feat(packages): add commons package

This is an import of 166ca8da12
with some changes to make it fit into the mono repo.
- TypedEventEmitter has been replaced with EventEmitter2 because EventEmitter2 is faster and TypedEventEmitter had some troubles with the new way of compiling.
- tsc-esm has been replaced with microbundle. The problems that lib0 doesn't export its types correctly has been solved using yarn patch.

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

.github/actions/setup-node/action.yml

@@ -36,3 +36,8 @@ runs:
       run: yarn install --immutable
       working-directory: .
       shell: bash
+
+    - name: Build commons lib
+      run: yarn build
+      working-directory: commons
+      shell: bash

.github/workflows/backend-docker.yml

@@ -39,6 +39,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'backend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/backend-e2e-tests.yml

@@ -40,6 +40,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'backend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/backend-tests.yml

@@ -41,6 +41,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'backend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/commons-lint.yml

@@ -0,0 +1,60 @@
+# SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+#
+# SPDX-License-Identifier: AGPL-3.0-only
+
+name: Commons / Lint
+
+on:
+  push:
+    branches: [ develop ]
+  pull_request:
+    branches: [ develop ]
+
+env:
+  NODE_VERSION: 18
+
+defaults:
+  run:
+    working-directory: commons
+
+jobs:
+  changes:
+    name: Check for commons changes
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: read
+    outputs:
+      changed: ${{ github.event_name == 'push' || steps.changed.outputs.files }}
+    steps:
+      - uses: actions/checkout@v3
+        if: github.event_name != 'push'
+
+      - name: Check for frontend file changes
+        if: github.event_name != 'push'
+        uses: dorny/paths-filter@v2
+        id: changed
+        with:
+          filters: |
+            files:
+              - 'commons/**'
+              - '.github/**'
+              - '.yarn/**'
+
+  lint:
+    needs: changes
+    runs-on: ubuntu-latest
+    name: Lints all .ts and .tsx files
+    steps:
+      - name: Checkout repository
+        if: needs.changes.outputs.changed == 'true'
+        uses: actions/checkout@v3
+
+      - name: Setup node
+        if: needs.changes.outputs.changed == 'true'
+        uses: ./.github/actions/setup-node
+        with:
+          NODE_VERSION: ${{ env.NODE_VERSION }}
+
+      - name: Lint code
+        if: needs.changes.outputs.changed == 'true'
+        run: yarn lint

.github/workflows/commons-tests.yml

@@ -0,0 +1,68 @@
+# SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+#
+# SPDX-License-Identifier: AGPL-3.0-only
+
+name: Commons / Run unit tests & build
+
+on:
+  push:
+    branches: [ develop ]
+  pull_request:
+    branches: [ develop ]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.job }}
+  cancel-in-progress: true
+
+defaults:
+  run:
+    working-directory: commons
+
+jobs:
+  changes:
+    name: Check for commons changes
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: read
+    outputs:
+      changed: ${{ github.event_name == 'push' || steps.changed.outputs.files }}
+    steps:
+      - uses: actions/checkout@v3
+        if: github.event_name != 'push'
+
+      - name: Check for frontend file changes
+        if: github.event_name != 'push'
+        uses: dorny/paths-filter@v2
+        id: changed
+        with:
+          filters: |
+            files:
+              - 'commons/**'
+              - '.github/**'
+              - '.yarn/**'
+
+  build:
+    needs: changes
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node: [ '14', '16', '18' ]
+    name: Test and build with NodeJS ${{ matrix.node }}
+    steps:
+      - name: Checkout repository
+        if: needs.changes.outputs.changed == 'true'
+        uses: actions/checkout@v3
+
+      - name: Setup node
+        if: needs.changes.outputs.changed == 'true'
+        uses: ./.github/actions/setup-node
+        with:
+          NODE_VERSION: ${{ matrix.node }}
+
+      - name: Test Project
+        if: needs.changes.outputs.changed == 'true'
+        run: yarn test
+
+      - name: Build project
+        if: needs.changes.outputs.changed == 'true'
+        run: yarn build

.github/workflows/frontend-docker.yml

@@ -35,6 +35,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/frontend-e2e-tests.yml

@@ -46,6 +46,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/frontend-lint.yml

@@ -36,6 +36,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/frontend-netlify-deploy-main.yml

@@ -39,6 +39,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/frontend-netlify-deploy-pr.yml

@@ -57,6 +57,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.github/workflows/frontend-test-and-build.yml

@@ -37,6 +37,7 @@ jobs:
         with:
           filters: |
             files:
+              - 'commons/**'
               - 'frontend/**'
               - '.github/**'
               - '.yarn/**'

