[Pulp-list] Messaging Questions

[Todd B Sanders]

On 07/12/2010 10:22 AM, Bryan Kearney wrote:
> On 07/12/2010 09:08 AM, Todd B Sanders wrote:
>> On 07/08/2010 05:06 PM, Jason Dobies wrote:
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>>>> Open questions which I see:
>>>>
>>>> 1) Does pulp require durable queues? Do I want to ensure that a packge
>>>> is updated the next time it wakes up? If so, we need to handle queue
>>>> purging. Perhaps this is tied to consumer deletion.
>>>>
>>>> 2) Can the same message (install package) be sent P2P Sync, Fire and
>>>> Forget, and broadcast. I think the answer to this should be yes. If 
>>>> so,
>>>> in broadcast, is there a notion of the success/failure?
>>> 1 and 2 are kinda related, so I'll answer both here.
>>>
>>> This is a really interesting question. If a user says to install a
>>> package and the agent isn't currently available, will the user still
>>> want it installed in the future when it is available?
>>>
>>> I think if we add a time factor to the request (i.e. "only do this if
>>> you get the message before 8am") I'm more inclined to go with only 
>>> using
>>> durable queues for package installs. It feels like too critical of an
>>> operation to leave open to a non-guaranteed paradigm.
>>>
>>>> 3) Will Jason Dobies choose to argue against himself who is arguing
>>>> against himself? if so, is he correct no matter what the outcome?
>>> I'm glad you came to the realization that I'm always correct. :)
>>>
>>>> 4) Is there a hearbeat requirement? I have not heard of any.
>>> It's starting to sound like there is. If we go durable queues, this is
>>> gonna be the way we clean up queues for dead agents. Even if there
>>> isn't, I think it's a trivial enough addition to give us minimalistic
>>> availability information. Good bang for the buck there.
>>
>> We sort of had this with Satellite and rhn-check. Out of the box,
>> managed systems check in with the server every 4-hours. We then
>> high-light inactive systems. Seems to me that a heartbeat is a good way
>> to achieve similar information. So, IMO, it is a requirement.
>>
>> -Todd
>
> Do you envision the heartbeat over rest, or AMQP?

Was chatting with jortel about this.  Thinking AMQP will be more 
efficient.  No tcp/http overhead.

-Todd
>
> -- bk