to.equal(newContent)
+        })
+
+        if (['S3Persistor', 'GcsPersistor'].includes(backend)) {
+          it('should record an egress metric for the upload', async function () {
+            const metric = await TestHelper.getMetric(
+              filestoreUrl,
+              `${metricPrefix}_egress`
+            )
+            expect(metric - previousEgress).to.equal(constantFileContent.length)
+          })
+
+          it('should record an ingress metric when downloading the file', async function () {
+            await rp.get(fileUrl)
+            const metric = await TestHelper.getMetric(
+              filestoreUrl,
+              `${metricPrefix}_ingress`
+            )
+            expect(metric - previousIngress).to.equal(
+              constantFileContent.length
+            )
+          })
+
+          it('should record an ingress metric for a partial download', async function () {
+            const options = {
+              uri: fileUrl,
+              headers: {
+                Range: 'bytes=0-8',
+              },
+            }
+            await rp.get(options)
+            const metric = await TestHelper.getMetric(
+              filestoreUrl,
+              `${metricPrefix}_ingress`
+            )
+            expect(metric - previousIngress).to.equal(9)
+          })
+        }
+      })
+
+      describe('with multiple files', function () {
+        let fileIds, fileUrls, projectUrl
+        const localFileReadPaths = [
+          '/tmp/filestore_acceptance_tests_file_read_1.txt',
+          '/tmp/filestore_acceptance_tests_file_read_2.txt',
+        ]
+        const constantFileContents = [
+          [
+            'hello world',
+            `line 2 goes here ${Math.random()}`,
+            'there are 3 lines in all',
+          ].join('\n'),
+          [
+            `for reference: ${Math.random()}`,
+            'cats are the best animals',
+            'wombats are a close second',
+          ].join('\n'),
+        ]
+
+        before(async function () {
+          return Promise.all([
+            fsWriteFile(localFileReadPaths[0], constantFileContents[0]),
+            fsWriteFile(localFileReadPaths[1], constantFileContents[1]),
+          ])
+        })
+
+        beforeEach(async function () {
+          projectUrl = `${filestoreUrl}/project/${projectId}`
+          fileIds = [ObjectId().toString(), ObjectId().toString()]
+          fileUrls = [
+            `${projectUrl}/file/${fileIds[0]}`,
+            `${projectUrl}/file/${fileIds[1]}`,
+          ]
+
+          const writeStreams = [
+            request.post(fileUrls[0]),
+            request.post(fileUrls[1]),
+          ]
+          const readStreams = [
+            fs.createReadStream(localFileReadPaths[0]),
+            fs.createReadStream(localFileReadPaths[1]),
+          ]
+          // hack to consume the result to ensure the http request has been fully processed
+          const resultStreams = [
+            fs.createWriteStream('/dev/null'),
+            fs.createWriteStream('/dev/null'),
+          ]
+          return Promise.all([
+            pipeline(readStreams[0], writeStreams[0], resultStreams[0]),
+            pipeline(readStreams[1], writeStreams[1], resultStreams[1]),
+          ])
+        })
+
+        it('should get the directory size', async function () {
+          const response = await rp.get(
+            `${filestoreUrl}/project/${projectId}/size`
+          )
+          expect(parseInt(JSON.parse(response.body)['total bytes'])).to.equal(
+            constantFileContents[0].length + constantFileContents[1].length
+          )
+        })
+
+        it('should store the files', async function () {
+          for (const index in fileUrls) {
+            await expect(rp.get(fileUrls[index])).to.eventually.have.property(
+              'body',
+              constantFileContents[index]
+            )
+          }
+        })
+
+        it('should be able to delete the project', async function () {
+          await expect(rp.delete(projectUrl)).to.eventually.have.property(
+            'statusCode',
+            204
+          )
+
+          for (const index in fileUrls) {
+            await expect(
+              rp.get(fileUrls[index])
+            ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+          }
+        })
+
+        it('should not delete a partial project id', async function () {
+          await expect(
+            rp.delete(`${filestoreUrl}/project/5`)
+          ).to.eventually.be.rejected.and.have.property('statusCode', 400)
+        })
+      })
+
+      describe('with a large file', function () {
+        let fileId, fileUrl, largeFileContent, error
+
+        beforeEach(async function () {
+          fileId = ObjectId().toString()
+          fileUrl = `${filestoreUrl}/project/${projectId}/file/${fileId}`
+
+          largeFileContent = '_wombat_'.repeat(1024 * 1024) // 8 megabytes
+          largeFileContent += Math.random()
+
+          const writeStream = request.post(fileUrl)
+          const readStream = streamifier.createReadStream(largeFileContent)
+          // hack to consume the result to ensure the http request has been fully processed
+          const resultStream = fs.createWriteStream('/dev/null')
+
+          try {
+            await pipeline(readStream, writeStream, resultStream)
+          } catch (err) {
+            error = err
+          }
+        })
+
+        it('should be able to get the file back', async function () {
+          const response = await rp.get(fileUrl)
+          expect(response.body).to.equal(largeFileContent)
+        })
+
+        it('should not throw an error', function () {
+          expect(error).not.to.exist
+        })
+
+        it('should not leak a socket', async function () {
+          await rp.get(fileUrl)
+          await expectNoSockets()
+        })
+
+        it('should not leak a socket if the connection is aborted', async function () {
+          this.timeout(20000)
+          for (let i = 0; i < 5; i++) {
+            // test is not 100% reliable, so repeat
+            // create a new connection and have it time out before reading any data
+            await new Promise(resolve => {
+              const streamThatHangs = new Stream.PassThrough()
+              const stream = request({ url: fileUrl, timeout: 1000 })
+              stream.pipe(streamThatHangs)
+              stream.on('error', () => {
+                stream.destroy()
+                streamThatHangs.destroy()
+                resolve()
+              })
+            })
+            await expectNoSockets()
+          }
+        })
+      })
+
+      if (backend === 'S3Persistor' || backend === 'FallbackGcsToS3Persistor') {
+        describe('with a file in a specific bucket', function () {
+          let constantFileContent, fileId, fileUrl, bucketName
+
+          beforeEach(async function () {
+            constantFileContent = `This is a file in a different S3 bucket ${Math.random()}`
+            fileId = ObjectId().toString()
+            bucketName = ObjectId().toString()
+            fileUrl = `${filestoreUrl}/bucket/${bucketName}/key/${fileId}`
+
+            const s3ClientSettings = {
+              credentials: {
+                accessKeyId: process.env.AWS_ACCESS_KEY_ID,
+                secretAccessKey: process.env.AWS_SECRET_ACCESS_KEY,
+              },
+              endpoint: process.env.AWS_S3_ENDPOINT,
+              sslEnabled: false,
+              s3ForcePathStyle: true,
+            }
+
+            const s3 = new S3(s3ClientSettings)
+            await s3
+              .createBucket({
+                Bucket: bucketName,
+              })
+              .promise()
+            await s3
+              .upload({
+                Bucket: bucketName,
+                Key: fileId,
+                Body: constantFileContent,
+              })
+              .promise()
+          })
+
+          it('should get the file from the specified bucket', async function () {
+            const response = await rp.get(fileUrl)
+            expect(response.body).to.equal(constantFileContent)
+          })
+        })
+      }
+
+      if (backend === 'GcsPersistor') {
+        describe('when deleting a file in GCS', function () {
+          let fileId, fileUrl, content, error, date
+
+          beforeEach(async function () {
+            date = new Date()
+            tk.freeze(date)
+            fileId = ObjectId()
+            fileUrl = `${filestoreUrl}/project/${projectId}/file/${fileId}`
+
+            content = '_wombat_' + Math.random()
+
+            const writeStream = request.post(fileUrl)
+            const readStream = streamifier.createReadStream(content)
+            // hack to consume the result to ensure the http request has been fully processed
+            const resultStream = fs.createWriteStream('/dev/null')
+
+            try {
+              await pipeline(readStream, writeStream, resultStream)
+              await rp.delete(fileUrl)
+            } catch (err) {
+              error = err
+            }
+          })
+
+          afterEach(function () {
+            tk.reset()
+          })
+
+          it('should not throw an error', function () {
+            expect(error).not.to.exist
+          })
+
+          it('should copy the file to the deleted-files bucket', async function () {
+            await TestHelper.expectPersistorToHaveFile(
+              app.persistor,
+              `${Settings.filestore.stores.user_files}-deleted`,
+              `${projectId}/${fileId}-${date.toISOString()}`,
+              content
+            )
+          })
+
+          it('should remove the file from the original bucket', async function () {
+            await TestHelper.expectPersistorNotToHaveFile(
+              app.persistor,
+              Settings.filestore.stores.user_files,
+              `${projectId}/${fileId}`
+            )
+          })
+        })
+      }
+
+      if (BackendSettings[backend].fallback) {
+        describe('with a fallback', function () {
+          let constantFileContent,
+            fileId,
+            fileKey,
+            fileUrl,
+            bucket,
+            fallbackBucket
+
+          beforeEach(function () {
+            constantFileContent = `This is yet more file content ${Math.random()}`
+            fileId = ObjectId().toString()
+            fileKey = `${projectId}/${fileId}`
+            fileUrl = `${filestoreUrl}/project/${projectId}/file/${fileId}`
+
+            bucket = Settings.filestore.stores.user_files
+            fallbackBucket = Settings.filestore.fallback.buckets[bucket]
+          })
+
+          describe('with a file in the fallback bucket', function () {
+            beforeEach(async function () {
+              await TestHelper.uploadStringToPersistor(
+                app.persistor.fallbackPersistor,
+                fallbackBucket,
+                fileKey,
+                constantFileContent
+              )
+            })
+
+            it('should not find file in the primary', async function () {
+              await TestHelper.expectPersistorNotToHaveFile(
+                app.persistor.primaryPersistor,
+                bucket,
+                fileKey
+              )
+            })
+
+            it('should find the file in the fallback', async function () {
+              await TestHelper.expectPersistorToHaveFile(
+                app.persistor.fallbackPersistor,
+                fallbackBucket,
+                fileKey,
+                constantFileContent
+              )
+            })
+
+            describe('when copyOnMiss is disabled', function () {
+              beforeEach(function () {
+                app.persistor.settings.copyOnMiss = false
+              })
+
+              it('should fetch the file', async function () {
+                const res = await rp.get(fileUrl)
+                expect(res.body).to.equal(constantFileContent)
+              })
+
+              it('should not copy the file to the primary', async function () {
+                await rp.get(fileUrl)
+
+                await TestHelper.expectPersistorNotToHaveFile(
+                  app.persistor.primaryPersistor,
+                  bucket,
