From f82177a46a3609f72029f10d38566886fcdaac70 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 10:41:16 +0100
Subject: [PATCH 01/14] [Errors] migrate to OError

---
 services/real-time/app/js/Errors.js                   | 8 ++++----
 services/real-time/app/js/Router.js                   | 4 ++--
 services/real-time/package.json                       | 1 +
 services/real-time/test/unit/js/WebApiManagerTests.js | 4 +++-
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index bdda1b4c21..06bf33cf5d 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -1,8 +1,8 @@
-class CodedError extends Error {
+const OError = require('@overleaf/o-error')
+
+class CodedError extends OError {
   constructor(message, code) {
-    super(message)
-    this.name = this.constructor.name
-    this.code = code
+    super(message, { code })
   }
 }
 
diff --git a/services/real-time/app/js/Router.js b/services/real-time/app/js/Router.js
index ae10d12e2b..87c1991d4c 100644
--- a/services/real-time/app/js/Router.js
+++ b/services/real-time/app/js/Router.js
@@ -33,8 +33,8 @@ module.exports = Router = {
     attrs.client_id = client.id
     attrs.err = error
     if (error.name === 'CodedError') {
-      logger.warn(attrs, error.message, { code: error.code })
-      const serializedError = { message: error.message, code: error.code }
+      logger.warn(attrs, error.message)
+      const serializedError = { message: error.message, code: error.info.code }
       callback(serializedError)
     } else if (error.message === 'unexpected arguments') {
       // the payload might be very large, put it on level info
diff --git a/services/real-time/package.json b/services/real-time/package.json
index 4a7acfc1cd..0fab05972f 100644
--- a/services/real-time/package.json
+++ b/services/real-time/package.json
@@ -19,6 +19,7 @@
     "format:fix": "node_modules/.bin/prettier-eslint $PWD'/**/*.js' --write"
   },
   "dependencies": {
+    "@overleaf/o-error": "^3.0.0",
     "async": "^0.9.0",
     "base64id": "0.1.0",
     "basic-auth-connect": "^1.0.0",
diff --git a/services/real-time/test/unit/js/WebApiManagerTests.js b/services/real-time/test/unit/js/WebApiManagerTests.js
index 2d792b563b..52c6da137a 100644
--- a/services/real-time/test/unit/js/WebApiManagerTests.js
+++ b/services/real-time/test/unit/js/WebApiManagerTests.js
@@ -152,7 +152,9 @@ describe('WebApiManager', function () {
           .calledWith(
             sinon.match({
               message: 'rate-limit hit when joining project',
-              code: 'TooManyRequests'
+              info: {
+                code: 'TooManyRequests'
+              }
             })
           )
           .should.equal(true)

From 5950b26a42bc8e977d77eaaf054f2f907810ddca Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:03:34 +0100
Subject: [PATCH 02/14] [SafeJsonParse] migrate to OError and use a new
 DataTooLargeToParseError

---
 services/real-time/app/js/Errors.js                  | 11 ++++++++++-
 services/real-time/app/js/SafeJsonParse.js           |  8 ++------
 services/real-time/test/unit/js/SafeJsonParseTest.js |  2 +-
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 06bf33cf5d..12c644c839 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -6,4 +6,13 @@ class CodedError extends OError {
   }
 }
 
-module.exports = { CodedError }
+class DataTooLargeToParseError extends OError {
+  constructor(data) {
+    super('data too large to parse', {
+      head: data.slice(0, 1024),
+      length: data.length
+    })
+  }
+}
+
+module.exports = { CodedError, DataTooLargeToParseError }
diff --git a/services/real-time/app/js/SafeJsonParse.js b/services/real-time/app/js/SafeJsonParse.js
index 982fd9d424..a8a3afae4d 100644
--- a/services/real-time/app/js/SafeJsonParse.js
+++ b/services/real-time/app/js/SafeJsonParse.js
@@ -1,14 +1,10 @@
 const Settings = require('settings-sharelatex')
-const logger = require('logger-sharelatex')
+const { DataTooLargeToParseError } = require('./Errors')
 
 module.exports = {
   parse(data, callback) {
     if (data.length > Settings.maxUpdateSize) {
-      logger.error(
-        { head: data.slice(0, 1024), length: data.length },
-        'data too large to parse'
-      )
-      return callback(new Error('data too large to parse'))
+      return callback(new DataTooLargeToParseError(data))
     }
     let parsed
     try {
diff --git a/services/real-time/test/unit/js/SafeJsonParseTest.js b/services/real-time/test/unit/js/SafeJsonParseTest.js
index 4fb558a6b0..51a60dea23 100644
--- a/services/real-time/test/unit/js/SafeJsonParseTest.js
+++ b/services/real-time/test/unit/js/SafeJsonParseTest.js
@@ -50,7 +50,7 @@ describe('SafeJsonParse', function () {
       const data = `{\"foo\": \"${big_blob}\"}`
       this.Settings.maxUpdateSize = 2 * 1024
       return this.SafeJsonParse.parse(data, (error, parsed) => {
-        this.logger.error.called.should.equal(true)
+        this.logger.error.called.should.equal(false)
         expect(error).to.exist
         return done()
       })

