mirror of
https://github.com/overleaf/overleaf.git
synced 2024-11-29 23:04:15 -05:00
53 lines
1.7 KiB
CoffeeScript
53 lines
1.7 KiB
CoffeeScript
metrics = require('./Metrics')
|
|
Settings = require('settings-sharelatex')
|
|
redis = require("redis-sharelatex")
|
|
rclient = redis.createClient(Settings.redis.web)
|
|
keys = require('./RedisKeyBuilder')
|
|
logger = require "logger-sharelatex"
|
|
|
|
module.exports = LockManager =
|
|
LOCK_TEST_INTERVAL: 50 # 50ms between each test of the lock
|
|
MAX_LOCK_WAIT_TIME: 10000 # 10s maximum time to spend trying to get the lock
|
|
REDIS_LOCK_EXPIRY: 30 # seconds. Time until lock auto expires in redis.
|
|
|
|
tryLock : (doc_id, callback = (err, isFree)->)->
|
|
rclient.set keys.blockingKey(doc_id: doc_id), "locked", "EX", LockManager.REDIS_LOCK_EXPIRY, "NX", (err, gotLock)->
|
|
return callback(err) if err?
|
|
if gotLock == "OK"
|
|
metrics.inc "doc-not-blocking"
|
|
callback err, true
|
|
else
|
|
metrics.inc "doc-blocking"
|
|
logger.log doc_id: doc_id, redis_response: gotLock, "doc is locked"
|
|
callback err, false
|
|
|
|
getLock: (doc_id, callback = (error) ->) ->
|
|
startTime = Date.now()
|
|
do attempt = () ->
|
|
if Date.now() - startTime > LockManager.MAX_LOCK_WAIT_TIME
|
|
return callback(new Error("Timeout"))
|
|
|
|
LockManager.tryLock doc_id, (error, gotLock) ->
|
|
return callback(error) if error?
|
|
if gotLock
|
|
callback(null)
|
|
else
|
|
setTimeout attempt, LockManager.LOCK_TEST_INTERVAL
|
|
|
|
checkLock: (doc_id, callback = (err, isFree)->)->
|
|
multi = rclient.multi()
|
|
multi.exists keys.blockingKey(doc_id:doc_id)
|
|
multi.exec (err, replys)->
|
|
return callback(err) if err?
|
|
exists = parseInt replys[0]
|
|
if exists == 1
|
|
metrics.inc "doc-blocking"
|
|
callback err, false
|
|
else
|
|
metrics.inc "doc-not-blocking"
|
|
callback err, true
|
|
|
|
releaseLock: (doc_id, callback)->
|
|
rclient.del keys.blockingKey(doc_id:doc_id), callback
|
|
|
|
|