.yarn/patches/lib0-npm-0.2.58-7de44657f5.patch

@@ -0,0 +1,366 @@
+diff --git a/package.json b/package.json
+index 9f2285b2a327935a64443dfff3b4389d2df0620d..b2a923b42f4a3f0fda68a9707cf65ac6007502e6 100644
+--- a/package.json
++++ b/package.json
+@@ -15,271 +15,316 @@
+     "./package.json": "./package.json",
+     ".": {
+       "import": "./index.js",
+-      "require": "./dist/index.cjs"
++      "require": "./dist/index.cjs",
++      "types": "./index.d.ts"
+     },
+     "./array.js": "./array.js",
+     "./dist/array.cjs": "./dist/array.cjs",
+     "./array": {
+       "import": "./array.js",
+-      "require": "./dist/array.cjs"
++      "require": "./dist/array.cjs",
++      "types": "./array.d.ts"
+     },
+     "./binary.js": "./binary.js",
+     "./dist/binary.cjs": "./dist/binary.cjs",
+     "./binary": {
+       "import": "./binary.js",
+-      "require": "./dist/binary.cjs"
++      "require": "./dist/binary.cjs",
++      "types": "./binary.d.ts"
+     },
+     "./broadcastchannel.js": "./broadcastchannel.js",
+     "./dist/broadcastchannel.cjs": "./dist/broadcastchannel.cjs",
+     "./broadcastchannel": {
+       "import": "./broadcastchannel.js",
+-      "require": "./dist/broadcastchannel.cjs"
++      "require": "./dist/broadcastchannel.cjs",
++      "types": "./broadcastchannel.d.ts"
+     },
+     "./buffer.js": "./buffer.js",
+     "./dist/buffer.cjs": "./dist/buffer.cjs",
+     "./buffer": {
+       "import": "./buffer.js",
+-      "require": "./dist/buffer.cjs"
++      "require": "./dist/buffer.cjs",
++      "types": "./buffer.d.ts"
+     },
+     "./cache.js": "./cache.js",
+     "./dist/cache.cjs": "./dist/cache.cjs",
+     "./cache": {
+       "import": "./cache.js",
+-      "require": "./dist/cache.cjs"
++      "require": "./dist/cache.cjs",
++      "types": "./cache.d.ts"
+     },
+     "./component.js": "./component.js",
+     "./dist/component.cjs": "./dist/component.cjs",
+     "./component": {
+       "import": "./component.js",
+-      "require": "./dist/component.cjs"
++      "require": "./dist/component.cjs",
++      "types": "./component.d.ts"
+     },
+     "./conditions.js": "./conditions.js",
+     "./dist/conditions.cjs": "./dist/conditions.cjs",
+     "./conditions": {
+       "import": "./condititons.js",
+-      "require": "./dist/conditions.cjs"
++      "require": "./dist/conditions.cjs",
++      "types": "./conditions.d.ts"
+     },
+     "./decoding.js": "./decoding.js",
+     "./dist/decoding.cjs": "./dist/decoding.cjs",
+     "./decoding": {
+       "import": "./decoding.js",
+-      "require": "./dist/decoding.cjs"
++      "require": "./dist/decoding.cjs",
++      "types": "./decoding.d.ts"
+     },
+     "./diff.js": "./diff.js",
+     "./dist/diff.cjs": "./dist/diff.cjs",
+     "./diff": {
+       "import": "./diff.js",
+-      "require": "./dist/diff.cjs"
++      "require": "./dist/diff.cjs",
++      "types": "./diff.d.ts"
+     },
+     "./dom.js": "./dom.js",
+     "./dist/dom.cjs": "./dist/dom.cjs",
+     "./dom": {
+       "import": "./dom.js",
+-      "require": "./dist/dom.cjs"
++      "require": "./dist/dom.cjs",
++      "types": "./dom.d.ts"
+     },
+     "./encoding.js": "./encoding.js",
+     "./dist/encoding.cjs": "./dist/encoding.cjs",
+     "./encoding": {
+       "import": "./encoding.js",
+-      "require": "./dist/encoding.cjs"
++      "require": "./dist/encoding.cjs",
++      "types": "./encoding.d.ts"
+     },
+     "./environment.js": "./environment.js",
+     "./dist/environment.cjs": "./dist/environment.cjs",
+     "./environment": {
+       "import": "./environment.js",
+-      "require": "./dist/environment.cjs"
++      "require": "./dist/environment.cjs",
++      "types": "./environment.d.ts"
+     },
+     "./error.js": "./error.js",
+     "./dist/error.cjs": "./dist/error.cjs",
+     "./error": {
+       "import": "./error.js",
+-      "require": "./dist/error.cjs"
++      "require": "./dist/error.cjs",
++      "types": "./error.d.ts"
+     },
+     "./eventloop.js": "./eventloop.js",
+     "./dist/eventloop.cjs": "./dist/eventloop.cjs",
+     "./eventloop": {
+       "import": "./eventloop.js",
+-      "require": "./dist/eventloop.cjs"
++      "require": "./dist/eventloop.cjs",
++      "types": "./eventloop.d.ts"
+     },
+     "./function.js": "./function.js",
+     "./dist/function.cjs": "./dist/function.cjs",
+     "./function": {
+       "import": "./function.js",
+-      "require": "./dist/function.cjs"
++      "require": "./dist/function.cjs",
++      "types": "./function.d.ts"
+     },
+     "./indexeddb.js": "./indexeddb.js",
+     "./dist/indexeddb.cjs": "./dist/indexeddb.cjs",
+     "./indexeddb": {
+       "import": "./indexeddb.js",
+-      "require": "./dist/indexeddb.cjs"
++      "require": "./dist/indexeddb.cjs",
++      "types": "./indexeddb.d.ts"
+     },
+     "./isomorphic.js": "./isomorphic.js",
+     "./dist/isomorphic.cjs": "./dist/isomorphic.cjs",
+     "./isomorphic": {
+       "import": "./isomorphic.js",
+-      "require": "./dist/isomorphic.cjs"
++      "require": "./dist/isomorphic.cjs",
++      "types": "./isomorphic.d.ts"
+     },
+     "./iterator.js": "./iterator.js",
+     "./dist/iterator.cjs": "./dist/iterator.cjs",
+     "./iterator": {
+       "import": "./iterator.js",
+-      "require": "./dist/iterator.cjs"
++      "require": "./dist/iterator.cjs",
++      "types": "./iterator.d.ts"
+     },
+     "./json.js": "./json.js",
+     "./dist/json.cjs": "./dist/json.cjs",
+     "./json": {
+       "import": "./json.js",
+-      "require": "./dist/json.cjs"
++      "require": "./dist/json.cjs",
++      "types": "./json.d.ts"
+     },
+     "./list.js": "./list.js",
+     "./dist/list.cjs": "./dist/list.cjs",
+     "./list": {
+       "import": "./list.js",
+-      "require": "./dist/list.cjs"
++      "require": "./dist/list.cjs",
++      "types": "./list.d.ts"
+     },
+     "./logging.js": "./logging.js",
+     "./dist/logging.cjs": "./dist/logging.cjs",
+     "./logging": {
+       "import": "./logging.js",