+                  fileKey
+                )
+              })
+            })
+
+            describe('when copyOnMiss is enabled', function () {
+              beforeEach(function () {
+                app.persistor.settings.copyOnMiss = true
+              })
+
+              it('should fetch the file', async function () {
+                const res = await rp.get(fileUrl)
+                expect(res.body).to.equal(constantFileContent)
+              })
+
+              it('copies the file to the primary', async function () {
+                await rp.get(fileUrl)
+                // wait for the file to copy in the background
+                await msleep(1000)
+
+                await TestHelper.expectPersistorToHaveFile(
+                  app.persistor.primaryPersistor,
+                  bucket,
+                  fileKey,
+                  constantFileContent
+                )
+              })
+            })
+
+            describe('when copying a file', function () {
+              let newFileId, newFileUrl, newFileKey, opts
+
+              beforeEach(function () {
+                const newProjectID = ObjectId().toString()
+                newFileId = ObjectId().toString()
+                newFileUrl = `${filestoreUrl}/project/${newProjectID}/file/${newFileId}`
+                newFileKey = `${newProjectID}/${newFileId}`
+
+                opts = {
+                  method: 'put',
+                  uri: newFileUrl,
+                  json: {
+                    source: {
+                      project_id: projectId,
+                      file_id: fileId,
+                    },
+                  },
+                }
+              })
+
+              describe('when copyOnMiss is false', function () {
+                beforeEach(async function () {
+                  app.persistor.settings.copyOnMiss = false
+
+                  const response = await rp(opts)
+                  expect(response.statusCode).to.equal(200)
+                })
+
+                it('should leave the old file in the old bucket', async function () {
+                  await TestHelper.expectPersistorToHaveFile(
+                    app.persistor.fallbackPersistor,
+                    fallbackBucket,
+                    fileKey,
+                    constantFileContent
+                  )
+                })
+
+                it('should not create a new file in the old bucket', async function () {
+                  await TestHelper.expectPersistorNotToHaveFile(
+                    app.persistor.fallbackPersistor,
+                    fallbackBucket,
+                    newFileKey
+                  )
+                })
+
+                it('should create a new file in the new bucket', async function () {
+                  await TestHelper.expectPersistorToHaveFile(
+                    app.persistor.primaryPersistor,
+                    bucket,
+                    newFileKey,
+                    constantFileContent
+                  )
+                })
+
+                it('should not copy the old file to the primary with the old key', async function () {
+                  // wait for the file to copy in the background
+                  await msleep(1000)
+
+                  await TestHelper.expectPersistorNotToHaveFile(
+                    app.persistor.primaryPersistor,
+                    bucket,
+                    fileKey
+                  )
+                })
+              })
+
+              describe('when copyOnMiss is true', function () {
+                beforeEach(async function () {
+                  app.persistor.settings.copyOnMiss = true
+
+                  const response = await rp(opts)
+                  expect(response.statusCode).to.equal(200)
+                })
+
+                it('should leave the old file in the old bucket', async function () {
+                  await TestHelper.expectPersistorToHaveFile(
+                    app.persistor.fallbackPersistor,
+                    fallbackBucket,
+                    fileKey,
+                    constantFileContent
+                  )
+                })
+
+                it('should not create a new file in the old bucket', async function () {
+                  await TestHelper.expectPersistorNotToHaveFile(
+                    app.persistor.fallbackPersistor,
+                    fallbackBucket,
+                    newFileKey
+                  )
+                })
+
+                it('should create a new file in the new bucket', async function () {
+                  await TestHelper.expectPersistorToHaveFile(
+                    app.persistor.primaryPersistor,
+                    bucket,
+                    newFileKey,
+                    constantFileContent
+                  )
+                })
+
+                it('should copy the old file to the primary with the old key', async function () {
+                  // wait for the file to copy in the background
+                  await msleep(1000)
+
+                  await TestHelper.expectPersistorToHaveFile(
+                    app.persistor.primaryPersistor,
+                    bucket,
+                    fileKey,
+                    constantFileContent
+                  )
+                })
+              })
+            })
+          })
+
+          describe('when sending a file', function () {
+            beforeEach(async function () {
+              const writeStream = request.post(fileUrl)
+              const readStream =
+                streamifier.createReadStream(constantFileContent)
+              // hack to consume the result to ensure the http request has been fully processed
+              const resultStream = fs.createWriteStream('/dev/null')
+              await pipeline(readStream, writeStream, resultStream)
+            })
+
+            it('should store the file on the primary', async function () {
+              await TestHelper.expectPersistorToHaveFile(
+                app.persistor.primaryPersistor,
+                bucket,
+                fileKey,
+                constantFileContent
+              )
+            })
+
+            it('should not store the file on the fallback', async function () {
+              await TestHelper.expectPersistorNotToHaveFile(
+                app.persistor.fallbackPersistor,
+                fallbackBucket,
+                `${projectId}/${fileId}`
+              )
+            })
+          })
+
+          describe('when deleting a file', function () {
+            describe('when the file exists on the primary', function () {
+              beforeEach(async function () {
+                await TestHelper.uploadStringToPersistor(
+                  app.persistor.primaryPersistor,
+                  bucket,
+                  fileKey,
+                  constantFileContent
+                )
+              })
+
+              it('should delete the file', async function () {
+                const response = await rp.del(fileUrl)
+                expect(response.statusCode).to.equal(204)
+                await expect(
+                  rp.get(fileUrl)
+                ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+              })
+            })
+
+            describe('when the file exists on the fallback', function () {
+              beforeEach(async function () {
+                await TestHelper.uploadStringToPersistor(
+                  app.persistor.fallbackPersistor,
+                  fallbackBucket,
+                  fileKey,
+                  constantFileContent
+                )
+              })
+
+              it('should delete the file', async function () {
+                const response = await rp.del(fileUrl)
+                expect(response.statusCode).to.equal(204)
+                await expect(
+                  rp.get(fileUrl)
+                ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+              })
+            })
+
+            describe('when the file exists on both the primary and the fallback', function () {
+              beforeEach(async function () {
+                await TestHelper.uploadStringToPersistor(
+                  app.persistor.primaryPersistor,
+                  bucket,
+                  fileKey,
+                  constantFileContent
+                )
+                await TestHelper.uploadStringToPersistor(
+                  app.persistor.fallbackPersistor,
+                  fallbackBucket,
+                  fileKey,
+                  constantFileContent
+                )
+              })
+
+              it('should delete the files', async function () {
+                const response = await rp.del(fileUrl)
+                expect(response.statusCode).to.equal(204)
+                await expect(
+                  rp.get(fileUrl)
+                ).to.eventually.be.rejected.and.have.property('statusCode', 404)
+              })
+            })
+
+            describe('when the file does not exist', function () {
+              it('should return return 204', async function () {
+                // S3 doesn't give us a 404 when the object doesn't exist, so to stay
+                // consistent we merrily return 204 ourselves here as well
+                const response = await rp.del(fileUrl)
+                expect(response.statusCode).to.equal(204)
+              })
+            })
+          })
+        })
+      }
+
+      describe('with a pdf file', function () {
+        let fileId, fileUrl, localFileSize
+        const localFileReadPath = Path.resolve(
+          __dirname,
+          '../../fixtures/test.pdf'
+        )
+
+        beforeEach(async function () {
+          fileId = ObjectId().toString()
+          fileUrl = `${filestoreUrl}/project/${projectId}/file/${fileId}`
+          const stat = await fsStat(localFileReadPath)
+          localFileSize = stat.size
+          const writeStream = request.post(fileUrl)
+          const endStream = fs.createWriteStream('/dev/null')
+          const readStream = fs.createReadStream(localFileReadPath)
+          await pipeline(readStream, writeStream, endStream)
+        })
+
+        it('should be able get the file back', async function () {
+          const response = await rp.get(fileUrl)
+          expect(response.body.substring(0, 8)).to.equal('%PDF-1.5')
+        })
+
+        if (['S3Persistor', 'GcsPersistor'].includes(backend)) {
+          it('should record an egress metric for the upload', async function () {
+            const metric = await TestHelper.getMetric(
+              filestoreUrl,
+              `${metricPrefix}_egress`
+            )
+            expect(metric - previousEgress).to.equal(localFileSize)
+          })
+        }
+
+        describe('getting the preview image', function () {
+          this.timeout(1000 * 20)
+          let previewFileUrl
+
+          beforeEach(function () {
+            previewFileUrl = `${fileUrl}?style=preview`
+          })
+
+          it('should not time out', async function () {
+            const response = await rp.get(previewFileUrl)
+            expect(response.statusCode).to.equal(200)
+          })
+
+          it('should respond with image data', async function () {
+            // note: this test relies of the imagemagick conversion working
+            const response = await rp.get(previewFileUrl)
+            expect(response.body.length).to.be.greaterThan(400)
+            expect(response.body.substr(1, 3)).to.equal('PNG')
+          })
+        })
+
+        describe('warming the cache', function () {
+          this.timeout(1000 * 20)
+          let previewFileUrl
+
+          beforeEach(function () {
+            previewFileUrl = `${fileUrl}?style=preview&cacheWarm=true`
+          })
+
+          it('should not time out', async function () {
+            const response = await rp.get(previewFileUrl)
+            expect(response.statusCode).to.equal(200)
+          })
+
+          it("should respond with only an 'OK'", async function () {
+            // note: this test relies of the imagemagick conversion working
+            const response = await rp.get(previewFileUrl)
+            expect(response.body).to.equal('OK')
+          })
+        })
+      })
+    })
+  })
+})

