Add in proxy to track changes api

services/web/app/coffee/Features/TrackChanges/TrackChangesController.coffee

@@ -0,0 +1,13 @@
+logger = require "logger-sharelatex"
+request = require "request"
+settings = require "settings-sharelatex"
+
+module.exports = TrackChangesController =
+	proxyToTrackChangesApi: (req, res, next = (error) ->) ->
+		url = settings.apis.trackchanges.url + req.url
+		logger.log url: url, "proxying to track-changes api"
+		getReq = request.get(url)
+		getReq.pipe(res)
+		getReq.on "error", (error) ->
+			logger.error err: error, "track-changes API error"
+			next(error)

services/web/app/coffee/router.coffee

@@ -32,6 +32,7 @@ CompileController = require("./Features/Compile/CompileController")
 HealthCheckController = require("./Features/HealthCheck/HealthCheckController")
 ProjectDownloadsController = require "./Features/Downloads/ProjectDownloadsController"
 FileStoreController = require("./Features/FileStore/FileStoreController")
+TrackChangesController = require("./Features/TrackChanges/TrackChangesController")
 logger = require("logger-sharelatex")
 
 httpAuth = require('express').basicAuth (user, pass)->
@@ -122,6 +123,9 @@ module.exports = class Router
 		app.get  '/Project/:Project_id/version', SecutiryManager.requestCanAccessProject, versioningController.listVersions
 		app.get  '/Project/:Project_id/version/:Version_id', SecutiryManager.requestCanAccessProject, versioningController.getVersion
 
+		app.get  "/project/:Project_id/doc/:doc_id/updates", SecutiryManager.requestCanAccessProject, TrackChangesController.proxyToTrackChangesApi
+		app.get  "/project/:Project_id/doc/:doc_id/diff", SecutiryManager.requestCanAccessProject, TrackChangesController.proxyToTrackChangesApi
+
 		app.post '/project/:project_id/leave', AuthenticationController.requireLogin(), CollaboratorsController.removeSelfFromProject
 		app.get  '/project/:Project_id/collaborators', SecutiryManager.requestCanAccessProject(allow_auth_token: true), CollaboratorsController.getCollaborators
 

services/web/test/UnitTests/coffee/TrackChanges/TrackChangesControllerTests.coffee

@@ -0,0 +1,46 @@
+chai = require('chai')
+chai.should()
+sinon = require("sinon")
+modulePath = "../../../../app/js/Features/TrackChanges/TrackChangesController"
+SandboxedModule = require('sandboxed-module')
+
+describe "TrackChangesController", ->
+	beforeEach ->
+		@TrackChangesController = SandboxedModule.require modulePath, requires:
+			"request" : @request = {}
+			"settings-sharelatex": @settings = {}
+			"logger-sharelatex": @logger = {log: sinon.stub(), error: sinon.stub()}
+
+	describe "proxyToTrackChangesApi", ->
+		beforeEach ->
+			@req = { url: "/mock/url" }
+			@res = "mock-res"
+			@next = sinon.stub()
+			@settings.apis =
+				trackchanges:
+					url: "http://trackchanges.example.com"
+			@proxy =
+				events: {}
+				pipe: sinon.stub()
+				on: (event, handler) -> @events[event] = handler
+			@request.get = sinon.stub().returns @proxy
+			@TrackChangesController.proxyToTrackChangesApi @req, @res, @next
+
+		describe "successfully", ->
+			it "should call the track changes api", ->
+				@request.get
+					.calledWith("#{@settings.apis.trackchanges.url}#{@req.url}")
+					.should.equal true
+
+			it "should pipe the response to the client", ->
+				@proxy.pipe
+					.calledWith(@res)
+					.should.equal true
+
+		describe "with an error", ->
+			beforeEach ->
+				@proxy.events["error"].call(@proxy, @error = new Error("oops"))
+
+			it "should pass the error up the call chain", ->
+				@next.calledWith(@error).should.equal true
+