taskq
Distributed task queue backed by MongoDB.
Usage
npm install taskq
Limitations
- Requires MongoDb 3.2+ for partial index support.
- For sharded collections, the sharding key must be
_id. - System time should be synchronized across the cluster.
FAQ
Why MongoDB?
This project focuses on leveraging MongoDB's scalability and flexibility (e.g. MapReduce on the queue). For other needs, see also kafka or RabbitMQ or Celery.
Why Taskq?
Most MongoDB based solutions are using
findAndModifydirectly, so they simply won't work on sharded collections, becausefindAndModifythrough mongos must contain the sharding key, which is often the unknown task id. In addtion, Taskq provides both priority queue and task scheduler, in a single collection.
How to improve read performance on sharded collections?
If your data is evenly distributed and you have more clients than mongod shards, you may try to stop the balancer and connect to the unsharded mongod directly. But keep in mind that bypassing mongos is DANGEROUS, your data might get lost in the twisted nether ...
License
(The MIT License)
Copyright (c) 2016-2017 Yichao 'Peak' Ji
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.