services/filestore/test/acceptance/js/TestConfig.js

@@ -0,0 +1,113 @@
+const Path = require('path')
+
+// use functions to get a fresh copy, not a reference, each time
+function s3Config() {
+  return {
+    key: process.env.AWS_ACCESS_KEY_ID,
+    secret: process.env.AWS_SECRET_ACCESS_KEY,
+    endpoint: process.env.AWS_S3_ENDPOINT,
+    pathStyle: true,
+    partSize: 100 * 1024 * 1024,
+  }
+}
+
+function s3Stores() {
+  return {
+    user_files: process.env.AWS_S3_USER_FILES_BUCKET_NAME,
+    template_files: process.env.AWS_S3_TEMPLATE_FILES_BUCKET_NAME,
+    public_files: process.env.AWS_S3_PUBLIC_FILES_BUCKET_NAME,
+  }
+}
+
+function gcsConfig() {
+  return {
+    endpoint: {
+      apiEndpoint: process.env.GCS_API_ENDPOINT,
+      apiScheme: process.env.GCS_API_SCHEME,
+      projectId: 'fake',
+    },
+    directoryKeyRegex: new RegExp('^[0-9a-fA-F]{24}/[0-9a-fA-F]{24}'),
+    unlockBeforeDelete: false, // fake-gcs does not support this
+    deletedBucketSuffix: '-deleted',
+  }
+}
+
+function gcsStores() {
+  return {
+    user_files: process.env.GCS_USER_FILES_BUCKET_NAME,
+    template_files: process.env.GCS_TEMPLATE_FILES_BUCKET_NAME,
+    public_files: process.env.GCS_PUBLIC_FILES_BUCKET_NAME,
+  }
+}
+
+function fsStores() {
+  return {
+    user_files: Path.resolve(__dirname, '../../../user_files'),
+    public_files: Path.resolve(__dirname, '../../../public_files'),
+    template_files: Path.resolve(__dirname, '../../../template_files'),
+  }
+}
+
+function fallbackStores(primaryConfig, fallbackConfig) {
+  return {
+    [primaryConfig.user_files]: fallbackConfig.user_files,
+    [primaryConfig.public_files]: fallbackConfig.public_files,
+    [primaryConfig.template_files]: fallbackConfig.template_files,
+  }
+}
+
+module.exports = {
+  FSPersistor: {
+    backend: 'fs',
+    stores: fsStores(),
+  },
+  S3Persistor: {
+    backend: 's3',
+    s3: s3Config(),
+    stores: s3Stores(),
+  },
+  GcsPersistor: {
+    backend: 'gcs',
+    gcs: gcsConfig(),
+    stores: gcsStores(),
+  },
+  FallbackS3ToFSPersistor: {
+    backend: 's3',
+    s3: s3Config(),
+    stores: s3Stores(),
+    fallback: {
+      backend: 'fs',
+      buckets: fallbackStores(s3Stores(), fsStores()),
+    },
+  },
+  FallbackFSToS3Persistor: {
+    backend: 'fs',
+    s3: s3Config(),
+    stores: fsStores(),
+    fallback: {
+      backend: 's3',
+      buckets: fallbackStores(fsStores(), s3Stores()),
+    },
+  },
+  FallbackGcsToS3Persistor: {
+    backend: 'gcs',
+    gcs: gcsConfig(),
+    stores: gcsStores(),
+    s3: s3Config(),
+    fallback: {
+      backend: 's3',
+      buckets: fallbackStores(gcsStores(), s3Stores()),
+    },
+  },
+  FallbackS3ToGcsPersistor: {
+    backend: 's3',
+    // can use the same bucket names for gcs and s3 (in tests)
+    stores: s3Stores(),
+    s3: s3Config(),
+    gcs: gcsConfig(),
+    fallback: {
+      backend: 'gcs',
+      buckets: fallbackStores(s3Stores(), gcsStores()),
+    },
+  },
+}