+-      "require": "./dist/logging.cjs"
++      "require": "./dist/logging.cjs",
++      "types": "./logging.d.ts"
+     },
+     "./map.js": "./map.js",
+     "./dist/map.cjs": "./dist/map.cjs",
+     "./map": {
+       "import": "./map.js",
+-      "require": "./dist/map.cjs"
++      "require": "./dist/map.cjs",
++      "types": "./map.d.ts"
+     },
+     "./math.js": "./math.js",
+     "./dist/math.cjs": "./dist/math.cjs",
+     "./math": {
+       "import": "./math.js",
+-      "require": "./dist/math.cjs"
++      "require": "./dist/math.cjs",
++      "types": "./math.d.ts"
+     },
+     "./metric.js": "./metric.js",
+     "./dist/metric.cjs": "./dist/metric.cjs",
+     "./metric": {
+       "import": "./metric.js",
+-      "require": "./dist/metric.cjs"
++      "require": "./dist/metric.cjs",
++      "types": "./metric.d.ts"
+     },
+     "./mutex.js": "./mutex.js",
+     "./dist/mutex.cjs": "./dist/mutex.cjs",
+     "./mutex": {
+       "import": "./mutex.js",
+-      "require": "./dist/mutex.cjs"
++      "require": "./dist/mutex.cjs",
++      "types": "./mutex.d.ts"
+     },
+     "./number.js": "./number.js",
+     "./dist/number.cjs": "./dist/number.cjs",
+     "./number": {
+       "import": "./number.js",
+-      "require": "./dist/number.cjs"
++      "require": "./dist/number.cjs",
++      "types": "./number.d.ts"
+     },
+     "./object.js": "./object.js",
+     "./dist/object.cjs": "./dist/object.cjs",
+     "./object": {
+       "import": "./object.js",
+-      "require": "./dist/object.cjs"
++      "require": "./dist/object.cjs",
++      "types": "./object.d.ts"
+     },
+     "./observable.js": "./observable.js",
+     "./dist/observable.cjs": "./dist/observable.cjs",
+     "./observable": {
+       "import": "./observable.js",
+-      "require": "./dist/observable.cjs"
++      "require": "./dist/observable.cjs",
++      "types": "./observable.d.ts"
+     },
+     "./pair.js": "./pair.js",
+     "./dist/pair.cjs": "./dist/pair.cjs",
+     "./pair": {
+       "import": "./pair.js",
+-      "require": "./dist/pair.cjs"
++      "require": "./dist/pair.cjs",
++      "types": "./pair.d.ts"
+     },
+     "./prng.js": "./prng.js",
+     "./dist/prng.cjs": "./dist/prng.cjs",
+     "./prng": {
+       "import": "./prng.js",
+-      "require": "./dist/prng.cjs"
++      "require": "./dist/prng.cjs",
++      "types": "./prng.d.ts"
+     },
+     "./promise.js": "./promise.js",
+     "./dist/promise.cjs": "./dist/promise.cjs",
+     "./promise": {
+       "import": "./promise.js",
+-      "require": "./dist/promise.cjs"
++      "require": "./dist/promise.cjs",
++      "types": "./promise.d.ts"
+     },
+     "./queue.js": "./queue.js",
+     "./dist/queue.cjs": "./dist/queue.cjs",
+     "./queue": {
+       "import": "./queue.js",
+-      "require": "./dist/queue.cjs"
++      "require": "./dist/queue.cjs",
++      "types": "./queue.d.ts"
+     },
+     "./random.js": "./random.js",
+     "./dist/random.cjs": "./dist/random.cjs",
+     "./random": {
+       "import": "./random.js",
+-      "require": "./dist/random.cjs"
++      "require": "./dist/random.cjs",
++      "types": "./random.d.ts"
+     },
+     "./set.js": "./set.js",
+     "./dist/set.cjs": "./dist/set.cjs",
+     "./set": {
+       "import": "./set.js",
+-      "require": "./dist/set.cjs"
++      "require": "./dist/set.cjs",
++      "types": "./set.d.ts"
+     },
+     "./sort.js": "./sort.js",
+     "./dist/sort.cjs": "./dist/sort.cjs",
+     "./sort": {
+       "import": "./sort.js",
+-      "require": "./dist/sort.cjs"
++      "require": "./dist/sort.cjs",
++      "types": "./sort.d.ts"
+     },
+     "./statistics.js": "./statistics.js",
+     "./dist/statistics.cjs": "./dist/statistics.cjs",
+     "./statistics": {
+       "import": "./statistics.js",
+-      "require": "./dist/statistics.cjs"
++      "require": "./dist/statistics.cjs",
++      "types": "./statistics.d.ts"
+     },
+     "./storage.js": "./storage.js",
+     "./dist/storage.cjs": "./dist/storage.cjs",
+     "./storage": {
+       "import": "./storage.js",
+-      "require": "./dist/storage.cjs"
++      "require": "./dist/storage.cjs",
++      "types": "./storage.d.ts"
+     },
+     "./string.js": "./string.js",
+     "./dist/string.cjs": "./dist/string.cjs",
+     "./string": {
+       "import": "./string.js",
+-      "require": "./dist/string.cjs"
++      "require": "./dist/string.cjs",
++      "types": "./string.d.ts"
+     },
+     "./symbol.js": "./symbol.js",
+     "./dist/symbol.cjs": "./dist/symbol.cjs",
+     "./symbol": {
+       "import": "./symbol.js",
+-      "require": "./dist/symbol.cjs"
++      "require": "./dist/symbol.cjs",
++      "types": "./symbol.d.ts"
+     },
+     "./testing.js": "./testing.js",
+     "./dist/testing.cjs": "./dist/testing.cjs",
+     "./testing": {
+       "import": "./testing.js",
+-      "require": "./dist/testing.cjs"
++      "require": "./dist/testing.cjs",
++      "types": "./testing.d.ts"
+     },
+     "./time.js": "./time.js",
+     "./dist/time.cjs": "./dist/time.cjs",
+     "./time": {
+       "import": "./time.js",
+-      "require": "./dist/time.cjs"
++      "require": "./dist/time.cjs",
++      "types": "./time.d.ts"
+     },
+     "./tree.js": "./tree.js",
+     "./dist/tree.cjs": "./dist/tree.cjs",
+     "./tree": {
+       "import": "./tree.js",
+-      "require": "./dist/tree.cjs"
++      "require": "./dist/tree.cjs",
++      "types": "./tree.d.ts"
+     },
+     "./url.js": "./url.js",
+     "./dist/url.cjs": "./dist/url.cjs",
+     "./url": {
+       "import": "./url.js",
+-      "require": "./dist/url.cjs"
++      "require": "./dist/url.cjs",
++      "types": "./url.d.ts"
+     },
+     "./websocket.js": "./websocket.js",
+     "./dist/websocket.cjs": "./dist/websocket.cjs",
+     "./websocket": {
+       "import": "./websocket.js",
+-      "require": "./dist/websocket.cjs"
++      "require": "./dist/websocket.cjs",
++      "types": "./websocket.d.ts"
+     }
+   },
+   "dependencies": {