From af50f9b02c768dbd7a766916ade7f5d1c4eaf54e Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:16:26 +0100
Subject: [PATCH 03/14] [DocumentUpdaterManager] use a new UpdateTooLargeError

---
 services/real-time/app/js/DocumentUpdaterManager.js       | 5 ++---
 services/real-time/app/js/Errors.js                       | 8 +++++++-
 services/real-time/app/js/WebsocketController.js          | 2 +-
 .../real-time/test/unit/js/DocumentUpdaterManagerTests.js | 2 +-
 .../real-time/test/unit/js/WebsocketControllerTests.js    | 4 ++--
 5 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/services/real-time/app/js/DocumentUpdaterManager.js b/services/real-time/app/js/DocumentUpdaterManager.js
index 3fd09d7b1d..8a2ebda1f9 100644
--- a/services/real-time/app/js/DocumentUpdaterManager.js
+++ b/services/real-time/app/js/DocumentUpdaterManager.js
@@ -6,6 +6,7 @@ const _ = require('underscore')
 const logger = require('logger-sharelatex')
 const settings = require('settings-sharelatex')
 const metrics = require('metrics-sharelatex')
+const { UpdateTooLargeError } = require('./Errors')
 
 const rclient = require('redis-sharelatex').createClient(
   settings.redis.documentupdater
@@ -125,9 +126,7 @@ const DocumentUpdaterManager = {
 
     const updateSize = jsonChange.length
     if (updateSize > settings.maxUpdateSize) {
-      const error = new Error('update is too large')
-      error.updateSize = updateSize
-      return callback(error)
+      return callback(new UpdateTooLargeError(updateSize))
     }
 
     // record metric for each update added to queue
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 12c644c839..56034023a0 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -15,4 +15,10 @@ class DataTooLargeToParseError extends OError {
   }
 }
 
-module.exports = { CodedError, DataTooLargeToParseError }
+class UpdateTooLargeError extends OError {
+  constructor(updateSize) {
+    super('update is too large', { updateSize })
+  }
+}
+
+module.exports = { CodedError, DataTooLargeToParseError, UpdateTooLargeError }
diff --git a/services/real-time/app/js/WebsocketController.js b/services/real-time/app/js/WebsocketController.js
index 8867320dbe..a0c33f5cbe 100644
--- a/services/real-time/app/js/WebsocketController.js
+++ b/services/real-time/app/js/WebsocketController.js
@@ -509,7 +509,7 @@ module.exports = WebsocketController = {
           function (error) {
             if ((error && error.message) === 'update is too large') {
               metrics.inc('update_too_large')
-              const { updateSize } = error
+              const { updateSize } = error.info
               logger.warn(
                 { user_id, project_id, doc_id, updateSize },
                 'update is too large'
diff --git a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
index dc42b52140..2ded504051 100644
--- a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
+++ b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
@@ -346,7 +346,7 @@ describe('DocumentUpdaterManager', function () {
       })
 
       it('should add the size to the error', function () {
-        return this.callback.args[0][0].updateSize.should.equal(7782422)
+        return this.callback.args[0][0].info.updateSize.should.equal(7782422)
       })
 
       return it('should not push the change onto the pending-updates-list queue', function () {
diff --git a/services/real-time/test/unit/js/WebsocketControllerTests.js b/services/real-time/test/unit/js/WebsocketControllerTests.js
index 515d407cc2..7c42dd6256 100644
--- a/services/real-time/test/unit/js/WebsocketControllerTests.js
+++ b/services/real-time/test/unit/js/WebsocketControllerTests.js
@@ -19,6 +19,7 @@ const { expect } = chai
 const modulePath = '../../../app/js/WebsocketController.js'
 const SandboxedModule = require('sandboxed-module')
 const tk = require('timekeeper')
+const { UpdateTooLargeError } = require('../../../app/js/Errors')
 
 describe('WebsocketController', function () {
   beforeEach(function () {
@@ -1507,8 +1508,7 @@ describe('WebsocketController', function () {
         this.client.emit = sinon.stub()
         this.client.ol_context.user_id = this.user_id
         this.client.ol_context.project_id = this.project_id
-        const error = new Error('update is too large')
-        error.updateSize = 7372835
+        const error = new UpdateTooLargeError(7372835)
         this.DocumentUpdaterManager.queueChange = sinon
           .stub()
           .callsArgWith(3, error)