services/filestore/test/acceptance/js/TestHelper.js

@@ -0,0 +1,54 @@
+const streamifier = require('streamifier')
+const rp = require('request-promise-native').defaults({
+  resolveWithFullResponse: true,
+})
+
+const { expect } = require('chai')
+
+module.exports = {
+  uploadStringToPersistor,
+  getStringFromPersistor,
+  expectPersistorToHaveFile,
+  expectPersistorNotToHaveFile,
+  streamToString,
+  getMetric,
+}
+
+async function getMetric(filestoreUrl, metric) {
+  const res = await rp.get(`${filestoreUrl}/metrics`)
+  expect(res.statusCode).to.equal(200)
+  const metricRegex = new RegExp(`^${metric}{[^}]+} ([0-9]+)$`, 'm')
+  const found = metricRegex.exec(res.body)
+  return parseInt(found ? found[1] : 0) || 0
+}
+
+function streamToString(stream) {
+  const chunks = []
+  return new Promise((resolve, reject) => {
+    stream.on('data', chunk => chunks.push(chunk))
+    stream.on('error', reject)
+    stream.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')))
+    stream.resume()
+  })
+}
+
+async function uploadStringToPersistor(persistor, bucket, key, content) {
+  const fileStream = streamifier.createReadStream(content)
+  await persistor.sendStream(bucket, key, fileStream)
+}
+
+async function getStringFromPersistor(persistor, bucket, key) {
+  const stream = await persistor.getObjectStream(bucket, key, {})
+  return streamToString(stream)
+}
+
+async function expectPersistorToHaveFile(persistor, bucket, key, content) {
+  const foundContent = await getStringFromPersistor(persistor, bucket, key)
+  expect(foundContent).to.equal(content)
+}
+
+async function expectPersistorNotToHaveFile(persistor, bucket, key) {
+  await expect(
+    getStringFromPersistor(persistor, bucket, key)
+  ).to.eventually.have.been.rejected.with.property('name', 'NotFoundError')
+}

services/filestore/test/unit/js/FileControllerTests.js

@@ -0,0 +1,347 @@
+const sinon = require('sinon')
+const chai = require('chai')
+const { expect } = chai
+const SandboxedModule = require('sandboxed-module')
+const Errors = require('../../../app/js/Errors')
+const modulePath = '../../../app/js/FileController.js'
+
+describe('FileController', function () {
+  let PersistorManager,
+    FileHandler,
+    LocalFileWriter,
+    FileController,
+    req,
+    res,
+    next,
+    stream
+  const settings = {
+    s3: {
+      buckets: {
+        user_files: 'user_files',
+      },
+    },
+  }
+  const fileSize = 1234
+  const fileStream = 'fileStream'
+  const projectId = 'projectId'
+  const fileId = 'file_id'
+  const bucket = 'user_files'
+  const key = `${projectId}/${fileId}`
+  const error = new Error('incorrect utensil')
+
+  beforeEach(function () {
+    PersistorManager = {
+      sendStream: sinon.stub().yields(),
+      copyObject: sinon.stub().resolves(),
+      deleteObject: sinon.stub().yields(),
+    }
+
+    FileHandler = {
+      getFile: sinon.stub().yields(null, fileStream),
+      getFileSize: sinon.stub().yields(null, fileSize),
+      deleteFile: sinon.stub().yields(),
+      deleteProject: sinon.stub().yields(),
+      insertFile: sinon.stub().yields(),
+      getDirectorySize: sinon.stub().yields(null, fileSize),
+      getRedirectUrl: sinon.stub().yields(null, null),
+    }
+
+    LocalFileWriter = {}
+    stream = {
+      pipeline: sinon.stub(),
+    }
+
+    FileController = SandboxedModule.require(modulePath, {
+      requires: {
+        './LocalFileWriter': LocalFileWriter,
+        './FileHandler': FileHandler,
+        './PersistorManager': PersistorManager,
+        './Errors': Errors,
+        stream: stream,
+        '@overleaf/settings': settings,
+        '@overleaf/metrics': {
+          inc() {},
+        },
+      },
+      globals: { console },
+    })
+
+    req = {
+      key: key,
+      bucket: bucket,
+      project_id: projectId,
+      query: {},
+      params: {
+        project_id: projectId,
+        file_id: fileId,
+      },
+      headers: {},
+      requestLogger: {
+        setMessage: sinon.stub(),
+        addFields: sinon.stub(),
+      },
+    }
+
+    res = {
+      set: sinon.stub().returnsThis(),
+      sendStatus: sinon.stub().returnsThis(),
+      status: sinon.stub().returnsThis(),
+    }
+
+    next = sinon.stub()
+  })
+
+  describe('getFile', function () {
+    it('should try and get a redirect url first', function () {
+      FileController.getFile(req, res, next)
+      expect(FileHandler.getRedirectUrl).to.have.been.calledWith(bucket, key)
+    })
+
+    it('should pipe the stream', function () {
+      FileController.getFile(req, res, next)
+      expect(stream.pipeline).to.have.been.calledWith(fileStream, res)
+    })
+
+    it('should send a 200 if the cacheWarm param is true', function (done) {
+      req.query.cacheWarm = true
+      res.sendStatus = statusCode => {
+        statusCode.should.equal(200)
+        done()
+      }
+      FileController.getFile(req, res, next)
+    })
+
+    it('should send an error if there is a problem', function () {
+      FileHandler.getFile.yields(error)
+      FileController.getFile(req, res, next)
+      expect(next).to.have.been.calledWith(error)
+    })
+
+    describe('with a redirect url', function () {
+      const redirectUrl = 'https://wombat.potato/giraffe'
+
+      beforeEach(function () {
+        FileHandler.getRedirectUrl.yields(null, redirectUrl)
+        res.redirect = sinon.stub()
+      })
+
+      it('should redirect', function () {
+        FileController.getFile(req, res, next)
+        expect(res.redirect).to.have.been.calledWith(redirectUrl)
+      })
+
+      it('should not get a file stream', function () {
+        FileController.getFile(req, res, next)
+        expect(FileHandler.getFile).not.to.have.been.called
+      })
+
+      describe('when there is an error getting the redirect url', function () {
+        beforeEach(function () {
+          FileHandler.getRedirectUrl.yields(new Error('wombat herding error'))
+        })
+
+        it('should not redirect', function () {
+          FileController.getFile(req, res, next)
+          expect(res.redirect).not.to.have.been.called
+        })
+
+        it('should not return an error', function () {
+          FileController.getFile(req, res, next)
+          expect(next).not.to.have.been.called
+        })
+
+        it('should proxy the file', function () {
+          FileController.getFile(req, res, next)
+          expect(FileHandler.getFile).to.have.been.calledWith(bucket, key)
+        })
+      })
+    })
+
+    describe('with a range header', function () {
+      let expectedOptions
+
+      beforeEach(function () {
+        expectedOptions = {
+          bucket,
+          key,
+          format: undefined,
+          style: undefined,
+        }
+      })
+
+      it('should pass range options to FileHandler', function () {
+        req.headers.range = 'bytes=0-8'
+        expectedOptions.start = 0
+        expectedOptions.end = 8
+
+        FileController.getFile(req, res, next)
+        expect(FileHandler.getFile).to.have.been.calledWith(
+          bucket,
+          key,
+          expectedOptions
+        )
+      })
+
+      it('should ignore an invalid range header', function () {
+        req.headers.range = 'potato'
+        FileController.getFile(req, res, next)
+        expect(FileHandler.getFile).to.have.been.calledWith(
+          bucket,
+          key,
+          expectedOptions
+        )
+      })
+
+      it("should ignore any type other than 'bytes'", function () {
+        req.headers.range = 'wombats=0-8'
+        FileController.getFile(req, res, next)
+        expect(FileHandler.getFile).to.have.been.calledWith(
+          bucket,
+          key,
+          expectedOptions
+        )
+      })
+    })
+  })
+
+  describe('getFileHead', function () {
+    it('should return the file size in a Content-Length header', function (done) {
+      res.end = () => {
+        expect(res.status).to.have.been.calledWith(200)
+        expect(res.set).to.have.been.calledWith('Content-Length', fileSize)
+        done()
+      }
+
+      FileController.getFileHead(req, res, next)
+    })
+
+    it('should return a 404 is the file is not found', function (done) {
+      FileHandler.getFileSize.yields(
+        new Errors.NotFoundError({ message: 'not found', info: {} })
+      )
+
+      res.sendStatus = code => {
+        expect(code).to.equal(404)
+        done()
+      }
+
+      FileController.getFileHead(req, res, next)
+    })
+
+    it('should send an error on internal errors', function () {
+      FileHandler.getFileSize.yields(error)
+
+      FileController.getFileHead(req, res, next)
+      expect(next).to.have.been.calledWith(error)
+    })
+  })
+
+  describe('insertFile', function () {
+    it('should send bucket name key and res to PersistorManager', function (done) {
+      res.sendStatus = code => {
+        expect(FileHandler.insertFile).to.have.been.calledWith(bucket, key, req)
+        expect(code).to.equal(200)
+        done()
+      }
+      FileController.insertFile(req, res, next)
+    })
+  })
+
+  describe('copyFile', function () {
+    const oldFileId = 'oldFileId'
+    const oldProjectId = 'oldProjectid'
+    const oldKey = `${oldProjectId}/${oldFileId}`
+
+    beforeEach(function () {
+      req.body = {
+        source: {
+          project_id: oldProjectId,
+          file_id: oldFileId,
+        },
+      }
+    })
+
+    it('should send bucket name and both keys to PersistorManager', function (done) {
+      res.sendStatus = code => {
+        code.should.equal(200)
+        expect(PersistorManager.copyObject).to.have.been.calledWith(
+          bucket,
+          oldKey,
+          key
+        )
+        done()
+      }
+      FileController.copyFile(req, res, next)
+    })
+
+    it('should send a 404 if the original file was not found', function (done) {
+      PersistorManager.copyObject.rejects(
+        new Errors.NotFoundError({ message: 'not found', info: {} })
+      )
+      res.sendStatus = code => {
+        code.should.equal(404)
+        done()
+      }
+      FileController.copyFile(req, res, next)
+    })
+
+    it('should send an error if there was an error', function (done) {
+      PersistorManager.copyObject.rejects(error)
+      FileController.copyFile(req, res, err => {
+        expect(err).to.equal(error)
+        done()
+      })
+    })
+  })
+
+  describe('delete file', function () {
+    it('should tell the file handler', function (done) {
+      res.sendStatus = code => {
+        code.should.equal(204)
+        expect(FileHandler.deleteFile).to.have.been.calledWith(bucket, key)
+        done()
+      }
+      FileController.deleteFile(req, res, next)
+    })
+
+    it('should send a 500 if there was an error', function () {
+      FileHandler.deleteFile.yields(error)
+      FileController.deleteFile(req, res, next)
+      expect(next).to.have.been.calledWith(error)
+    })
+  })
+
+  describe('delete project', function () {
+    it('should tell the file handler', function (done) {
+      res.sendStatus = code => {
+        code.should.equal(204)
+        expect(FileHandler.deleteProject).to.have.been.calledWith(bucket, key)
+        done()
+      }
+      FileController.deleteProject(req, res, next)
+    })
+
+    it('should send a 500 if there was an error', function () {
+      FileHandler.deleteProject.yields(error)
+      FileController.deleteProject(req, res, next)
+      expect(next).to.have.been.calledWith(error)
+    })
+  })
+
+  describe('directorySize', function () {
+    it('should return total directory size bytes', function (done) {
+      FileController.directorySize(req, {
+        json: result => {
+          expect(result['total bytes']).to.equal(fileSize)
+          done()
+        },
+      })
+    })
+
+    it('should send a 500 if there was an error', function () {
+      FileHandler.getDirectorySize.yields(error)
+      FileController.directorySize(req, res, next)
+      expect(next).to.have.been.calledWith(error)
+    })
+  })
+})

