Apache RocketMQ 
Apache RocketMQ is a low latency, reliable, scalable, easy to use message oriented middleware born from alibaba massive messaging business.
It offers a variety of features as follows:
- Pub/Sub and P2P messaging model
- Reliable FIFO and strict sequential messaging in the same queue
- Long pull queue model,also support push consumption style
- Million message accumulation ability in single queue
- Over a variety of messaging protocols.such as JMS,MQTT etc.
- Distributed high available deploy architecture, meets at least once message delivery semantics
- Docker images for isolated testing and cloud Isolated clusters
- Feature-rich administrative dashboard for configuration,metrics and monitoring
Learn it & Contact us
- Mailing Lists: http://rocketmq.incubator.apache.org/about/contact/
- Home: https://rocketmq.incubator.apache.org
- Wiki: https://cwiki.apache.org/confluence/display/ROCKETMQ/Apache+RocketMQ+Home
- Issues: https://issues.apache.org/jira/browse/RocketMQ
- Ask: http://stackoverflow.com/questions/tagged/rocketmq or https://www.quora.com/topic/RocketMQ
Apache RocketMQ Community
Contributing
We are always very happy to have contributions, whether for trivial cleanups,big new features or other material rewards. more details see here
License
Apache License, Version 2.0 Copyright (C) Apache Software Foundation