overleaf/services/document-updater/app/coffee/ShareJsUpdateManager.coffee
2014-02-12 10:40:42 +00:00

68 lines
2.3 KiB
CoffeeScript

ShareJsModel = require "./sharejs/server/model"
ShareJsDB = require "./ShareJsDB"
async = require "async"
logger = require "logger-sharelatex"
Settings = require('settings-sharelatex')
Keys = require "./RedisKeyBuilder"
{EventEmitter} = require "events"
util = require "util"
redis = require('redis')
redisConf = Settings.redis?.web or Settings.redis or {host: "localhost", port: 6379}
rclient = redis.createClient(redisConf.port, redisConf.host)
rclient.auth(redisConf.password)
ShareJsModel:: = {}
util.inherits ShareJsModel, EventEmitter
module.exports = ShareJsUpdateManager =
getNewShareJsModel: () -> new ShareJsModel(ShareJsDB)
applyUpdates: (project_id, doc_id, updates, callback = (error, updatedDocLines) ->) ->
logger.log project_id: project_id, doc_id: doc_id, updates: updates, "applying sharejs updates"
jobs = []
# We could use a global model for all docs, but we're hitting issues with the
# internal state of ShareJS not being accessible for clearing caches, and
# getting stuck due to queued callbacks (line 260 of sharejs/server/model.coffee)
# This adds a small but hopefully acceptable overhead (~12ms per 1000 updates on
# my 2009 MBP).
model = @getNewShareJsModel()
@_listenForOps(model)
doc_key = Keys.combineProjectIdAndDocId(project_id, doc_id)
for update in updates
do (update) =>
jobs.push (callback) =>
model.applyOp doc_key, update, callback
async.series jobs, (error) =>
logger.log project_id: project_id, doc_id: doc_id, error: error, "applied updates"
if error?
@_sendError(project_id, doc_id, error)
return callback(error)
model.getSnapshot doc_key, (error, data) =>
if error?
@_sendError(project_id, doc_id, error)
return callback(error)
if typeof data.snapshot == "string"
docLines = data.snapshot.split("\n")
else
docLines = data.snapshot.lines
callback(null, docLines, data.v)
_listenForOps: (model) ->
model.on "applyOp", (doc_key, opData) ->
[project_id, doc_id] = Keys.splitProjectIdAndDocId(doc_key)
data = JSON.stringify
project_id: project_id
doc_id: doc_id
op: opData
rclient.publish "applied-ops", data
_sendError: (project_id, doc_id, error) ->
data = JSON.stringify
project_id: project_id
doc_id: doc_id
error: error.message || error
rclient.publish "applied-ops", data