services/filestore/test/unit/js/FileConverterTests.js

@@ -0,0 +1,107 @@
+const sinon = require('sinon')
+const chai = require('chai')
+const { expect } = chai
+const SandboxedModule = require('sandboxed-module')
+const { Errors } = require('@overleaf/object-persistor')
+
+const modulePath = '../../../app/js/FileConverter.js'
+
+describe('FileConverter', function () {
+  let SafeExec, FileConverter
+  const sourcePath = '/data/wombat.eps'
+  const destPath = '/tmp/dest.png'
+  const format = 'png'
+  const errorMessage = 'guru meditation error'
+  const Settings = {
+    commands: {
+      convertCommandPrefix: [],
+    },
+  }
+
+  beforeEach(function () {
+    SafeExec = {
+      promises: sinon.stub().resolves(destPath),
+    }
+
+    const ObjectPersistor = { Errors }
+
+    FileConverter = SandboxedModule.require(modulePath, {
+      requires: {
+        './SafeExec': SafeExec,
+        '@overleaf/metrics': {
+          inc: sinon.stub(),
+          Timer: sinon.stub().returns({ done: sinon.stub() }),
+        },
+        '@overleaf/settings': Settings,
+        '@overleaf/object-persistor': ObjectPersistor,
+      },
+    })
+  })
+
+  describe('convert', function () {
+    it('should convert the source to the requested format', async function () {
+      await FileConverter.promises.convert(sourcePath, format)
+      const args = SafeExec.promises.args[0][0]
+      expect(args).to.include(`${sourcePath}[0]`)
+      expect(args).to.include(`${sourcePath}.${format}`)
+    })
+
+    it('should return the dest path', async function () {
+      const destPath = await FileConverter.promises.convert(sourcePath, format)
+      destPath.should.equal(`${sourcePath}.${format}`)
+    })
+
+    it('should wrap the error from convert', async function () {
+      SafeExec.promises.rejects(errorMessage)
+      try {
+        await FileConverter.promises.convert(sourcePath, format)
+        expect('error should have been thrown').not.to.exist
+      } catch (err) {
+        expect(err.name).to.equal('ConversionError')
+        expect(err.cause.toString()).to.equal(errorMessage)
+      }
+    })
+
+    it('should not accept an non approved format', async function () {
+      try {
+        await FileConverter.promises.convert(sourcePath, 'potato')
+        expect('error should have been thrown').not.to.exist
+      } catch (err) {
+        expect(err.name).to.equal('ConversionError')
+      }
+    })
+
+    it('should prefix the command with Settings.commands.convertCommandPrefix', async function () {
+      Settings.commands.convertCommandPrefix = ['nice']
+      await FileConverter.promises.convert(sourcePath, format)
+    })
+
+    it('should convert the file when called as a callback', function (done) {
+      FileConverter.convert(sourcePath, format, (err, destPath) => {
+        expect(err).not.to.exist
+        destPath.should.equal(`${sourcePath}.${format}`)
+
+        const args = SafeExec.promises.args[0][0]
+        expect(args).to.include(`${sourcePath}[0]`)
+        expect(args).to.include(`${sourcePath}.${format}`)
+        done()
+      })
+    })
+  })
+
+  describe('thumbnail', function () {
+    it('should call converter resize with args', async function () {
+      await FileConverter.promises.thumbnail(sourcePath)
+      const args = SafeExec.promises.args[0][0]
+      expect(args).to.include(`${sourcePath}[0]`)
+    })
+  })
+
+  describe('preview', function () {
+    it('should call converter resize with args', async function () {
+      await FileConverter.promises.preview(sourcePath)
+      const args = SafeExec.promises.args[0][0]
+      expect(args).to.include(`${sourcePath}[0]`)
+    })
+  })
+})

