Re: A method to asynchronously LISTEN ?

On Wed, 27 Feb 2019 at 05:47, Philippe Ebersohl <philippe(dot)ebersohl(at)dalim(dot)com>
wrote:

> Hello,
> I do not think there is a need for something like conn.listenSync().
> We were just intrigued about the test.
>
> In fact the current proposition should just work fine and we would like to
> test it.
> How could we have access to a postgresql-*.jdbc.jar that includes this
> feature ?
>
> Regards,
> Philippe
>

I just rebased it over the current code
https://github.com/pgjdbc/pgjdbc/pull/579
You should be able to build it manually using the commandline instructions
to get the pull

git checkout -b davecramer-notify master
git pull https://github.com/davecramer/pgjdbc.git notify

then use maven to build it

Dave Cramer

davec(at)postgresintl(dot)com
www.postgresintl.com

>
> ------------------------------
> *From: *"David G. Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com>
> *To: *"Dave Cramer" <pg(at)fastcrypt(dot)com>
> *Cc: *"Philippe Ebersohl" <philippe(dot)ebersohl(at)dalim(dot)com>, "List" <
> pgsql-jdbc(at)postgresql(dot)org>
> *Sent: *Tuesday, 26 February, 2019 22:17:12
> *Subject: *Re: A method to asynchronously LISTEN ?
>
> On Tue, Feb 26, 2019 at 12:04 PM Dave Cramer <pg(at)fastcrypt(dot)com> wrote:
>
>>
>>
>> On Tue, 26 Feb 2019 at 12:29, David G. Johnston <
>> david(dot)g(dot)johnston(at)gmail(dot)com> wrote:
>>
>>> The question being asked is whether executeUpdate method performs
>>> synchronous execution of the listener function queue during its execution.
>>>
>>> This after sending the command to the server and the server completing
>>> execution of the NOTIFY. This assumes that the server places the
>>> notification on the channel for pick-up immediately (which will not be the
>>> case within a transaction).
>>>
>>> While the client is, IIRC, synchronous, thus the local order of
>>> operations can be controlled, the server is asynchronous and thus this test
>>> is exposed to timing issues. Maybe we need something like
>>> conn.listenSync() that blocks until a notification payload is received on
>>> the connection...?
>>>
>>
>> kind of defeats the asynchronous aspect, no ?
>>
>>>
>>>>>
> You'd still want an asynchronous API for people but JavaScript introduced
> the "async/await" feature for a reason. In this case making it "sync"
> instead of coding up wait loop seems desirable. That said its quite
> possible I'm missing some existing feature as I haven't used this API at
> all.
>
> David J.
>
>
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>