From 6828becb46bcbdf1d9ce13a63f6a978e70b93774 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:30:22 +0100
Subject: [PATCH 04/14] [DocumentUpdaterManager] use a new NullBytesInOpError

---
 services/real-time/app/js/DocumentUpdaterManager.js |  9 ++-------
 services/real-time/app/js/Errors.js                 | 13 ++++++++++++-
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/services/real-time/app/js/DocumentUpdaterManager.js b/services/real-time/app/js/DocumentUpdaterManager.js
index 8a2ebda1f9..167bb000a4 100644
--- a/services/real-time/app/js/DocumentUpdaterManager.js
+++ b/services/real-time/app/js/DocumentUpdaterManager.js
@@ -6,7 +6,7 @@ const _ = require('underscore')
 const logger = require('logger-sharelatex')
 const settings = require('settings-sharelatex')
 const metrics = require('metrics-sharelatex')
-const { UpdateTooLargeError } = require('./Errors')
+const { NullBytesInOpError, UpdateTooLargeError } = require('./Errors')
 
 const rclient = require('redis-sharelatex').createClient(
   settings.redis.documentupdater
@@ -116,12 +116,7 @@ const DocumentUpdaterManager = {
     const jsonChange = JSON.stringify(change)
     if (jsonChange.indexOf('\u0000') !== -1) {
       // memory corruption check
-      const error = new Error('null bytes found in op')
-      logger.error(
-        { err: error, project_id, doc_id, jsonChange },
-        error.message
-      )
-      return callback(error)
+      return callback(new NullBytesInOpError(jsonChange))
     }
 
     const updateSize = jsonChange.length
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 56034023a0..dc90af856a 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -15,10 +15,21 @@ class DataTooLargeToParseError extends OError {
   }
 }
 
+class NullBytesInOpError extends OError {
+  constructor(jsonChange) {
+    super('null bytes found in op', { jsonChange })
+  }
+}
+
 class UpdateTooLargeError extends OError {
   constructor(updateSize) {
     super('update is too large', { updateSize })
   }
 }
 
-module.exports = { CodedError, DataTooLargeToParseError, UpdateTooLargeError }
+module.exports = {
+  CodedError,
+  DataTooLargeToParseError,
+  NullBytesInOpError,
+  UpdateTooLargeError
+}

From de518ea4eb27a96accc12c69dc11d6cbf5449b57 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:38:10 +0100
Subject: [PATCH 05/14] [SessionSockets] use a new MissingSessionError

---
 services/real-time/app/js/Errors.js         | 7 +++++++
 services/real-time/app/js/SessionSockets.js | 3 ++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index dc90af856a..7a039c54c1 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -15,6 +15,12 @@ class DataTooLargeToParseError extends OError {
   }
 }
 
+class MissingSessionError extends OError {
+  constructor() {
+    super('could not look up session by key')
+  }
+}
+
 class NullBytesInOpError extends OError {
   constructor(jsonChange) {
     super('null bytes found in op', { jsonChange })
@@ -30,6 +36,7 @@ class UpdateTooLargeError extends OError {
 module.exports = {
   CodedError,
   DataTooLargeToParseError,
+  MissingSessionError,
   NullBytesInOpError,
   UpdateTooLargeError
 }
diff --git a/services/real-time/app/js/SessionSockets.js b/services/real-time/app/js/SessionSockets.js
index 4ade959829..84f87bf872 100644
--- a/services/real-time/app/js/SessionSockets.js
+++ b/services/real-time/app/js/SessionSockets.js
@@ -1,7 +1,8 @@
 const { EventEmitter } = require('events')
+const { MissingSessionError } = require('./Errors')
 
 module.exports = function (io, sessionStore, cookieParser, cookieName) {
-  const missingSessionError = new Error('could not look up session by key')
+  const missingSessionError = new MissingSessionError()
 
   const sessionSockets = new EventEmitter()
   function next(error, socket, session) {

From a8c51de5105307bb19c8ffc2a8edbfbde6053ae3 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:50:35 +0100
Subject: [PATCH 06/14] [AuthorizationManager] use a new NotAuthorizedError

