Re: POE modules advice

It sounds like you're putting the cart before the horse. POE::Wheel::Run includes parent/child process communication. POE::Component::Client::HTTP is not a a HTTP server. If your "clients" are simple programs, they could be implemented with plain LWP to talk to a POE-based HTTP server. You haven't explicitly said the httpd is running POE; I'm assuming yes because of the POE::Wheel::Run.

What I think (which is based on incomplete information and is probably wrong):

Plain old clients. LPW, curl, wget, whatever. This handles the client/httpd communication.
HTTP server, using one of the POE httpd components (your choice).
POE::Wheel::Run to run child processes and deal with httpd/child communication.
Worker pool management is a vague concept and probably includes some custom logic. Until I know more, you probably write this part.

I would have the child processes report their status as it changes, and then store that status in the HTTP session (not a POE session). When the client polls for status, it can be satisfied by the session information rather than asking the child process (which may have exited or crashed anyway).

http://poe.perl.org/?POE_Cookbook/Job_Server is a telnet based job server. It's not appropriate for your task, but it does show one way to write a server that accepts jobs and then runs them in separate processes.

Sorry for the vague answer. I may be able to narrow down my advice if you provide more specifics.

-- Rocco Caputo - http://poe.perl.org/

Comment on Re: POE modules advice

Replies are listed 'Best First'.
Re^2: POE modules advice by Neid (Scribe) on Mar 19, 2009 at 21:45 UTC
Yes that's true, httpd will be also POE (e.g. POE::Component::Server::HTTP ) I saw that POE::Wheel::Run uses stdin/stdout for communication. My workers is a perl code so I would pass subroutine reference to Wheel::Run 'Program' argument. Unfortunately that code may print some debug stuff. I was thinking about worker code as something similar to: `sub worker{ my $self = shift; while( my $task = $some_queue->dequeue ) { # do_something() can print debug output to STDOUT my $result = $self->do_something(); my $status = { result => $result, time => time(), worker_id => + $self->id}; $self->update_status( $status); } }` [download] And parent code something like: `sub parent { my $self = shift; $some_queue->enqueue( $new_task); } sub update_status_event{ my $status = shift; # do something with status #... }` [download] So I think POE::Wheel::Run for inter-process communication is not enough. Any advice here? Thanks,	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re^2: POE modules advice
by Neid (Scribe) on Mar 19, 2009 at 21:45 UTC

sub worker{
    my $self = shift;

    while( my $task = $some_queue->dequeue ) {
        
        # do_something() can print debug output to STDOUT
        my $result = $self->do_something();
        
        my $status = { result => $result, time => time(), worker_id =>
+ $self->id};
        $self->update_status( $status);
    }

}
[download]

sub parent {
    my $self = shift;

    $some_queue->enqueue( $new_task);
}

sub update_status_event{
    my $status = shift;

    # do something with status
    #...
}
[download]

[reply]
[d/l]
[select]