Re: LISTEN / NOTIFY

On Mon, Oct 11, 2021 at 8:36 AM David G. Johnston <
david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

>
>
> On Monday, October 11, 2021, aditya desai <admad123(at)gmail(dot)com> wrote:
>
>> Hi,
>> Has anyone implemented LISTEN / NOTIFY to enqueue and dequeue messages to
>> and from Postgres? Do you have steps to implement it?
>>
>
> Listen/notify are not a queuing system, they are a notification system.
>

I agree with David - you _could_ implement a work queue using LISTEN /
NOTIFY as primitive components, but they are not anything like a complete
queuing system. I would recommend implementing any number of open source or
licensed message queue solutions that will work with Postgres. RabbitMQ is
widely known and used. I've used SideKiq and Resque (both being in Ruby, a
language I like). I think it would be unwise to implement your own queue
system directly on top of LISTEN/NOTIFY. There are so many edge cases to
queue management, it's almost like implementing your own encryption
algorithm on top of Postgres' math functions. There are OSS tools out there
that will almost certainly do what you want.

Steve