---
 services/real-time/app/js/AuthorizationManager.js | 6 ++++--
 services/real-time/app/js/Errors.js               | 7 +++++++
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/services/real-time/app/js/AuthorizationManager.js b/services/real-time/app/js/AuthorizationManager.js
index a545594479..0c37ac1423 100644
--- a/services/real-time/app/js/AuthorizationManager.js
+++ b/services/real-time/app/js/AuthorizationManager.js
@@ -1,6 +1,8 @@
 /* eslint-disable
     camelcase,
 */
+const { NotAuthorizedError } = require('./Errors')
+
 let AuthorizationManager
 module.exports = AuthorizationManager = {
   assertClientCanViewProject(client, callback) {
@@ -23,7 +25,7 @@ module.exports = AuthorizationManager = {
     if (allowedLevels.includes(client.ol_context.privilege_level)) {
       callback(null)
     } else {
-      callback(new Error('not authorized'))
+      callback(new NotAuthorizedError())
     }
   },
 
@@ -49,7 +51,7 @@ module.exports = AuthorizationManager = {
     if (client.ol_context[`doc:${doc_id}`] === 'allowed') {
       callback(null)
     } else {
-      callback(new Error('not authorized'))
+      callback(new NotAuthorizedError())
     }
   },
 
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 7a039c54c1..57190b75e5 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -21,6 +21,12 @@ class MissingSessionError extends OError {
   }
 }
 
+class NotAuthorizedError extends OError {
+  constructor() {
+    super('not authorized')
+  }
+}
+
 class NullBytesInOpError extends OError {
   constructor(jsonChange) {
     super('null bytes found in op', { jsonChange })
@@ -37,6 +43,7 @@ module.exports = {
   CodedError,
   DataTooLargeToParseError,
   MissingSessionError,
+  NotAuthorizedError,
   NullBytesInOpError,
   UpdateTooLargeError
 }

From 59c4c884a5a84e8eca772b787e85c710876d9e78 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 11:50:43 +0100
Subject: [PATCH 07/14] [WebsocketController] use the new NotAuthorizedError

---
 services/real-time/app/js/WebsocketController.js | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/services/real-time/app/js/WebsocketController.js b/services/real-time/app/js/WebsocketController.js
index a0c33f5cbe..a695d02b96 100644
--- a/services/real-time/app/js/WebsocketController.js
+++ b/services/real-time/app/js/WebsocketController.js
@@ -9,6 +9,7 @@ const DocumentUpdaterManager = require('./DocumentUpdaterManager')
 const ConnectedUsersManager = require('./ConnectedUsersManager')
 const WebsocketLoadBalancer = require('./WebsocketLoadBalancer')
 const RoomManager = require('./RoomManager')
+const { NotAuthorizedError } = require('./Errors')
 
 let WebsocketController
 module.exports = WebsocketController = {
@@ -48,12 +49,7 @@ module.exports = WebsocketController = {
       }
 
       if (!privilegeLevel) {
-        const err = new Error('not authorized')
-        logger.warn(
-          { err, project_id, user_id, client_id: client.id },
-          'user is not authorized to join project'
-        )
-        return callback(err)
+        return callback(new NotAuthorizedError())
       }
 
       client.ol_context = {}

From 68bc9d0d23ccc7c2580d1ede900b1c45e0f75677 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 12:03:54 +0100
Subject: [PATCH 08/14] [WebApiManager] use a new WebApiRequestFailedError

---
 services/real-time/app/js/Errors.js                   | 9 ++++++++-
 services/real-time/app/js/WebApiManager.js            | 8 ++------
 services/real-time/test/unit/js/WebApiManagerTests.js | 5 ++++-
 3 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 57190b75e5..5b41334fb3 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -39,11 +39,18 @@ class UpdateTooLargeError extends OError {
   }
 }
 
+class WebApiRequestFailedError extends OError {
+  constructor(statusCode) {
+    super('non-success status code from web', { statusCode })
+  }
+}
+
 module.exports = {
   CodedError,
   DataTooLargeToParseError,
   MissingSessionError,
   NotAuthorizedError,
   NullBytesInOpError,
-  UpdateTooLargeError
+  UpdateTooLargeError,
+  WebApiRequestFailedError
 }
diff --git a/services/real-time/app/js/WebApiManager.js b/services/real-time/app/js/WebApiManager.js
index 62020a98ab..dffcca51c8 100644
--- a/services/real-time/app/js/WebApiManager.js
+++ b/services/real-time/app/js/WebApiManager.js
@@ -4,7 +4,7 @@
 const request = require('request')
 const settings = require('settings-sharelatex')
 const logger = require('logger-sharelatex')
-const { CodedError } = require('./Errors')
+const { CodedError, WebApiRequestFailedError } = require('./Errors')
 
