Summarise updates when returning them

services/track-changes/app/coffee/HttpController.coffee

@@ -40,12 +40,40 @@ module.exports = HttpController =
 
 		UpdatesManager.getUpdatesWithUserInfo doc_id, to: to, limit: limit, (error, updates) ->
 			return next(error) if error?
-			formattedUpdates = for update in updates
-				{
-					meta: update.meta
-					v: update.v
-				}
-			res.send JSON.stringify updates: formattedUpdates
+			res.send JSON.stringify updates: HttpController._buildUpdatesView(updates)
+
+	TIME_BETWEEN_DISTINCT_UPDATES: fiveMinutes = 5 * 60 * 1000
+	_buildUpdatesView: (updates) ->
+		view = []
+		for update in updates.slice().reverse()
+			lastUpdate = view[view.length - 1]
+			if lastUpdate and update.meta.start_ts - lastUpdate.meta.end_ts < @TIME_BETWEEN_DISTINCT_UPDATES
+				if update.meta.user?
+					userExists = false
+					for user in lastUpdate.meta.users
+						if user.id == update.meta.user.id
+							userExists = true
+							break
+					if !userExists
+						lastUpdate.meta.users.push update.meta.user
+				lastUpdate.meta.start_ts = Math.min(lastUpdate.meta.start_ts, update.meta.start_ts)
+				lastUpdate.meta.end_ts   = Math.max(lastUpdate.meta.end_ts, update.meta.end_ts)
+				lastUpdate.toV = update.v
+			else
+				newUpdate =
+					meta:
+						users: []
+						start_ts: update.meta.start_ts
+						end_ts: update.meta.end_ts
+					fromV: update.v
+					toV: update.v
+
+				if update.meta.user?
+					newUpdate.meta.users.push update.meta.user
+
+				view.push newUpdate
+
+		return view.reverse()
 
 	restore: (req, res, next = (error) ->) ->
 		{doc_id, project_id, version} = req.params

services/track-changes/test/acceptance/coffee/GettingUpdatesTests.coffee

@@ -11,12 +11,10 @@ TrackChangesClient = require "./helpers/TrackChangesClient"
 MockWebApi = require "./helpers/MockWebApi"
 
 describe "Getting updates", ->
-	before (done) ->
+	before ->
 		@now = Date.now()
 		@to = @now
 		@user_id = ObjectId().toString()
-		@doc_id = ObjectId().toString()
-		@project_id = ObjectId().toString()
 
 		@minutes = 60 * 1000
 
@@ -27,49 +25,87 @@ describe "Getting updates", ->
 			id: @user_id
 		sinon.spy MockWebApi, "getUser"
 
-		@updates = [{
-			op: [{ i: "one ", p: 0 }]
-			meta: { ts: @to - 4 * @minutes, user_id: @user_id }
-			v: 3
-		}, {
-			op: [{ i: "two ", p: 4 }]
-			meta: { ts: @to - 2 * @minutes }
-			v: 4
-		}, {
-			op: [{ i: "three ", p: 8 }]
-			meta: { ts: @to, user_id: @user_id }
-			v: @toVersion = 5
-		}, {
-			op: [{ i: "four", p: 14 }]
-			meta: { ts: @to + 2 * @minutes, user_id: @user_id }
-			v: 6
-		}]
-
-		TrackChangesClient.pushRawUpdates @doc_id, @updates, (error) =>
-			throw error if error?
-			TrackChangesClient.getUpdates @project_id, @doc_id, { to: @toVersion, limit: 2 }, (error, body) =>
-				throw error if error?
-				@updates = body.updates
-				done()
-
 	after: () ->
 		MockWebApi.getUser.restore()
 
-	it "should fetch the user details from the web api", ->
-		MockWebApi.getUser
-			.calledWith(@user_id)
-			.should.equal true
+	describe "getting updates in the middle", ->
+		before (done) ->
+			@doc_id = ObjectId().toString()
+			@project_id = ObjectId().toString()
+			@updates = [{
+				op: [{ i: "one ", p: 0 }]
+				meta: { ts: @to - 20 * @minutes, user_id: @user_id }
+				v: 3
+			}, {
+				op: [{ i: "two ", p: 4 }]
+				meta: { ts: @to - 10 * @minutes }
+				v: 4
+			}, {
+				op: [{ i: "three ", p: 8 }]
+				meta: { ts: @to, user_id: @user_id }
+				v: @toVersion = 5
+			}, {
+				op: [{ i: "four", p: 14 }]
+				meta: { ts: @to + 2 * @minutes, user_id: @user_id }
+				v: 6
+			}]
 
