add ability to resync project structure

services/document-updater/app.coffee

@@ -47,7 +47,8 @@ app.post   '/project/:project_id/doc/:doc_id',                          HttpCont
 app.post   '/project/:project_id/doc/:doc_id/flush',                    HttpController.flushDocIfLoaded
 app.delete '/project/:project_id/doc/:doc_id',                          HttpController.flushAndDeleteDoc
 app.delete '/project/:project_id',                                      HttpController.deleteProject
-app.post   '/project/:project_id',                   										HttpController.updateProject
+app.post   '/project/:project_id',                                      HttpController.updateProject
+app.post   '/project/:project_id/resync',                               HttpController.resyncProject
 app.post   '/project/:project_id/flush',                                HttpController.flushProject
 app.post   '/project/:project_id/doc/:doc_id/change/:change_id/accept', HttpController.acceptChanges
 app.post   '/project/:project_id/doc/:doc_id/change/accept',            HttpController.acceptChanges

services/document-updater/app/coffee/HistoryManager.coffee

@@ -2,6 +2,7 @@ Settings = require "settings-sharelatex"
 request  = require "request"
 logger = require "logger-sharelatex"
 HistoryRedisManager = require "./HistoryRedisManager"
+RedisManager = require "./RedisManager"
 
 module.exports = HistoryManager =
 	flushDocChangesAsync: (project_id, doc_id) ->
@@ -61,3 +62,14 @@ module.exports = HistoryManager =
 		prevBlock = Math.floor(previousLength / threshold)
 		newBlock  = Math.floor(length / threshold)
 		return newBlock != prevBlock
+
+	resyncProject: (project_id, docs, files, callback) ->
+		RedisManager.resyncProjectStructure project_id, docs, files, (error) ->
+			return callback(error) if error?
+			callback null
+
+			#jobs = _.union
+				#_.map docs, (doc) -> RedisManager.resyncDoc project_id, doc
+				#_.map files, (files) -> RedisManager.resyncFile project_id, file
+
+			#async.series jobs, callback

services/document-updater/app/coffee/HttpController.coffee

@@ -169,3 +169,11 @@ module.exports = HttpController =
 			return next(error) if error?
 			logger.log project_id: project_id, "updated project via http"
 			res.send 204 # No Content
+
+	resyncProject: (req, res, next = (error) ->) ->
+		project_id = req.params.project_id
+		{docs, files} = req.body
+
+		HistoryManager.resyncProject project_id, docs, files, (error) ->
+			return next(error) if error?
+			res.send 204

services/document-updater/app/coffee/RedisManager.coffee

@@ -321,6 +321,14 @@ module.exports = RedisManager =
 	getDocIdsInProject: (project_id, callback = (error, doc_ids) ->) ->
 		rclient.smembers keys.docsInProject(project_id: project_id), callback
 
+	resyncProjectStructure: (project_id, docs, files, callback) ->
+		update =
+			projectStructure: { docs, files }
+			meta:
+				ts: new Date()
+		jsonUpdate = JSON.stringify update
+		rclient.rpush projectHistoryKeys.projectHistoryOps({project_id}), jsonUpdate, callback
+
 	_serializeRanges: (ranges, callback = (error, serializedRanges) ->) ->
 		jsonRanges = JSON.stringify(ranges)
 		if jsonRanges? and jsonRanges.length > MAX_RANGES_SIZE