 module.exports = {
   joinProject(project_id, user, callback) {
@@ -57,11 +57,7 @@ module.exports = {
             )
           )
         } else {
-          err = new Error(
-            `non-success status code from web: ${response.statusCode}`
-          )
-          logger.error({ err, project_id, user_id }, 'error accessing web api')
-          callback(err)
+          callback(new WebApiRequestFailedError(response.statusCode))
         }
       }
     )
diff --git a/services/real-time/test/unit/js/WebApiManagerTests.js b/services/real-time/test/unit/js/WebApiManagerTests.js
index 52c6da137a..4435bc14f9 100644
--- a/services/real-time/test/unit/js/WebApiManagerTests.js
+++ b/services/real-time/test/unit/js/WebApiManagerTests.js
@@ -106,7 +106,10 @@ describe('WebApiManager', function () {
       return it('should call the callback with an error', function () {
         return this.callback
           .calledWith(
-            sinon.match({ message: 'non-success status code from web: 500' })
+            sinon.match({
+              message: 'non-success status code from web',
+              info: { statusCode: 500 }
+            })
           )
           .should.equal(true)
       })

From 02a23822647433906731501b41bd9fa310c9adba Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 12:14:02 +0100
Subject: [PATCH 09/14] [WebApiManager] use a new
 CorruptedJoinProjectResponseError

---
 services/real-time/app/js/Errors.js        |  7 +++++++
 services/real-time/app/js/WebApiManager.js | 14 ++++++--------
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 5b41334fb3..ebcf1d1d81 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -6,6 +6,12 @@ class CodedError extends OError {
   }
 }
 
+class CorruptedJoinProjectResponseError extends OError {
+  constructor() {
+    super('no data returned from joinProject request')
+  }
+}
+
 class DataTooLargeToParseError extends OError {
   constructor(data) {
     super('data too large to parse', {
@@ -47,6 +53,7 @@ class WebApiRequestFailedError extends OError {
 
 module.exports = {
   CodedError,
+  CorruptedJoinProjectResponseError,
   DataTooLargeToParseError,
   MissingSessionError,
   NotAuthorizedError,
diff --git a/services/real-time/app/js/WebApiManager.js b/services/real-time/app/js/WebApiManager.js
index dffcca51c8..a39d9dd832 100644
--- a/services/real-time/app/js/WebApiManager.js
+++ b/services/real-time/app/js/WebApiManager.js
@@ -4,7 +4,11 @@
 const request = require('request')
 const settings = require('settings-sharelatex')
 const logger = require('logger-sharelatex')
-const { CodedError, WebApiRequestFailedError } = require('./Errors')
+const {
+  CodedError,
+  CorruptedJoinProjectResponseError,
+  WebApiRequestFailedError
+} = require('./Errors')
 
 module.exports = {
   joinProject(project_id, user, callback) {
@@ -32,15 +36,9 @@ module.exports = {
         if (error) {
           return callback(error)
         }
-        let err
         if (response.statusCode >= 200 && response.statusCode < 300) {
           if (!(data && data.project)) {
-            err = new Error('no data returned from joinProject request')
-            logger.error(
-              { err, project_id, user_id },
-              'error accessing web api'
-            )
-            return callback(err)
+            return callback(new CorruptedJoinProjectResponseError())
           }
           callback(
             null,

From 8abfdb87ff48d59fe3fe71d95d9fd6b1dd5ce721 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 12:52:59 +0100
Subject: [PATCH 10/14] [DocumentUpdaterManager] use a new
 DocumentUpdaterRequestFailedError

---
 .../app/js/DocumentUpdaterManager.js          | 29 +++++++--------
 services/real-time/app/js/Errors.js           | 10 ++++++
 .../unit/js/DocumentUpdaterManagerTests.js    | 36 ++++++++++++-------
 3 files changed, 45 insertions(+), 30 deletions(-)

diff --git a/services/real-time/app/js/DocumentUpdaterManager.js b/services/real-time/app/js/DocumentUpdaterManager.js
index 167bb000a4..1b99ed7ab4 100644
--- a/services/real-time/app/js/DocumentUpdaterManager.js
+++ b/services/real-time/app/js/DocumentUpdaterManager.js
@@ -6,7 +6,11 @@ const _ = require('underscore')
 const logger = require('logger-sharelatex')
 const settings = require('settings-sharelatex')
 const metrics = require('metrics-sharelatex')
-const { NullBytesInOpError, UpdateTooLargeError } = require('./Errors')
+const {
+  DocumentUpdaterRequestFailedError,
+  NullBytesInOpError,
+  UpdateTooLargeError
+} = require('./Errors')
 