services/filestore/test/unit/js/FileHandlerTests.js

@@ -0,0 +1,398 @@
+const sinon = require('sinon')
+const chai = require('chai')
+const { expect } = chai
+const modulePath = '../../../app/js/FileHandler.js'
+const SandboxedModule = require('sandboxed-module')
+const { ObjectId } = require('mongodb')
+const { Errors } = require('@overleaf/object-persistor')
+
+chai.use(require('sinon-chai'))
+chai.use(require('chai-as-promised'))
+
+describe('FileHandler', function () {
+  let PersistorManager,
+    LocalFileWriter,
+    FileConverter,
+    KeyBuilder,
+    ImageOptimiser,
+    FileHandler,
+    Settings,
+    fs
+
+  const bucket = 'my_bucket'
+  const key = `${ObjectId()}/${ObjectId()}`
+  const convertedFolderKey = `${ObjectId()}/${ObjectId()}`
+  const projectKey = `${ObjectId()}/`
+  const sourceStream = 'sourceStream'
+  const convertedKey = 'convertedKey'
+  const redirectUrl = 'https://wombat.potato/giraffe'
+  const readStream = {
+    stream: 'readStream',
+    on: sinon.stub(),
+  }
+
+  beforeEach(function () {
+    PersistorManager = {
+      getObjectStream: sinon.stub().resolves(sourceStream),
+      getRedirectUrl: sinon.stub().resolves(redirectUrl),
+      checkIfObjectExists: sinon.stub().resolves(),
+      deleteObject: sinon.stub().resolves(),
+      deleteDirectory: sinon.stub().resolves(),
+      sendStream: sinon.stub().resolves(),
+      insertFile: sinon.stub().resolves(),
+      sendFile: sinon.stub().resolves(),
+      directorySize: sinon.stub().resolves(),
+    }
+    LocalFileWriter = {
+      // the callback style is used for detached cleanup calls
+      deleteFile: sinon.stub().yields(),
+      promises: {
+        writeStream: sinon.stub().resolves(),
+        deleteFile: sinon.stub().resolves(),
+      },
+    }
+    FileConverter = {
+      promises: {
+        convert: sinon.stub().resolves(),
+        thumbnail: sinon.stub().resolves(),
+        preview: sinon.stub().resolves(),
+      },
+    }
+    KeyBuilder = {
+      addCachingToKey: sinon.stub().returns(convertedKey),
+      getConvertedFolderKey: sinon.stub().returns(convertedFolderKey),
+    }
+    ImageOptimiser = {
+      promises: {
+        compressPng: sinon.stub().resolves(),
+      },
+    }
+    Settings = {}
+    fs = {
+      createReadStream: sinon.stub().returns(readStream),
+    }
+
+    const ObjectPersistor = { Errors }
+
+    FileHandler = SandboxedModule.require(modulePath, {
+      requires: {
+        './PersistorManager': PersistorManager,
+        './LocalFileWriter': LocalFileWriter,
+        './FileConverter': FileConverter,
+        './KeyBuilder': KeyBuilder,
+        './ImageOptimiser': ImageOptimiser,
+        '@overleaf/settings': Settings,
+        '@overleaf/object-persistor': ObjectPersistor,
+        fs: fs,
+      },
+      globals: { console },
+    })
+  })
+
+  describe('insertFile', function () {
+    const stream = 'stream'
+
+    it('should send file to the filestore', function (done) {
+      FileHandler.insertFile(bucket, key, stream, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.sendStream).to.have.been.calledWith(
+          bucket,
+          key,
+          stream
+        )
+        done()
+      })
+    })
+
+    it('should not make a delete request for the convertedKey folder', function (done) {
+      FileHandler.insertFile(bucket, key, stream, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.deleteDirectory).not.to.have.been.called
+        done()
+      })
+    })
+
+    it('should accept templates-api key format', function (done) {
+      KeyBuilder.getConvertedFolderKey.returns(
+        '5ecba29f1a294e007d0bccb4/v/0/pdf'
+      )
+      FileHandler.insertFile(bucket, key, stream, err => {
+        expect(err).not.to.exist
+        done()
+      })
+    })
+
+    it('should throw an error when the key is in the wrong format', function (done) {
+      KeyBuilder.getConvertedFolderKey.returns('wombat')
+      FileHandler.insertFile(bucket, key, stream, err => {
+        expect(err).to.exist
+        done()
+      })
+    })
+
+    describe('when conversions are enabled', function () {
+      beforeEach(function () {
+        Settings.enableConversions = true
+      })
+
+      it('should delete the convertedKey folder', function (done) {
+        FileHandler.insertFile(bucket, key, stream, err => {
+          expect(err).not.to.exist
+          expect(PersistorManager.deleteDirectory).to.have.been.calledWith(
+            bucket,
+            convertedFolderKey
+          )
+          done()
+        })
+      })
+    })
+  })
+
+  describe('deleteFile', function () {
+    it('should tell the filestore manager to delete the file', function (done) {
+      FileHandler.deleteFile(bucket, key, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.deleteObject).to.have.been.calledWith(
+          bucket,
+          key
+        )
+        done()
+      })
+    })
+
+    it('should not tell the filestore manager to delete the cached folder', function (done) {
+      FileHandler.deleteFile(bucket, key, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.deleteDirectory).not.to.have.been.called
+        done()
+      })
+    })
+
+    it('should accept templates-api key format', function (done) {
+      KeyBuilder.getConvertedFolderKey.returns(
+        '5ecba29f1a294e007d0bccb4/v/0/pdf'
+      )
+      FileHandler.deleteFile(bucket, key, err => {
+        expect(err).not.to.exist
+        done()
+      })
+    })
+
+    it('should throw an error when the key is in the wrong format', function (done) {
+      KeyBuilder.getConvertedFolderKey.returns('wombat')
+      FileHandler.deleteFile(bucket, key, err => {
+        expect(err).to.exist
+        done()
+      })
+    })
+
+    describe('when conversions are enabled', function () {
+      beforeEach(function () {
+        Settings.enableConversions = true
+      })
+
+      it('should delete the convertedKey folder', function (done) {
+        FileHandler.deleteFile(bucket, key, err => {
+          expect(err).not.to.exist
+          expect(PersistorManager.deleteDirectory).to.have.been.calledWith(
+            bucket,
+            convertedFolderKey
+          )
+          done()
+        })
+      })
+    })
+  })
+
+  describe('deleteProject', function () {
+    it('should tell the filestore manager to delete the folder', function (done) {
+      FileHandler.deleteProject(bucket, projectKey, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.deleteDirectory).to.have.been.calledWith(
+          bucket,
+          projectKey
+        )
+        done()
+      })
+    })
+
+    it('should throw an error when the key is in the wrong format', function (done) {
+      FileHandler.deleteProject(bucket, 'wombat', err => {
+        expect(err).to.exist
+        done()
+      })
+    })
+  })
+
+  describe('getFile', function () {
+    it('should return the source stream no format or style are defined', function (done) {
+      FileHandler.getFile(bucket, key, null, (err, stream) => {
+        expect(err).not.to.exist
+        expect(stream).to.equal(sourceStream)
+        done()
+      })
+    })
+
+    it('should pass options through to PersistorManager', function (done) {
+      const options = { start: 0, end: 8 }
+      FileHandler.getFile(bucket, key, options, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.getObjectStream).to.have.been.calledWith(
+          bucket,
+          key,
+          options
+        )
+        done()
+      })
+    })
+
+    describe('when a format is defined', function () {
+      let result
+
+      describe('when the file is not cached', function () {
+        beforeEach(function (done) {
+          FileHandler.getFile(bucket, key, { format: 'png' }, (err, stream) => {
+            result = { err, stream }
+            done()
+          })
+        })
+
+        it('should convert the file', function () {
+          expect(FileConverter.promises.convert).to.have.been.called
+        })
+
+        it('should compress the converted file', function () {
+          expect(ImageOptimiser.promises.compressPng).to.have.been.called
+        })
+
+        it('should return the the converted stream', function () {
+          expect(result.err).not.to.exist
+          expect(result.stream).to.equal(readStream)
+          expect(PersistorManager.getObjectStream).to.have.been.calledWith(
+            bucket,
+            key
+          )
+        })
+      })
+
+      describe('when the file is cached', function () {
+        beforeEach(function (done) {
+          PersistorManager.checkIfObjectExists = sinon.stub().resolves(true)
+          FileHandler.getFile(bucket, key, { format: 'png' }, (err, stream) => {
+            result = { err, stream }
+            done()
+          })
+        })
+
+        it('should not convert the file', function () {
+          expect(FileConverter.promises.convert).not.to.have.been.called
+        })
+
+        it('should not compress the converted file again', function () {
+          expect(ImageOptimiser.promises.compressPng).not.to.have.been.called
+        })
+
+        it('should return the cached stream', function () {
+          expect(result.err).not.to.exist
+          expect(result.stream).to.equal(sourceStream)
+          expect(PersistorManager.getObjectStream).to.have.been.calledWith(
+            bucket,
+            convertedKey
+          )
+        })
+      })
+    })
+
+    describe('when a style is defined', function () {
+      it('generates a thumbnail when requested', function (done) {
+        FileHandler.getFile(bucket, key, { style: 'thumbnail' }, err => {
+          expect(err).not.to.exist
+          expect(FileConverter.promises.thumbnail).to.have.been.called
+          expect(FileConverter.promises.preview).not.to.have.been.called
+          done()
+        })
+      })
+
+      it('generates a preview when requested', function (done) {
+        FileHandler.getFile(bucket, key, { style: 'preview' }, err => {
+          expect(err).not.to.exist
+          expect(FileConverter.promises.thumbnail).not.to.have.been.called
+          expect(FileConverter.promises.preview).to.have.been.called
+          done()
+        })
+      })
+    })
+  })
+
+  describe('getRedirectUrl', function () {
+    beforeEach(function () {
+      Settings.filestore = {
+        allowRedirects: true,
+        stores: {
+          userFiles: bucket,
+        },
+      }
+    })
+
+    it('should return a redirect url', function (done) {
+      FileHandler.getRedirectUrl(bucket, key, (err, url) => {
+        expect(err).not.to.exist
+        expect(url).to.equal(redirectUrl)
+        done()
+      })
+    })
+
+    it('should call the persistor to get a redirect url', function (done) {
+      FileHandler.getRedirectUrl(bucket, key, () => {
+        expect(PersistorManager.getRedirectUrl).to.have.been.calledWith(
+          bucket,
+          key
+        )
+        done()
+      })
+    })
+
+    it('should return null if options are supplied', function (done) {
+      FileHandler.getRedirectUrl(
+        bucket,
+        key,
+        { start: 100, end: 200 },
+        (err, url) => {
+          expect(err).not.to.exist
+          expect(url).to.be.null
+          done()
+        }
+      )
+    })
+
+    it('should return null if the bucket is not one of the defined ones', function (done) {
+      FileHandler.getRedirectUrl('a_different_bucket', key, (err, url) => {
+        expect(err).not.to.exist
+        expect(url).to.be.null
+        done()
+      })
+    })
+
+    it('should return null if redirects are not enabled', function (done) {
+      Settings.filestore.allowRedirects = false
+      FileHandler.getRedirectUrl(bucket, key, (err, url) => {
+        expect(err).not.to.exist
+        expect(url).to.be.null
+        done()
+      })
+    })
+  })
+
+  describe('getDirectorySize', function () {
+    it('should call the filestore manager to get directory size', function (done) {
+      FileHandler.getDirectorySize(bucket, key, err => {
+        expect(err).not.to.exist
+        expect(PersistorManager.directorySize).to.have.been.calledWith(
+          bucket,
+          key
+        )
+        done()
+      })
+    })
+  })
+})

