[dancer-users] Dancer and forking

[Andrew Beverley]

On 2015-07-08 00:58, Johandry Amador Segui wrote:
> Hi Andy,
> 
> I tried to use threads and it did not worked for me (maybe because of
> non safe thread modules I am using) so I use fork in a production
> application and it works good. I have some issues some times with
> MySQL that I have not fixed yet but they do not happen very often.
> 
> This is an example of how I use it:
> 
> sub execute {
> 
> 	# These 2 lines below were to eliminate the error that I mentioned
> before. It did not eliminated them just reduce them
> 	my $dbh = database();
> 	$dbh->{InactiveDestroy} = 1;
> 
> 	my $pid = fork();
> 
> 	if ($pid) {
> 		# This is the parent (Dancer) in case you want to do something here
> 		debug “Process started with PID $pid\n”;
> 
> 	} elsif ($pid == 0) {
> 		# This is the child, here is where I do all I need
> 		$template = ...
> 	} else {
> 		debug “Could not fork: $!\n”;
> 	}
> 
> 	# I have a variable to know if I’m running this sub from the web or 
> from CLI
> 	if ($cli) {
> 		my $output = waitpid($pid, 0);
> 		print “The process finish with output: $output”;
> 	}
> 
> 	return $template;
> }
> 
> This is just an example, not the entire code. If someone has a
> suggestion or improvement, it is welcome.

Surely you need an exit() in there somewhere for the child process, 
otherwise you'll end up with lots of web server threads?

Andy