 const rclient = require('redis-sharelatex').createClient(
   settings.redis.documentupdater
@@ -51,15 +55,9 @@ const DocumentUpdaterManager = {
         )
         callback(err)
       } else {
-        err = new Error(
-          `doc updater returned a non-success status code: ${res.statusCode}`
+        callback(
+          new DocumentUpdaterRequestFailedError('getDocument', res.statusCode)
         )
-        err.statusCode = res.statusCode
-        logger.error(
-          { err, project_id, doc_id, url },
-          `doc updater returned a non-success status code: ${res.statusCode}`
-        )
-        callback(err)
       }
     })
   },
@@ -89,15 +87,12 @@ const DocumentUpdaterManager = {
         logger.log({ project_id }, 'deleted project from document updater')
         callback(null)
       } else {
-        err = new Error(
-          `document updater returned a failure status code: ${res.statusCode}`
+        callback(
+          new DocumentUpdaterRequestFailedError(
+            'flushProjectToMongoAndDelete',
+            res.statusCode
+          )
         )
-        err.statusCode = res.statusCode
-        logger.error(
-          { err, project_id },
-          `document updater returned failure status code: ${res.statusCode}`
-        )
-        callback(err)
       }
     })
   },
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index ebcf1d1d81..1e6ffbd4ef 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -21,6 +21,15 @@ class DataTooLargeToParseError extends OError {
   }
 }
 
+class DocumentUpdaterRequestFailedError extends OError {
+  constructor(action, statusCode) {
+    super('doc updater returned a non-success status code', {
+      action,
+      statusCode
+    })
+  }
+}
+
 class MissingSessionError extends OError {
   constructor() {
     super('could not look up session by key')
@@ -55,6 +64,7 @@ module.exports = {
   CodedError,
   CorruptedJoinProjectResponseError,
   DataTooLargeToParseError,
+  DocumentUpdaterRequestFailedError,
   MissingSessionError,
   NotAuthorizedError,
   NullBytesInOpError,
diff --git a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
index 2ded504051..f5023b3e30 100644
--- a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
+++ b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
@@ -163,13 +163,18 @@ describe('DocumentUpdaterManager', function () {
 
       return it('should return the callback with an error', function () {
         this.callback.called.should.equal(true)
-        const err = this.callback.getCall(0).args[0]
-        err.should.have.property('statusCode', 500)
-        err.should.have.property(
-          'message',
-          'doc updater returned a non-success status code: 500'
-        )
-        return this.logger.error.called.should.equal(true)
+        this.callback
+          .calledWith(
+            sinon.match({
+              message: 'doc updater returned a non-success status code',
+              info: {
+                action: 'getDocument',
+                statusCode: 500
+              }
+            })
+          )
+          .should.equal(true)
+        this.logger.error.called.should.equal(false)
       })
     })
   })
@@ -234,12 +239,17 @@ describe('DocumentUpdaterManager', function () {
 
       return it('should return the callback with an error', function () {
         this.callback.called.should.equal(true)
-        const err = this.callback.getCall(0).args[0]
-        err.should.have.property('statusCode', 500)
-        return err.should.have.property(
-          'message',
-          'document updater returned a failure status code: 500'
-        )
+        this.callback
+          .calledWith(
+            sinon.match({
+              message: 'doc updater returned a non-success status code',
+              info: {
+                action: 'flushProjectToMongoAndDelete',
+                statusCode: 500
+              }
+            })
+          )
+          .should.equal(true)
       })
     })
   })

From 4cb8cc4a85935031de4c3bf5922247e2e46ae3f7 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 12:59:52 +0100
Subject: [PATCH 11/14] [DocumentUpdaterManager] use a new
 ClientRequestedMissingOpsError

---
 .../real-time/app/js/DocumentUpdaterManager.js   |  9 ++-------
 services/real-time/app/js/Errors.js              |  9 +++++++++
 .../test/unit/js/DocumentUpdaterManagerTests.js  | 16 +++++++++-------
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/services/real-time/app/js/DocumentUpdaterManager.js b/services/real-time/app/js/DocumentUpdaterManager.js
index 1b99ed7ab4..67ecd82c29 100644
--- a/services/real-time/app/js/DocumentUpdaterManager.js
+++ b/services/real-time/app/js/DocumentUpdaterManager.js
@@ -7,6 +7,7 @@ const logger = require('logger-sharelatex')
 const settings = require('settings-sharelatex')
 const metrics = require('metrics-sharelatex')
 const {
+  ClientRequestedMissingOpsError,
   DocumentUpdaterRequestFailedError,
   NullBytesInOpError,
   UpdateTooLargeError
@@ -47,13 +48,7 @@ const DocumentUpdaterManager = {
         body = body || {}
         callback(null, body.lines, body.version, body.ranges, body.ops)
       } else if ([404, 422].includes(res.statusCode)) {
-        err = new Error('doc updater could not load requested ops')
-        err.statusCode = res.statusCode
-        logger.warn(
-          { err, project_id, doc_id, url, fromVersion },
-          'doc updater could not load requested ops'
-        )
-        callback(err)
+        callback(new ClientRequestedMissingOpsError(res.statusCode))
       } else {
         callback(
           new DocumentUpdaterRequestFailedError('getDocument', res.statusCode)
diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 1e6ffbd4ef..24c0b3d316 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -1,5 +1,13 @@
 const OError = require('@overleaf/o-error')
 