.yarn/patches/y-protocols-npm-1.0.5-af6f64b4df.patch

@@ -0,0 +1,26 @@
+diff --git a/package.json b/package.json
+index 5f953f00544710a638dc502b30841d39193f6d3f..6c31784d1b1f32ee8f21106011c4e6ef526f1560 100644
+--- a/package.json
++++ b/package.json
+@@ -47,18 +47,21 @@
+     "./sync.js": "./sync.js",
+     "./dist/sync.cjs": "./dist/sync.cjs",
+     "./sync": {
++      "types": "./sync.d.ts",
+       "import": "./sync.js",
+       "require": "./dist/sync.cjs"
+     },
+     "./awareness.js": "./awareness.js",
+     "./dist/awareness.cjs": "./dist/awareness.cjs",
+     "./awareness": {
++      "types": "./awareness.d.ts",
+       "import": "./awareness.js",
+       "require": "./dist/awareness.cjs"
+     },
+     "./auth.js": "./auth.js",
+     "./dist/auth.cjs": "./dist/auth.cjs",
+     "./auth": {
++      "types": "./auth.d.ts",
+       "import": "./auth.js",
+       "require": "./dist/auth.cjs"
+     }

commons/.eslintrc.cjs

@@ -0,0 +1,40 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+module.exports = {
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+        "project": [
+            "./tsconfig-eslint.json"
+        ]
+    },
+    "plugins": [
+        "@typescript-eslint",
+        "jest",
+        "prettier"
+    ],
+    "env": {
+        "jest": true,
+        "jest/globals": true
+    },
+    "extends": [
+        "eslint:recommended",
+        "plugin:@typescript-eslint/eslint-recommended",
+        "plugin:@typescript-eslint/recommended-requiring-type-checking",
+        "plugin:@typescript-eslint/recommended",
+        "prettier"
+    ],
+    "rules": {
+        "prettier/prettier": ["error",
+            require('./.prettierrc.json')
+        ],
+        "jest/no-disabled-tests": "warn",
+        "jest/no-focused-tests": "error",
+        "jest/no-identical-title": "error",
+        "jest/prefer-to-have-length": "warn",
+        "jest/valid-expect": "error"
+    }
+}

commons/.gitignore

@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+#
+# SPDX-License-Identifier: CC0-1.0
+
+# dependencies
+/node_modules
+/.pnp
+.pnp.*
+
+# package manager
+.yarn/*
+!.yarn/patches
+!.yarn/plugins
+!.yarn/releases
+!.yarn/sdks
+!.yarn/versions
+
+# testing
+/coverage
+
+# production
+/dist
+
+# misc
+.DS_Store
+*.pem
+
+# debug
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*

commons/.npmignore

@@ -0,0 +1,9 @@
+.idea
+.babelrc
+.eslintrc
+.travis.yml
+karma.conf.js
+tests.webpack.js
+webpack.config.*.js
+coverage/
+test/

commons/.npmignore.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

commons/.prettierignore

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

commons/.prettierignore.license

@@ -0,0 +1,4 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0
+

commons/.prettierrc.json

@@ -0,0 +1,11 @@
+{
+  "parser": "typescript",
+  "singleQuote": true,
+  "jsxSingleQuote": true,
+  "semi": false,
+  "tabWidth": 2,
+  "trailingComma": "none",
+  "bracketSpacing": true,
+  "bracketSameLine": true,
+  "arrowParens": "always"
+}

commons/.prettierrc.json.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

commons/jest.config.json

@@ -0,0 +1,25 @@
+{
+  "testRegex" : "(/__tests__/.*|\\.(test|spec))\\.(ts|tsx|js)$",
+  "testPathIgnorePatterns" : [
+    "/dist/"
+  ],
+  "moduleFileExtensions" : [
+    "ts",
+    "tsx",
+    "js"
+  ],
+  "extensionsToTreatAsEsm" : [
+    ".ts"
+  ],
+  "moduleNameMapper" : {
+    "^(\\.{1,2}/.*)\\.js$" : "$1"
+  },
+  "transform" : {
+    "^.+\\.tsx?$" : [
+      "ts-jest",
+      {
+        "useESM" : true
+      }
+    ]
+  }
+}

commons/jest.config.json.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

commons/package.json

@@ -0,0 +1,60 @@
+{
+  "name": "@hedgedoc/commons",
+  "private": true,
+  "version": "0.3.0",
+  "description": "Common code between frontend and backend",
+  "author": "The HedgeDoc Authors",
+  "license": "AGPL-3.0",
+  "scripts": {
+    "build": "rm -rf dist && microbundle",
+    "build:watch": "rm -rf dist && microbundle -w",
+    "test": "jest",
+    "prepublish": "rm -rf dist && yarn lint && yarn build && yarn test",
+    "lint": "eslint src --ext .ts",
+    "lint:fix": "eslint --fix --ext .ts src"
+  },
+  "type": "module",
+  "main": "dist/index.cjs",
+  "module": "dist/index.mjs",
+  "types": "dist/index.d.ts",
+  "source": "src/index.ts",
+  "exports": {
+    "types": "./dist/index.d.ts",
+    "import": "./dist/index.mjs",
+    "require": "./dist/index.cjs"
+  },
+  "files": [
+    "LICENSES/*",
+    "package.json",
+    "README.md",
+    "dist/**"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/hedgedoc/hedgedoc.git"
+  },
+  "dependencies": {
+    "eventemitter2": "^6.4.9",
+    "isomorphic-ws": "^5.0.0",
+    "lib0": "^0.2.51",
+    "ws": "^8.0.0",
+    "y-protocols": "^1.0.0",
+    "yjs": "13.5.43"
+  },
+  "devDependencies": {
+    "@jest/types": "29.3.1",
+    "@types/ws": "8.5.3",
+    "@typescript-eslint/eslint-plugin": "5.44.0",
+    "@typescript-eslint/parser": "5.44.0",
+    "eslint": "8.29.0",
+    "eslint-config-prettier": "8.5.0",
+    "eslint-plugin-jest": "27.1.6",
+    "eslint-plugin-prettier": "4.2.1",
+    "jest": "29.3.1",
+    "microbundle": "0.15.1",
+    "prettier": "2.8.1",
+    "ts-jest": "29.0.3",
+    "typescript": "4.9.3"
+  },
+  "packageManager": "yarn@3.3.0"
+}