services/filestore/test/unit/js/ImageOptimiserTests.js

@@ -0,0 +1,71 @@
+const sinon = require('sinon')
+const chai = require('chai')
+const { expect } = chai
+const modulePath = '../../../app/js/ImageOptimiser.js'
+const { FailedCommandError } = require('../../../app/js/Errors')
+const SandboxedModule = require('sandboxed-module')
+
+describe('ImageOptimiser', function () {
+  let ImageOptimiser, SafeExec, logger
+  const sourcePath = '/wombat/potato.eps'
+
+  beforeEach(function () {
+    SafeExec = {
+      promises: sinon.stub().resolves(),
+    }
+    logger = {
+      warn: sinon.stub(),
+    }
+    ImageOptimiser = SandboxedModule.require(modulePath, {
+      requires: {
+        './SafeExec': SafeExec,
+        'logger-sharelatex': logger,
+        '@overleaf/metrics': {
+          Timer: sinon.stub().returns({ done: sinon.stub() }),
+        },
+      },
+    })
+  })
+
+  describe('compressPng', function () {
+    it('should convert the file', function (done) {
+      ImageOptimiser.compressPng(sourcePath, err => {
+        expect(err).not.to.exist
+        expect(SafeExec.promises).to.have.been.calledWith([
+          'optipng',
+          sourcePath,
+        ])
+        done()
+      })
+    })
+
+    it('should return the error', function (done) {
+      SafeExec.promises.rejects('wombat herding failure')
+      ImageOptimiser.compressPng(sourcePath, err => {
+        expect(err.toString()).to.equal('wombat herding failure')
+        done()
+      })
+    })
+  })
+
+  describe('when optimiser is sigkilled', function () {
+    const expectedError = new FailedCommandError('', 'SIGKILL', '', '')
+    let error
+
+    beforeEach(function (done) {
+      SafeExec.promises.rejects(expectedError)
+      ImageOptimiser.compressPng(sourcePath, err => {
+        error = err
+        done()
+      })
+    })
+
+    it('should not produce an error', function () {
+      expect(error).not.to.exist
+    })
+
+    it('should log a warning', function () {
+      expect(logger.warn).to.have.been.calledOnce
+    })
+  })
+})

services/filestore/test/unit/js/KeybuilderTests.js

@@ -0,0 +1,37 @@
+const SandboxedModule = require('sandboxed-module')
+
+const modulePath = '../../../app/js/KeyBuilder.js'
+
+describe('KeybuilderTests', function () {
+  let KeyBuilder
+  const key = 'wombat/potato'
+
+  beforeEach(function () {
+    KeyBuilder = SandboxedModule.require(modulePath, {
+      requires: { '@overleaf/settings': {} },
+    })
+  })
+
+  describe('cachedKey', function () {
+    it('should add the format to the key', function () {
+      const opts = { format: 'png' }
+      const newKey = KeyBuilder.addCachingToKey(key, opts)
+      newKey.should.equal(`${key}-converted-cache/format-png`)
+    })
+
+    it('should add the style to the key', function () {
+      const opts = { style: 'thumbnail' }
+      const newKey = KeyBuilder.addCachingToKey(key, opts)
+      newKey.should.equal(`${key}-converted-cache/style-thumbnail`)
+    })
+
+    it('should add format first, then style', function () {
+      const opts = {
+        style: 'thumbnail',
+        format: 'png',
+      }
+      const newKey = KeyBuilder.addCachingToKey(key, opts)
+      newKey.should.equal(`${key}-converted-cache/format-png-style-thumbnail`)
+    })
+  })
+})