+class ClientRequestedMissingOpsError extends OError {
+  constructor(statusCode) {
+    super('doc updater could not load requested ops', {
+      statusCode
+    })
+  }
+}
+
 class CodedError extends OError {
   constructor(message, code) {
     super(message, { code })
@@ -63,6 +71,7 @@ class WebApiRequestFailedError extends OError {
 module.exports = {
   CodedError,
   CorruptedJoinProjectResponseError,
+  ClientRequestedMissingOpsError,
   DataTooLargeToParseError,
   DocumentUpdaterRequestFailedError,
   MissingSessionError,
diff --git a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
index f5023b3e30..828f516364 100644
--- a/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
+++ b/services/real-time/test/unit/js/DocumentUpdaterManagerTests.js
@@ -136,14 +136,16 @@ describe('DocumentUpdaterManager', function () {
 
         return it('should return the callback with an error', function () {
           this.callback.called.should.equal(true)
-          const err = this.callback.getCall(0).args[0]
-          err.should.have.property('statusCode', statusCode)
-          err.should.have.property(
-            'message',
-            'doc updater could not load requested ops'
-          )
+          this.callback
+            .calledWith(
+              sinon.match({
+                message: 'doc updater could not load requested ops',
+                info: { statusCode }
+              })
+            )
+            .should.equal(true)
           this.logger.error.called.should.equal(false)
-          return this.logger.warn.called.should.equal(true)
+          this.logger.warn.called.should.equal(false)
         })
       })
     )

From 0462e3e4371156e7ebd7db940141406475764ac0 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 13:07:27 +0100
Subject: [PATCH 12/14] [WebsocketController] use a new NotJoinedError

---
 services/real-time/app/js/Errors.js              | 7 +++++++
 services/real-time/app/js/WebsocketController.js | 8 ++++----
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index 24c0b3d316..d684764b0c 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -50,6 +50,12 @@ class NotAuthorizedError extends OError {
   }
 }
 
+class NotJoinedError extends OError {
+  constructor() {
+    super('no project_id found on client')
+  }
+}
+
 class NullBytesInOpError extends OError {
   constructor(jsonChange) {
     super('null bytes found in op', { jsonChange })
@@ -76,6 +82,7 @@ module.exports = {
   DocumentUpdaterRequestFailedError,
   MissingSessionError,
   NotAuthorizedError,
+  NotJoinedError,
   NullBytesInOpError,
   UpdateTooLargeError,
   WebApiRequestFailedError
diff --git a/services/real-time/app/js/WebsocketController.js b/services/real-time/app/js/WebsocketController.js
index a695d02b96..b099d8e4e4 100644
--- a/services/real-time/app/js/WebsocketController.js
+++ b/services/real-time/app/js/WebsocketController.js
@@ -9,7 +9,7 @@ const DocumentUpdaterManager = require('./DocumentUpdaterManager')
 const ConnectedUsersManager = require('./ConnectedUsersManager')
 const WebsocketLoadBalancer = require('./WebsocketLoadBalancer')
 const RoomManager = require('./RoomManager')
-const { NotAuthorizedError } = require('./Errors')
+const { NotAuthorizedError, NotJoinedError } = require('./Errors')
 
 let WebsocketController
 module.exports = WebsocketController = {
@@ -158,7 +158,7 @@ module.exports = WebsocketController = {
     metrics.inc('editor.join-doc')
     const { project_id, user_id, is_restricted_user } = client.ol_context
     if (!project_id) {
-      return callback(new Error('no project_id found on client'))
+      return callback(new NotJoinedError())
     }
     logger.log(
       { user_id, project_id, doc_id, fromVersion, client_id: client.id },
@@ -424,7 +424,7 @@ module.exports = WebsocketController = {
       return callback(null, [])
     }
     if (!project_id) {
-      return callback(new Error('no project_id found on client'))
+      return callback(new NotJoinedError())
     }
     logger.log(
       { user_id, project_id, client_id: client.id },
@@ -459,7 +459,7 @@ module.exports = WebsocketController = {
     // client may have disconnected, but we can submit their update to doc-updater anyways.
     const { user_id, project_id } = client.ol_context
     if (!project_id) {
-      return callback(new Error('no project_id found on client'))
+      return callback(new NotJoinedError())
     }
 
