[Buildbot] #2644: [nine] Add more MQ backends

[Buildbot trac]

#2644: [nine] Add more MQ backends
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Reporter:  dustin       |       Owner:
    Type:  enhancement  |      Status:  new
Priority:  major        |   Milestone:  0.9.0
 Version:               |  Resolution:
Keywords:  mq           |
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Comment (by tardyp):

 Good MQ usecase introduction is described here:

 http://www.rabbitmq.com/getstarted.html

 Technics from this document are relevent to buildbot:

 3) pub/sub: most of the bb usecases are using this
 (http://www.rabbitmq.com/tutorials/tutorial-three-python.html)
    - Inform other masters of new buildrequests
    - Inform status plugins of updates in the builds
    - Inform Web UI of changes in any of the data

 6) RPC: (http://www.rabbitmq.com/tutorials/tutorial-six-python.html)
 In order to avoid web masters to have db creds in write mode, long term
 plan is to use mq RPC technic for control APIS
    - force scheduler
    - build rebuild
    - build stop
    - buildrequest cancelation

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Ticket URL: <http://trac.buildbot.net/ticket/2644#comment:4>
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