services/filestore/test/unit/js/LocalFileWriterTests.js

@@ -0,0 +1,111 @@
+const sinon = require('sinon')
+const chai = require('chai')
+const { expect } = chai
+const modulePath = '../../../app/js/LocalFileWriter.js'
+const SandboxedModule = require('sandboxed-module')
+const { Errors } = require('@overleaf/object-persistor')
+chai.use(require('sinon-chai'))
+
+describe('LocalFileWriter', function () {
+  const writeStream = 'writeStream'
+  const readStream = 'readStream'
+  const settings = { path: { uploadFolder: '/uploads' } }
+  const fsPath = '/uploads/wombat'
+  const filename = 'wombat'
+  let stream, fs, LocalFileWriter
+
+  beforeEach(function () {
+    fs = {
+      createWriteStream: sinon.stub().returns(writeStream),
+      unlink: sinon.stub().yields(),
+    }
+    stream = {
+      pipeline: sinon.stub().yields(),
+    }
+
+    const ObjectPersistor = { Errors }
+
+    LocalFileWriter = SandboxedModule.require(modulePath, {
+      requires: {
+        fs,
+        stream,
+        '@overleaf/settings': settings,
+        '@overleaf/metrics': {
+          inc: sinon.stub(),
+          Timer: sinon.stub().returns({ done: sinon.stub() }),
+        },
+        '@overleaf/object-persistor': ObjectPersistor,
+      },
+    })
+  })
+
+  describe('writeStream', function () {
+    it('writes the stream to the upload folder', function (done) {
+      LocalFileWriter.writeStream(readStream, filename, (err, path) => {
+        expect(err).not.to.exist
+        expect(fs.createWriteStream).to.have.been.calledWith(fsPath)
+        expect(stream.pipeline).to.have.been.calledWith(readStream, writeStream)
+        expect(path).to.equal(fsPath)
+        done()
+      })
+    })
+
+    describe('when there is an error', function () {
+      const error = new Error('not enough ketchup')
+      beforeEach(function () {
+        stream.pipeline.yields(error)
+      })
+
+      it('should wrap the error', function () {
+        LocalFileWriter.writeStream(readStream, filename, err => {
+          expect(err).to.exist
+          expect(err.cause).to.equal(error)
+        })
+      })
+
+      it('should delete the temporary file', function () {
+        LocalFileWriter.writeStream(readStream, filename, () => {
+          expect(fs.unlink).to.have.been.calledWith(fsPath)
+        })
+      })
+    })
+  })
+
+  describe('deleteFile', function () {
+    it('should unlink the file', function (done) {
+      LocalFileWriter.deleteFile(fsPath, err => {
+        expect(err).not.to.exist
+        expect(fs.unlink).to.have.been.calledWith(fsPath)
+        done()
+      })
+    })
+
+    it('should not call unlink with an empty path', function (done) {
+      LocalFileWriter.deleteFile('', err => {
+        expect(err).not.to.exist
+        expect(fs.unlink).not.to.have.been.called
+        done()
+      })
+    })
+
+    it('should not throw a error if the file does not exist', function (done) {
+      const error = new Error('file not found')
+      error.code = 'ENOENT'
+      fs.unlink = sinon.stub().yields(error)
+      LocalFileWriter.deleteFile(fsPath, err => {
+        expect(err).not.to.exist
+        done()
+      })
+    })
+
+    it('should wrap the error', function (done) {
+      const error = new Error('failed to reticulate splines')
+      fs.unlink = sinon.stub().yields(error)
+      LocalFileWriter.deleteFile(fsPath, err => {
+        expect(err).to.exist
+        expect(err.cause).to.equal(error)
+        done()
+      })
+    })
+  })
+})

services/filestore/test/unit/js/SafeExecTests.js

@@ -0,0 +1,110 @@
+const chai = require('chai')
+const should = chai.should()
+const { expect } = chai
+const modulePath = '../../../app/js/SafeExec'
+const { Errors } = require('@overleaf/object-persistor')
+const SandboxedModule = require('sandboxed-module')
+
+describe('SafeExec', function () {
+  let settings, options, safeExec
+
+  beforeEach(function () {
+    settings = { enableConversions: true }
+    options = { timeout: 10 * 1000, killSignal: 'SIGTERM' }
+
+    const ObjectPersistor = { Errors }
+
+    safeExec = SandboxedModule.require(modulePath, {
+      globals: { process },
+      requires: {
+        '@overleaf/settings': settings,
+        '@overleaf/object-persistor': ObjectPersistor,
+      },
+    })
+  })
+
+  describe('safeExec', function () {
+    it('should execute a valid command', function (done) {
+      safeExec(['/bin/echo', 'hello'], options, (err, stdout, stderr) => {
+        stdout.should.equal('hello\n')
+        stderr.should.equal('')
+        should.not.exist(err)
+        done()
+      })
+    })
+
+    it('should error when conversions are disabled', function (done) {
+      settings.enableConversions = false
+      safeExec(['/bin/echo', 'hello'], options, err => {
+        expect(err).to.exist
+        done()
+      })
+    })
+
+    it('should execute a command with non-zero exit status', function (done) {
+      safeExec(['/usr/bin/env', 'false'], options, err => {
+        expect(err).to.exist
+        expect(err.name).to.equal('FailedCommandError')
+        expect(err.code).to.equal(1)
+        expect(err.stdout).to.equal('')
+        expect(err.stderr).to.equal('')
+        done()
+      })
+    })
+
+    it('should handle an invalid command', function (done) {
+      safeExec(['/bin/foobar'], options, err => {
+        err.code.should.equal('ENOENT')
+        done()
+      })
+    })
+
+    it('should handle a command that runs too long', function (done) {
+      safeExec(
+        ['/bin/sleep', '10'],
+        { timeout: 500, killSignal: 'SIGTERM' },
+        err => {
+          expect(err).to.exist
+          expect(err.name).to.equal('FailedCommandError')
+          expect(err.code).to.equal('SIGTERM')
+          done()
+        }
+      )
+    })
+  })
+
+  describe('as a promise', function () {
+    beforeEach(function () {
+      safeExec = safeExec.promises
+    })
+
+    it('should execute a valid command', async function () {
+      const { stdout, stderr } = await safeExec(['/bin/echo', 'hello'], options)
+
+      stdout.should.equal('hello\n')
+      stderr.should.equal('')
+    })
+
+    it('should throw a ConversionsDisabledError when appropriate', async function () {
+      settings.enableConversions = false
+      try {
+        await safeExec(['/bin/echo', 'hello'], options)
+      } catch (err) {
+        expect(err.name).to.equal('ConversionsDisabledError')
+        return
+      }
+      expect('method did not throw an error').not.to.exist
+    })
+
+    it('should throw a FailedCommandError when appropriate', async function () {
+      try {
+        await safeExec(['/usr/bin/env', 'false'], options)
+      } catch (err) {
+        expect(err.name).to.equal('FailedCommandError')
+        expect(err.code).to.equal(1)
+        return
+      }
+      expect('method did not throw an error').not.to.exist
+    })
+  })
+})

services/filestore/test/unit/js/SettingsTests.js

@@ -0,0 +1,21 @@
+const chai = require('chai')
+const { expect } = chai
+const SandboxedModule = require('sandboxed-module')
+
+describe('Settings', function () {
+  describe('s3', function () {
+    it('should use JSONified env var if present', function () {
+      const s3Settings = {
+        bucket1: {
+          auth_key: 'bucket1_key',
+          auth_secret: 'bucket1_secret',
+        },
+      }
+      process.env.S3_BUCKET_CREDENTIALS = JSON.stringify(s3Settings)
+      const settings = SandboxedModule.require('@overleaf/settings', {
+        globals: { console, process },
+      })
+      expect(settings.filestore.s3.bucketCreds).to.deep.equal(s3Settings)
+    })
+  })
+})

services/filestore/tiny.pdf

@@ -0,0 +1,58 @@
+%PDF-1.1
+%¥±ë
+
+1 0 obj
+  << /Type /Catalog
+     /Pages 2 0 R
+  >>
+endobj
+
+2 0 obj
+  << /Type /Pages
+     /Kids [3 0 R]
+     /Count 1
+     /MediaBox [0 0 300 144]
+  >>
+endobj
+
+3 0 obj
+  <<  /Type /Page
+      /Parent 2 0 R
+      /Resources
+       << /Font
+           << /F1
+               << /Type /Font
+                  /Subtype /Type1
+                  /BaseFont /Times-Roman
+               >>
+           >>
+       >>
+      /Contents 4 0 R
+  >>
+endobj
+
+4 0 obj
+  << /Length 55 >>
+stream
+  BT
+    /F1 18 Tf
+    0 0 Td
+    (Hello World) Tj
+  ET
+endstream
+endobj
+
+xref
+0 5
+0000000000 65535 f 
+0000000018 00000 n 
+0000000077 00000 n 
+0000000178 00000 n 
+0000000457 00000 n 
+trailer
+  <<  /Root 1 0 R
+      /Size 5
+  >>
+startxref
+565
+%%EOF