     WebsocketController._assertClientCanApplyUpdate(

From 50140f785a2fbfb5e78b524b5261db95994e931a Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 13:10:22 +0100
Subject: [PATCH 13/14] [WebsocketController] use a new
 JoinLeaveEpochMismatchError

---
 services/real-time/app/js/Errors.js              | 7 +++++++
 services/real-time/app/js/WebsocketController.js | 8 ++++++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index d684764b0c..c5c082bfac 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -38,6 +38,12 @@ class DocumentUpdaterRequestFailedError extends OError {
   }
 }
 
+class JoinLeaveEpochMismatchError extends OError {
+  constructor() {
+    super('joinLeaveEpoch mismatch')
+  }
+}
+
 class MissingSessionError extends OError {
   constructor() {
     super('could not look up session by key')
@@ -80,6 +86,7 @@ module.exports = {
   ClientRequestedMissingOpsError,
   DataTooLargeToParseError,
   DocumentUpdaterRequestFailedError,
+  JoinLeaveEpochMismatchError,
   MissingSessionError,
   NotAuthorizedError,
   NotJoinedError,
diff --git a/services/real-time/app/js/WebsocketController.js b/services/real-time/app/js/WebsocketController.js
index b099d8e4e4..a443a49f95 100644
--- a/services/real-time/app/js/WebsocketController.js
+++ b/services/real-time/app/js/WebsocketController.js
@@ -9,7 +9,11 @@ const DocumentUpdaterManager = require('./DocumentUpdaterManager')
 const ConnectedUsersManager = require('./ConnectedUsersManager')
 const WebsocketLoadBalancer = require('./WebsocketLoadBalancer')
 const RoomManager = require('./RoomManager')
-const { NotAuthorizedError, NotJoinedError } = require('./Errors')
+const {
+  JoinLeaveEpochMismatchError,
+  NotAuthorizedError,
+  NotJoinedError
+} = require('./Errors')
 
 let WebsocketController
 module.exports = WebsocketController = {
@@ -180,7 +184,7 @@ module.exports = WebsocketController = {
       }
       if (joinLeaveEpoch !== client.joinLeaveEpoch) {
         // another joinDoc or leaveDoc rpc overtook us
-        return callback(new Error('joinLeaveEpoch mismatch'))
+        return callback(new JoinLeaveEpochMismatchError())
       }
       // ensure the per-doc applied-ops channel is subscribed before sending the
       // doc to the client, so that no events are missed.

From 880056d397137c26b5769c45ecfff6a6d9ba7e59 Mon Sep 17 00:00:00 2001
From: Jakob Ackermann <jakob.ackermann@overleaf.com>
Date: Thu, 20 Aug 2020 13:12:56 +0100
Subject: [PATCH 14/14] [Router] use a new UnexpectedArgumentsError

---
 services/real-time/app/js/Errors.js | 7 +++++++
 services/real-time/app/js/Router.js | 3 ++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/services/real-time/app/js/Errors.js b/services/real-time/app/js/Errors.js
index c5c082bfac..562c9888ab 100644
--- a/services/real-time/app/js/Errors.js
+++ b/services/real-time/app/js/Errors.js
@@ -68,6 +68,12 @@ class NullBytesInOpError extends OError {
   }
 }
 
+class UnexpectedArgumentsError extends OError {
+  constructor() {
+    super('unexpected arguments')
+  }
+}
+
 class UpdateTooLargeError extends OError {
   constructor(updateSize) {
     super('update is too large', { updateSize })
@@ -91,6 +97,7 @@ module.exports = {
   NotAuthorizedError,
   NotJoinedError,
   NullBytesInOpError,
+  UnexpectedArgumentsError,
   UpdateTooLargeError,
   WebApiRequestFailedError
 }
diff --git a/services/real-time/app/js/Router.js b/services/real-time/app/js/Router.js
index 87c1991d4c..5e0ae4bf76 100644
--- a/services/real-time/app/js/Router.js
+++ b/services/real-time/app/js/Router.js
@@ -9,6 +9,7 @@ const HttpController = require('./HttpController')
 const HttpApiController = require('./HttpApiController')
 const bodyParser = require('body-parser')
 const base64id = require('base64id')
+const { UnexpectedArgumentsError } = require('./Errors')
 
 const basicAuth = require('basic-auth-connect')
 const httpAuth = basicAuth(function (user, pass) {
@@ -64,7 +65,7 @@ module.exports = Router = {
   },
 
   _handleInvalidArguments(client, method, args) {
-    const error = new Error('unexpected arguments')
+    const error = new UnexpectedArgumentsError()
     let callback = args[args.length - 1]
     if (typeof callback !== 'function') {
       callback = function () {}