commons/package.json.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

commons/src/connection-keep-alive-handler.ts

@@ -0,0 +1,77 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './messages/message-type.enum.js'
+import type { YDocMessageTransporter } from './y-doc-message-transporter.js'
+import { createEncoder, toUint8Array, writeVarUint } from 'lib0/encoding'
+
+/**
+ * Provides a keep alive ping for a given {@link WebSocket websocket} connection by sending a periodic message.
+ */
+export class ConnectionKeepAliveHandler {
+  private pongReceived = false
+  private static readonly pingTimeout = 30 * 1000
+  private intervalId: NodeJS.Timer | undefined
+
+  /**
+   * Constructs the instance and starts the interval.
+   *
+   * @param messageTransporter The websocket to keep alive
+   */
+  constructor(private messageTransporter: YDocMessageTransporter) {
+    this.messageTransporter.on('disconnected', () => this.stopTimer())
+    this.messageTransporter.on('ready', () => this.startTimer())
+    this.messageTransporter.on(String(MessageType.PING), () => {
+      this.sendPongMessage()
+    })
+    this.messageTransporter.on(
+      String(MessageType.PONG),
+      () => (this.pongReceived = true)
+    )
+  }
+
+  /**
+   * Starts the ping timer.
+   */
+  public startTimer(): void {
+    this.pongReceived = false
+    this.intervalId = setInterval(
+      () => this.check(),
+      ConnectionKeepAliveHandler.pingTimeout
+    )
+    this.sendPingMessage()
+  }
+
+  public stopTimer(): void {
+    clearInterval(this.intervalId)
+  }
+
+  /**
+   * Checks if a pong has been received since the last run. If not, the connection is probably dead and will be terminated.
+   */
+  private check(): void {
+    if (this.pongReceived) {
+      this.pongReceived = false
+      this.sendPingMessage()
+    } else {
+      this.messageTransporter.disconnect()
+      console.error(
+        `No pong received in the last ${ConnectionKeepAliveHandler.pingTimeout} seconds. Connection seems to be dead.`
+      )
+    }
+  }
+
+  private sendPingMessage(): void {
+    const encoder = createEncoder()
+    writeVarUint(encoder, MessageType.PING)
+    this.messageTransporter.send(toUint8Array(encoder))
+  }
+
+  private sendPongMessage(): void {
+    const encoder = createEncoder()
+    writeVarUint(encoder, MessageType.PONG)
+    this.messageTransporter.send(toUint8Array(encoder))
+  }
+}

commons/src/index.ts

@@ -0,0 +1,27 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export { MessageType } from './messages/message-type.enum.js'
+export { ConnectionKeepAliveHandler } from './connection-keep-alive-handler.js'
+export { YDocMessageTransporter } from './y-doc-message-transporter.js'
+export {
+  applyAwarenessUpdateMessage,
+  encodeAwarenessUpdateMessage
+} from './messages/awareness-update-message.js'
+export {
+  applyDocumentUpdateMessage,
+  encodeDocumentUpdateMessage
+} from './messages/document-update-message.js'
+export { encodeCompleteAwarenessStateRequestMessage } from './messages/complete-awareness-state-request-message.js'
+export { encodeCompleteDocumentStateRequestMessage } from './messages/complete-document-state-request-message.js'
+export { encodeCompleteDocumentStateAnswerMessage } from './messages/complete-document-state-answer-message.js'
+export { encodeDocumentDeletedMessage } from './messages/document-deleted-message.js'
+export { encodeMetadataUpdatedMessage } from './messages/metadata-updated-message.js'
+export { encodeServerVersionUpdatedMessage } from './messages/server-version-updated-message.js'
+
+export { WebsocketTransporter } from './websocket-transporter.js'
+
+export type { MessageTransporterEvents } from './y-doc-message-transporter.js'

commons/src/messages/awareness-update-message.ts

@@ -0,0 +1,40 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './message-type.enum.js'
+import type { Decoder } from 'lib0/decoding'
+import { readVarUint8Array } from 'lib0/decoding'
+import {
+  createEncoder,
+  toUint8Array,
+  writeVarUint,
+  writeVarUint8Array
+} from 'lib0/encoding'
+import type { Awareness } from 'y-protocols/awareness'
+import {
+  applyAwarenessUpdate,
+  encodeAwarenessUpdate
+} from 'y-protocols/awareness'
+
+export function applyAwarenessUpdateMessage(
+  decoder: Decoder,
+  awareness: Awareness,
+  origin: unknown
+): void {
+  applyAwarenessUpdate(awareness, readVarUint8Array(decoder), origin)
+}
+
+export function encodeAwarenessUpdateMessage(
+  awareness: Awareness,
+  updatedClientIds: number[]
+): Uint8Array {
+  const encoder = createEncoder()
+  writeVarUint(encoder, MessageType.AWARENESS_UPDATE)
+  writeVarUint8Array(
+    encoder,
+    encodeAwarenessUpdate(awareness, updatedClientIds)
+  )
+  return toUint8Array(encoder)
+}

commons/src/messages/complete-awareness-state-request-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeCompleteAwarenessStateRequestMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.COMPLETE_AWARENESS_STATE_REQUEST)
+}

commons/src/messages/complete-document-state-answer-message.ts

@@ -0,0 +1,29 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './message-type.enum.js'
+import { decoding } from 'lib0'
+import { Decoder } from 'lib0/decoding'
+import {
+  createEncoder,
+  toUint8Array,
+  writeVarUint,
+  writeVarUint8Array
+} from 'lib0/encoding'
+import type { Doc } from 'yjs'
+import { encodeStateAsUpdate } from 'yjs'
+
+export function encodeCompleteDocumentStateAnswerMessage(
+  doc: Doc,
+  decoder: Decoder
+): Uint8Array {
+  const encoder = createEncoder()
+  writeVarUint(encoder, MessageType.COMPLETE_DOCUMENT_STATE_ANSWER)
+  writeVarUint8Array(
+    encoder,
+    encodeStateAsUpdate(doc, decoding.readVarUint8Array(decoder))
+  )
+  return toUint8Array(encoder)
+}

