mirror of
https://github.com/overleaf/overleaf.git
synced 2024-11-30 02:15:13 -05:00
57 lines
2.1 KiB
CoffeeScript
57 lines
2.1 KiB
CoffeeScript
|
logger = require "logger-sharelatex"
|
||
|
|
|
||
|
|
LockState = {} # locks for docker container operations, by container name
|
||
|
|
|
||
|
|
module.exports = LockManager =
|
||
|
|
|
||
|
|
MAX_LOCK_HOLD_TIME: 15000 # how long we can keep a lock
|
||
|
|
MAX_LOCK_WAIT_TIME: 10000 # how long we wait for a lock
|
||
|
|
LOCK_TEST_INTERVAL: 1000 # retry time
|
||
|
|
|
||
|
|
tryLock: (key, callback = (err, gotLock) ->) ->
|
||
|
|
existingLock = LockState[key]
|
||
|
|
if existingLock? # the lock is already taken, check how old it is
|
||
|
|
lockAge = Date.now() - existingLock.created
|
||
|
|
if lockAge < LockManager.MAX_LOCK_HOLD_TIME
|
||
|
|
return callback(null, false) # we didn't get the lock, bail out
|
||
|
|
else
|
||
|
|
logger.error {key: key, lock: existingLock, age:lockAge}, "taking old lock by force"
|
||
|
|
# take the lock
|
||
|
|
LockState[key] = lockValue = {created: Date.now()}
|
||
|
|
callback(null, true, lockValue)
|
||
|
|
|
||
|
|
getLock: (key, callback = (error, lockValue) ->) ->
|
||
|
|
startTime = Date.now()
|
||
|
|
do attempt = () ->
|
||
|
|
LockManager.tryLock key, (error, gotLock, lockValue) ->
|
||
|
|
return callback(error) if error?
|
||
|
|
if gotLock
|
||
|
|
callback(null, lockValue)
|
||
|
|
else if Date.now() - startTime > LockManager.MAX_LOCK_WAIT_TIME
|
||
|
|
e = new Error("Lock timeout")
|
||
|
|
e.key = key
|
||
|
|
return callback(e)
|
||
|
|
else
|
||
|
|
setTimeout attempt, LockManager.LOCK_TEST_INTERVAL
|
||
|
|
|
||
|
|
releaseLock: (key, lockValue, callback = (error) ->) ->
|
||
|
|
existingLock = LockState[key]
|
||
|
|
if existingLock is lockValue # lockValue is an object, so we can test by reference
|
||
|
|
delete LockState[key] # our lock, so we can free it
|
||
|
|
callback()
|
||
|
|
else if existingLock? # lock exists but doesn't match ours
|
||
|
|
logger.error {key:key, lock: existingLock}, "tried to release lock taken by force"
|
||
|
|
callback()
|
||
|
|
else
|
||
|
|
logger.error {key:key, lock: existingLock}, "tried to release lock that has gone"
|
||
|
|
callback()
|
||
|
|
|
||
|
|
runWithLock: (key, runner = ( (releaseLock = (error) ->) -> ), callback = ( (error) -> )) ->
|
||
|
|
LockManager.getLock key, (error, lockValue) ->
|
||
|
|
return callback(error) if error?
|
||
|
|
runner (error1, args...) ->
|
||
|
|
LockManager.releaseLock key, lockValue, (error2) ->
|
||
|
|
error = error1 or error2
|
||
|
|
return callback(error) if error?
|
||
|
|
callback(null, args...)
|