On Oct 12, 2012, at 10:39 PM, Markus KARG wrote:
> Yes this is one form of COMET. And: No, typically the browser will not keep
> the connection open, since this only works if a really lot of constraints
> *all* are fulfilled:
I was unclear - I meant keep the *request* open. IOW, use one request for a long
time and send the response as a ..slow... stream of push messages. I thought
that is what all the pubsub guys do.
Thanks for the details - now going to enjoy them
Jan
> - The browser, the server, and all intermediate proxies must be http/1.1
> compliant AND implement the persistent connection feature (which is optional
> even in http/1.1), and all these systems must be bug-free.
> - The browser, the server, and all intermediate proxies must intend to
> actually use the persistent connection feature, as even a http/1.1 compliant
> party that fulfils the above constraints in some situations might
> intentionally prefer not to keep the connection open but instead close it
> temporarily and restart another connection later (e. g. if the traffic on
> the party is rather high, but the traffic on that push line is rather low),
> which is a valid implementation of http, unless http/1.0 will be officially
> "forbidden" (which typically will never happen).
> - All of the participating parties must do both above issues at the same
> time. If only one constraint is not fulfilled at any time, the connection
> cannot kept open.
>
> Example: You did your best efforts but for offloading reasons a Squid 3
> proxy is installed -- which does not implement http/1.1 completely and
> chances are high that it has lots of bugs... which foils the browser's and
> server's best efforts.
>
> You see, chances are very low that the connection actually is left open
> (unfortunately).
>
> Regards
> Markus
>
>> -----Original Message-----
>> From: Jan Algermissen [mailto:jan.algermissen_at_nordsc.com]
>> Sent: Freitag, 12. Oktober 2012 22:11
>> To: jsr339-experts_at_jax-rs-spec.java.net
>> Subject: [jsr339-experts] Re: How are suspended responses usually
>> managed?
>>
>>
>> On Oct 12, 2012, at 9:54 PM, Markus KARG wrote:
>>
>>> I'm rather sure you'll be very pleased by having a look at
>>> AsyncResponse's JavaDocs (the code example in the class docs showing
>>> how to implement COMET "pushing")... ;-)
>>
>> You mean the intro of
>>
>> http://jax-rs-spec.java.net/nonav/2.0-
>> SNAPSHOT/apidocs/javax/ws/rs/container/AsyncResponse.html
>>
>> Is that Comet? Would the browser open a new connection after receiving
>> the push?
>>
>>
>> Jan
>>
>>
>>>
>>>> -----Original Message-----
>>>> From: Jan Algermissen [mailto:jan.algermissen_at_nordsc.com]
>>>> Sent: Freitag, 12. Oktober 2012 21:37
>>>> To: jsr339-experts_at_jax-rs-spec.java.net
>>>> Subject: [jsr339-experts] Re: How are suspended responses usually
>>>> managed?
>>>>
>>>>
>>>> On Oct 12, 2012, at 9:28 PM, Markus KARG wrote:
>>>>
>>>>> Jan,
>>>>>
>>>>> just scanned the public draft of the spec and did not find the word
>>>>> "push" a single time! How did you come to the conclusion that the
>>>>> async API will allow you to implement frequent server pushes ontop
>>>>> of
>>>> it?
>>>>
>>>> I thought that was one of the motivations behind it and Bill
>> mentions
>>>> it as one in his Oct 9th talk on Infoq.
>>>>
>>>>
>>>>
>>>> Jan
>>>>
>>>>
>>>>>
>>>>> Regards
>>>>> Markus
>>>>>
>>>>>> -----Original Message-----
>>>>>> From: Jan Algermissen [mailto:jan.algermissen_at_nordsc.com]
>>>>>> Sent: Freitag, 12. Oktober 2012 16:11
>>>>>> To: jsr339-experts_at_jax-rs-spec.java.net
>>>>>> Subject: [jsr339-experts] Re: How are suspended responses usually
>>>>>> managed?
>>>>>>
>>>>>>
>>>>>> On Oct 12, 2012, at 3:49 PM, Bill Burke wrote:
>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 10/12/2012 9:38 AM, Jan Algermissen wrote:
>>>>>>>> Hi
>>>>>>>>
>>>>>>>> when a response is suspended by the async API the request
>> handing
>>>>>> thread is being 'released from duty' and can continue serving
>>>> requests.
>>>>>>>>
>>>>>>>> So far I understand. What I am not entirely clear about is what
>>>>>> happens with the suspended response - will these be 'parked' in an
>>>>>> extra thread? Or will there be one thread for each suspended
>>>> response?
>>>>>>>>
>>>>>>>
>>>>>>> Its up to you and your application. That's the idea.
>>>>>>
>>>>>> Ok, yes.
>>>>>>
>>>>>> Sorry for being stupid.. but:
>>>>>>
>>>>>> - so when I suspend a response without invoking a new thread
>>>>>> nothing happens except that a connection is being used (meaning
>>>>>> that a
>>>> queue
>>>>>> of 1000 responses would use up 1000
>>>>>> connections)
>>>>>>
>>>>>> - when I resume the response, the response will be sent in the
>>>>>> current thread of execution.
>>>>>>
>>>>>> That's simple, but I find the implications not so easy to see at
>>>> first.
>>>>>> Thanks.
>>>>>>
>>>>>>
>>>>>> What I would love to be able to do is to suspend/resume again.
>>>>>> Considering server push, it seems odd that I can have a long
>>>>>> running request without resource consumption *until* the first
>> bits
>>>>>> of the response are sent. What if I want to send one event every
>> Minute?
>>>> The
>>>>>> initial async doesn't really buy me that much, does it?
>>>>>>
>>>>>> (just trying to get my head straight)
>>>>>>
>>>>>> Jan
>>>>>>
>>>>>>
>>>>>>
>>>>>>>
>>>>>>> --
>>>>>>> Bill Burke
>>>>>>> JBoss, a division of Red Hat
>>>>>>> http://bill.burkecentral.com
>>>>>
>>>>>
>>>
>>>
>
>