commons/src/messages/complete-document-state-request-message.ts

@@ -0,0 +1,23 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './message-type.enum.js'
+import {
+  createEncoder,
+  toUint8Array,
+  writeVarUint,
+  writeVarUint8Array
+} from 'lib0/encoding'
+import type { Doc } from 'yjs'
+import { encodeStateVector } from 'yjs'
+
+export function encodeCompleteDocumentStateRequestMessage(
+  doc: Doc
+): Uint8Array {
+  const encoder = createEncoder()
+  writeVarUint(encoder, MessageType.COMPLETE_DOCUMENT_STATE_REQUEST)
+  writeVarUint8Array(encoder, encodeStateVector(doc))
+  return toUint8Array(encoder)
+}

commons/src/messages/document-deleted-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeDocumentDeletedMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.DOCUMENT_DELETED)
+}

commons/src/messages/document-update-message.ts

@@ -0,0 +1,33 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './message-type.enum.js'
+import { readVarUint8Array } from 'lib0/decoding'
+import type { Decoder } from 'lib0/decoding.js'
+import {
+  createEncoder,
+  toUint8Array,
+  writeVarUint,
+  writeVarUint8Array
+} from 'lib0/encoding'
+import type { Doc } from 'yjs'
+import { applyUpdate } from 'yjs'
+
+export function applyDocumentUpdateMessage(
+  decoder: Decoder,
+  doc: Doc,
+  origin: unknown
+): void {
+  applyUpdate(doc, readVarUint8Array(decoder), origin)
+}
+
+export function encodeDocumentUpdateMessage(
+  documentUpdate: Uint8Array
+): Uint8Array {
+  const encoder = createEncoder()
+  writeVarUint(encoder, MessageType.DOCUMENT_UPDATE)
+  writeVarUint8Array(encoder, documentUpdate)
+  return toUint8Array(encoder)
+}

commons/src/messages/generic-message.ts

@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { MessageType } from './message-type.enum.js'
+import { createEncoder, toUint8Array, writeVarUint } from 'lib0/encoding'
+
+/**
+ * Encodes a generic message with a given message type but without content.
+ */
+export function encodeGenericMessage(messageType: MessageType): Uint8Array {
+  const encoder = createEncoder()
+  writeVarUint(encoder, messageType)
+  return toUint8Array(encoder)
+}

commons/src/messages/message-type.enum.ts

@@ -0,0 +1,20 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export enum MessageType {
+  COMPLETE_DOCUMENT_STATE_REQUEST = 0,
+  COMPLETE_DOCUMENT_STATE_ANSWER = 1,
+  DOCUMENT_UPDATE = 2,
+  AWARENESS_UPDATE = 3,
+  COMPLETE_AWARENESS_STATE_REQUEST = 4,
+  PING = 5,
+  PONG = 6,
+  READY_REQUEST = 7,
+  READY_ANSWER = 8,
+  METADATA_UPDATED = 9,
+  DOCUMENT_DELETED = 10,
+  SERVER_VERSION_UPDATED = 11
+}

commons/src/messages/metadata-updated-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeMetadataUpdatedMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.METADATA_UPDATED)
+}

commons/src/messages/ready-answer-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeReadyAnswerMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.READY_ANSWER)
+}

commons/src/messages/ready-request-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeReadyRequestMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.READY_REQUEST)
+}

commons/src/messages/server-version-updated-message.ts

@@ -0,0 +1,11 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeGenericMessage } from './generic-message.js'
+import { MessageType } from './message-type.enum.js'
+
+export function encodeServerVersionUpdatedMessage(): Uint8Array {
+  return encodeGenericMessage(MessageType.SERVER_VERSION_UPDATED)
+}

commons/src/websocket-transporter.ts

@@ -0,0 +1,61 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { ConnectionKeepAliveHandler } from './connection-keep-alive-handler.js'
+import { YDocMessageTransporter } from './y-doc-message-transporter.js'
+import WebSocket from 'isomorphic-ws'
+import { Awareness } from 'y-protocols/awareness'
+import { Doc } from 'yjs'
+
+export class WebsocketTransporter extends YDocMessageTransporter {
+  private websocket: WebSocket | undefined
+
+  constructor(doc: Doc, awareness: Awareness) {
+    super(doc, awareness)
+    new ConnectionKeepAliveHandler(this)
+  }
+
+  public setupWebsocket(websocket: WebSocket) {
+    if (
+      websocket.readyState === WebSocket.CLOSED ||
+      websocket.readyState === WebSocket.CLOSING
+    ) {
+      throw new Error(`Socket is closed`)
+    }
+    this.websocket = websocket
+    websocket.binaryType = 'arraybuffer'
+    websocket.addEventListener('message', (event) =>
+      this.decodeMessage(event.data as ArrayBuffer)
+    )
+    websocket.addEventListener('error', () => this.disconnect())
+    websocket.addEventListener('close', () => this.onClose())
+    if (websocket.readyState === WebSocket.OPEN) {
+      this.onOpen()
+    } else {
+      websocket.addEventListener('open', this.onOpen.bind(this))
+    }
+  }
+
+  public disconnect(): void {
+    this.websocket?.close()
+  }
+
+  public send(content: Uint8Array): void {
+    if (this.websocket?.readyState !== WebSocket.OPEN) {
+      throw new Error("Can't send message over non-open socket")
+    }
+
+    try {
+      this.websocket.send(content)
+    } catch (error: unknown) {
+      this.disconnect()
+      throw error
+    }
+  }
+
+  public isWebSocketOpen(): boolean {
+    return this.websocket?.readyState === WebSocket.OPEN
+  }
+}

