Package net.javacrumbs.shedlock.provider.mongo

Class MongoLockProvider

java.lang.Object
net.javacrumbs.shedlock.provider.mongo.MongoLockProvider
All Implemented Interfaces:
LockProvider
public class MongoLockProvider
extends Object
implements LockProvider
Distributed lock using MongoDB >= 2.6. Requires mongo-java-driver > 3.4.0

It uses a collection that contains documents like this: 

 {
    "_id" : "lock name",
    "lockUntil" : ISODate("2017-01-07T16:52:04.071Z"),
    "lockedAt" : ISODate("2017-01-07T16:52:03.932Z"),
    "lockedBy" : "host name"
 }
lockedAt and lockedBy are just for troubleshooting and are not read by the code
  1. Attempts to insert a new lock record. As an optimization, we keep in-memory track of created lock records. If the record has been inserted, returns lock.
  2. We will try to update lock record using filter _id == name AND lock_until <= now
  3. If the update succeeded (1 updated document), we have the lock. If the update failed (0 updated documents) somebody else holds the lock
  4. When unlocking, lock_until is set to now.

  • Constructor Details

    • MongoLockProvider

      public MongoLockProvider​(com.mongodb.client.MongoDatabase mongoDatabase)
      Uses Mongo to coordinate locks

    • MongoLockProvider

      public MongoLockProvider​(com.mongodb.client.MongoCollection<org.bson.Document> collection)
      Uses Mongo to coordinate locks
      Parameters:
      collection - Mongo collection to be used

  • Method Details