-	it "should return the updates", ->
-		expect(@updates).to.deep.equal [{
-			meta:
-				start_ts: @to
-				end_ts: @to
-				user: @user
-			v: 5
-		}, {
-			meta:
-				start_ts: @to - 2 * @minutes
-				end_ts: @to - 2 * @minutes
-			v: 4
-		}]
+			TrackChangesClient.pushRawUpdates @doc_id, @updates, (error) =>
+				throw error if error?
+				TrackChangesClient.getUpdates @project_id, @doc_id, { to: @toVersion, limit: 2 }, (error, body) =>
+					throw error if error?
+					@updates = body.updates
+					done()
+
+		it "should fetch the user details from the web api", ->
+			MockWebApi.getUser
+				.calledWith(@user_id)
+				.should.equal true
+
+		it "should return the updates", ->
+			expect(@updates).to.deep.equal [{
+				meta:
+					start_ts: @to
+					end_ts: @to
+					users: [@user]
+				fromV: 5
+				toV: 5
+			}, {
+				meta:
+					users: []
+					start_ts: @to - 10 * @minutes
+					end_ts: @to - 10 * @minutes
+				toV: 4
+				fromV: 4
+			}]
+
+	describe "getting updates that should be combined", ->
+		before (done) ->
+			@doc_id = ObjectId().toString()
+			@project_id = ObjectId().toString()
+			@updates = [{
+				op: [{ i: "two ", p: 4 }]
+				meta: { ts: @to - 2 * @minutes, user_id: @user_id }
+				v: 4
+			}, {
+				op: [{ i: "three ", p: 8 }]
+				meta: { ts: @to, user_id: @user_id }
+				v: @toVersion = 5
+			}]
+
+			TrackChangesClient.pushRawUpdates @doc_id, @updates, (error) =>
+				throw error if error?
+				TrackChangesClient.getUpdates @project_id, @doc_id, { to: @toVersion, limit: 2 }, (error, body) =>
+					throw error if error?
+					@updates = body.updates
+					done()
+
+		it "should return the updates", ->
+			expect(@updates).to.deep.equal [{
+				meta:
+					start_ts: @to - 2 * @minutes
+					end_ts: @to
+					users: [@user]
+				fromV: 4
+				toV: 5
+			}]

services/track-changes/test/unit/coffee/HttpController/HttpControllerTests.coffee

@@ -16,6 +16,7 @@ describe "HttpController", ->
 		@project_id = "project-id-123"
 		@next = sinon.stub()
 		@user_id = "mock-user-123"
+		@now = Date.now()
 
 	describe "flushUpdatesWithLock", ->
 		beforeEach ->
@@ -73,12 +74,9 @@ describe "HttpController", ->
 					limit: @limit.toString()
 			@res =
 				send: sinon.stub()
-			@rawUpdates = [{
-				v:      @v    = 42
-				op:     @op   = "mock-op"
-				meta:   @meta = "mock-meta"
-				doc_id: @doc_id
-			}]
+			@rawUpdates = ["raw-updates"]
+			@updatesView = ["updates-view"]
+			@HttpController._buildUpdatesView = sinon.stub().returns(@updatesView)
 			@UpdatesManager.getUpdatesWithUserInfo = sinon.stub().callsArgWith(2, null, @rawUpdates)
 			@HttpController.getUpdates @req, @res, @next
 
@@ -87,13 +85,66 @@ describe "HttpController", ->
 				.calledWith(@doc_id, to: @to, limit: @limit)
 				.should.equal true
 
+		it "should build the updates view", ->
+			@HttpController._buildUpdatesView
+				.calledWith(@rawUpdates)
+				.should.equal true
+
 		it "should return the formatted updates", ->
-			updates = for update in @rawUpdates
-				{
-					meta: @meta
-					v:    @v
-				}
-			@res.send.calledWith(JSON.stringify(updates: updates)).should.equal true
+			@res.send.calledWith(JSON.stringify(updates: @updatesView)).should.equal true
+
+	describe "_buildUpdatesView", ->
+		it "should concat updates that are close in time", ->
+			expect(@HttpController._buildUpdatesView [{
+				meta:
+					user: @user_2 = { id: "mock-user-2" }
+					start_ts: @now + 20
+					end_ts:   @now + 30
+				v: 5
+			}, {
+				meta:
+					user: @user_1 = { id: "mock-user-1" }
+					start_ts: @now
+					end_ts:   @now + 10
+				v: 4
+			}]).to.deep.equal [{
+				meta:
+					users: [@user_1, @user_2]
+					start_ts: @now
+					end_ts:   @now + 30
+				fromV: 4
+				toV:   5
+			}]
+
+		it "should leave updates that are far apart in time", ->
+			oneDay = 1000 * 60 * 60 * 24
+			expect(@HttpController._buildUpdatesView [{
+				meta:
+					user: @user_2 = { id: "mock-user-2" }
+					start_ts: @now + oneDay
+					end_ts:   @now + oneDay + 10
+				v: 5
+			}, {
+				meta:
+					user: @user_1 = { id: "mock-user-2" }
+					start_ts: @now
+					end_ts:   @now + 10
+				v: 4
+			}]).to.deep.equal [{
+				meta:
+					users: [@user_2]
+					start_ts: @now + oneDay
+					end_ts:   @now + oneDay + 10
+				fromV: 5
+				toV: 5
+			}, {
+				meta:
+					users: [@user_1]
+					start_ts: @now
+					end_ts:   @now + 10
+				fromV: 4
+				toV: 4
+			}]
 
 	describe "RestoreManager", ->
 		beforeEach ->