commons/src/y-doc-message-transporter.test.ts

@@ -0,0 +1,206 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { encodeDocumentUpdateMessage } from './messages/document-update-message.js'
+import { MessageType } from './messages/message-type.enum.js'
+import { YDocMessageTransporter } from './y-doc-message-transporter.js'
+import { describe, expect, it } from '@jest/globals'
+import { Awareness } from 'y-protocols/awareness'
+import { Doc } from 'yjs'
+
+class InMemoryMessageTransporter extends YDocMessageTransporter {
+  private otherSide: InMemoryMessageTransporter | undefined
+
+  constructor(private name: string, doc: Doc, awareness: Awareness) {
+    super(doc, awareness)
+  }
+
+  public connect(other: InMemoryMessageTransporter): void {
+    this.setOtherSide(other)
+    other.setOtherSide(this)
+    this.onOpen()
+    other.onOpen()
+  }
+
+  private setOtherSide(other: InMemoryMessageTransporter | undefined): void {
+    this.otherSide = other
+  }
+
+  public disconnect(): void {
+    this.onClose()
+    this.setOtherSide(undefined)
+    this.otherSide?.onClose()
+    this.otherSide?.setOtherSide(undefined)
+  }
+
+  send(content: Uint8Array): void {
+    if (this.otherSide === undefined) {
+      throw new Error('Disconnected')
+    }
+    console.debug(`${this.name}`, 'Sending', content)
+    this.otherSide?.decodeMessage(content)
+  }
+
+  public onOpen(): void {
+    super.onOpen()
+  }
+}
+
+describe('message transporter', () =>
+  it('server client communication', () => {
+    const docServer: Doc = new Doc()
+    const docClient1: Doc = new Doc()
+    const docClient2: Doc = new Doc()
+    const dummyAwareness: Awareness = new Awareness(docServer)
+
+    const textServer = docServer.getText('markdownContent')
+    const textClient1 = docClient1.getText('markdownContent')
+    const textClient2 = docClient2.getText('markdownContent')
+    textServer.insert(0, 'This is a test note')
+
+    textServer.observe(() =>
+      console.debug('textServer', new Date(), textServer.toString())
+    )
+    textClient1.observe(() =>
+      console.debug('textClient1', new Date(), textClient1.toString())
+    )
+    textClient2.observe(() =>
+      console.debug('textClient2', new Date(), textClient2.toString())
+    )
+
+    const transporterServerTo1 = new InMemoryMessageTransporter(
+      's>1',
+      docServer,
+      dummyAwareness
+    )
+    const transporterServerTo2 = new InMemoryMessageTransporter(
+      's>2',
+      docServer,
+      dummyAwareness
+    )
+    const transporterClient1 = new InMemoryMessageTransporter(
+      '1>s',
+      docClient1,
+      dummyAwareness
+    )
+    const transporterClient2 = new InMemoryMessageTransporter(
+      '2>s',
+      docClient2,
+      dummyAwareness
+    )
+
+    transporterServerTo1.on(String(MessageType.DOCUMENT_UPDATE), () =>
+      console.debug('Received DOCUMENT_UPDATE from client 1 to server')
+    )
+    transporterServerTo2.on(String(MessageType.DOCUMENT_UPDATE), () =>
+      console.debug('Received DOCUMENT_UPDATE from client 2 to server')
+    )
+    transporterClient1.on(String(MessageType.DOCUMENT_UPDATE), () =>
+      console.debug('Received DOCUMENT_UPDATE from server to client 1')
+    )
+    transporterClient2.on(String(MessageType.DOCUMENT_UPDATE), () =>
+      console.debug('Received DOCUMENT_UPDATE from server to client 2')
+    )
+
+    transporterServerTo1.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_ANSWER),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_ANSWER from client 1 to server'
+        )
+    )
+    transporterServerTo2.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_ANSWER),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_ANSWER from client 2 to server'
+        )
+    )
+    transporterClient1.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_ANSWER),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_ANSWER from server to client 1'
+        )
+    )
+    transporterClient2.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_ANSWER),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_ANSWER from server to client 2'
+        )
+    )
+
+    transporterServerTo1.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_REQUEST),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_REQUEST from client 1 to server'
+        )
+    )
+    transporterServerTo2.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_REQUEST),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_REQUEST from client 2 to server'
+        )
+    )
+    transporterClient1.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_REQUEST),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_REQUEST from server to client 1'
+        )
+    )
+    transporterClient2.on(
+      String(MessageType.COMPLETE_DOCUMENT_STATE_REQUEST),
+      () =>
+        console.debug(
+          'Received COMPLETE_DOCUMENT_STATE_REQUEST from server to client 2'
+        )
+    )
+    transporterClient1.on('ready', () => console.debug('Client 1 is ready'))
+    transporterClient2.on('ready', () => console.debug('Client 2 is ready'))
+
+    docServer.on('update', (update: Uint8Array, origin: unknown) => {
+      const message = encodeDocumentUpdateMessage(update)
+      if (origin !== transporterServerTo1) {
+        console.debug('YDoc on Server updated. Sending to Client 1')
+        transporterServerTo1.send(message)
+      }
+      if (origin !== transporterServerTo2) {
+        console.debug('YDoc on Server updated. Sending to Client 2')
+        transporterServerTo2.send(message)
+      }
+    })
+    docClient1.on('update', (update: Uint8Array, origin: unknown) => {
+      if (origin !== transporterClient1) {
+        console.debug('YDoc on client 1 updated. Sending to Server')
+        transporterClient1.send(encodeDocumentUpdateMessage(update))
+      }
+    })
+    docClient2.on('update', (update: Uint8Array, origin: unknown) => {
+      if (origin !== transporterClient2) {
+        console.debug('YDoc on client 2 updated. Sending to Server')
+        transporterClient2.send(encodeDocumentUpdateMessage(update))
+      }
+    })
+
+    transporterClient1.connect(transporterServerTo1)
+    transporterClient2.connect(transporterServerTo2)
+
+    textClient1.insert(0, 'test2')
+    textClient1.insert(0, 'test3')
+    textClient2.insert(0, 'test4')
+
+    expect(textServer.toString()).toBe('test4test3test2This is a test note')
+    expect(textClient1.toString()).toBe('test4test3test2This is a test note')
+    expect(textClient2.toString()).toBe('test4test3test2This is a test note')
+
+    dummyAwareness.destroy()
+    docServer.destroy()
+    docClient1.destroy()
+    docClient2.destroy()
+  }))

commons/src/y-doc-message-transporter.ts

@@ -0,0 +1,112 @@
+/*
+ * SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import {
+  applyAwarenessUpdateMessage,
+  encodeAwarenessUpdateMessage
+} from './messages/awareness-update-message.js'
+import { encodeCompleteDocumentStateAnswerMessage } from './messages/complete-document-state-answer-message.js'
+import { encodeCompleteDocumentStateRequestMessage } from './messages/complete-document-state-request-message.js'
+import { applyDocumentUpdateMessage } from './messages/document-update-message.js'
+import { MessageType } from './messages/message-type.enum.js'
+import { encodeReadyAnswerMessage } from './messages/ready-answer-message.js'
+import { encodeReadyRequestMessage } from './messages/ready-request-message.js'
+import { EventEmitter2 } from 'eventemitter2'
+import { Decoder, readVarUint } from 'lib0/decoding'
+import { Awareness } from 'y-protocols/awareness'
+import { Doc } from 'yjs'
+
+export type Handler = (decoder: Decoder) => void
+
+export type MessageTransporterEvents = {
+  disconnected: () => void
+  connected: () => void
+  ready: () => void
+  synced: () => void
+} & Partial<Record<MessageType, Handler>>
+
+export abstract class YDocMessageTransporter extends EventEmitter2 {
+  private synced = false
+
+  protected constructor(
+    protected readonly doc: Doc,
+    protected readonly awareness: Awareness
+  ) {
+    super()
+    this.on(String(MessageType.READY_REQUEST), () => {
+      this.send(encodeReadyAnswerMessage())
+    })
+    this.on(String(MessageType.READY_ANSWER), () => {
+      this.emit('ready')
+    })
+    this.bindDocumentSyncMessageEvents(doc)
+  }
+
+  public isSynced(): boolean {
+    return this.synced
+  }
+
+  protected onOpen(): void {
+    this.emit('connected')
+    this.send(encodeReadyRequestMessage())
+  }
+
+  protected onClose(): void {
+    this.emit('disconnected')
+  }
+
+  protected markAsSynced(): void {
+    if (!this.synced) {
+      this.synced = true
+      this.emit('synced')
+    }
+  }
+
+  protected decodeMessage(buffer: ArrayBuffer): void {
+    const data = new Uint8Array(buffer)
+    const decoder = new Decoder(data)
+    const messageType = readVarUint(decoder) as MessageType
+
+    switch (messageType) {
+      case MessageType.COMPLETE_DOCUMENT_STATE_REQUEST:
+        this.send(encodeCompleteDocumentStateAnswerMessage(this.doc, decoder))
+        break
+      case MessageType.DOCUMENT_UPDATE:
+        applyDocumentUpdateMessage(decoder, this.doc, this)
+        break
+      case MessageType.COMPLETE_DOCUMENT_STATE_ANSWER:
+        applyDocumentUpdateMessage(decoder, this.doc, this)
+        this.markAsSynced()
+        break
+      case MessageType.COMPLETE_AWARENESS_STATE_REQUEST:
+        this.send(
+          encodeAwarenessUpdateMessage(this.awareness, [
+            ...this.awareness.getStates().keys()
+          ])
+        )
+        break
+      case MessageType.AWARENESS_UPDATE:
+        applyAwarenessUpdateMessage(decoder, this.awareness, this)
+    }
+
+    this.emit(String(messageType), decoder)
+  }
+
+  private bindDocumentSyncMessageEvents(doc: Doc) {
+    this.on('ready', () => {
+      this.send(encodeCompleteDocumentStateRequestMessage(doc))
+    })
+    this.on('disconnected', () => (this.synced = false))
+  }
+
+  /**
+   * Sends binary data to the client. Closes the connection on errors.
+   *
+   * @param content The binary data to send.
+   */
+  public abstract send(content: Uint8Array): void
+
+  public abstract disconnect(): void
+}

commons/tsconfig-eslint.json

@@ -0,0 +1,4 @@
+{
+  "extends": "./tsconfig.json",
+  "exclude": ["./dist"]
+}

commons/tsconfig-eslint.json.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

commons/tsconfig.json

@@ -0,0 +1,24 @@
+{
+  "compilerOptions": {
+    "target": "esnext",
+    "removeComments": true,
+    "preserveConstEnums": true,
+    "lib": [
+      "es2020",
+      "dom"
+    ],
+    "declaration": true,
+    "strict": true,
+    "allowSyntheticDefaultImports": true,
+    "forceConsistentCasingInFileNames": true,
+    "module": "esnext",
+    "moduleResolution": "NodeNext",
+    "esModuleInterop": true,
+    "outDir": "dist/",
+    "rootDir": "./src",
+    "allowJs": true,
+    "sourceMap": true
+  },
+  "include": ["./src"],
+  "exclude": ["./dist", "**/*.test.*", "**/__mocks__/*", "**/__tests__/*"]
+}

commons/tsconfig.json.license

@@ -0,0 +1,3 @@
+SPDX-FileCopyrightText: 2022 The HedgeDoc developers (see AUTHORS file)
+
+SPDX-License-Identifier: CC0-1.0

package.json

@@ -4,14 +4,21 @@
   "private": true,
   "workspaces": [
     "backend",
-    "frontend"
+    "frontend",
+    "commons"
   ],
   "packageManager": "yarn@3.3.0",
   "resolutions": {
     "domhandler": "5.0.3",
-    "yjs": "13.5.42",
     "@codemirror/state": "6.1.4",
     "@codemirror/view": "6.7.0",
-    "@codemirror/language": "6.3.1"
+    "@codemirror/language": "6.3.1",
+    "@types/react": "18.0.26",
+    "y-protocols@^1.0.0": "patch:y-protocols@npm%3A1.0.5#./.yarn/patches/y-protocols-npm-1.0.5-af6f64b4df.patch",
+    "y-protocols@1.0.5": "patch:y-protocols@npm%3A1.0.5#./.yarn/patches/y-protocols-npm-1.0.5-af6f64b4df.patch",
+    "lib0@^0.2.51": "patch:lib0@npm%3A0.2.58#./.yarn/patches/lib0-npm-0.2.58-7de44657f5.patch",
+    "lib0@^0.2.49": "patch:lib0@npm%3A0.2.58#./.yarn/patches/lib0-npm-0.2.58-7de44657f5.patch",
+    "lib0@^0.2.42": "patch:lib0@npm%3A0.2.58#./.yarn/patches/lib0-npm-0.2.58-7de44657f5.patch",
+    "lib0@0.2.58": "patch:lib0@npm%3A0.2.58#./.yarn/patches/lib0-npm-0.2.58-7de44657f5.patch"
   }
 }