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Re: Parallel download Tk ( threads Thread::Queue LWP::UserAgent WWW::Mechanize)

by Anonymous Monk
on Jan 01, 2019 at 09:09 UTC ( #1227857=note: print w/replies, xml ) Need Help??


in reply to Parallel download Tk

Hi

Example

#!/usr/bin/perl -- ## perltidy -olq -csc -csci=10 -cscl="sub : BEGIN END" -otr -opr -ce +-nibc -i=4 -pt=0 "-nsak=*" use strict; use warnings; use threads stack_size => 4096; use Thread::Queue; Main( @ARGV ); exit( 0 ); sub Main { my $qin = Thread::Queue->new(); ## jobs to do in background my $qout = Thread::Queue->new(); ## results for gui in foreground my $guithread = threads->create( \&tkgui, $qin, $qout ); ## don't wait for background downloading service workers / mechtitles threads->create( \&mechtitles, $qin, $qout ) for 1 .. 2; $guithread->join; ## wait for gui to finish return; } ## end sub Main sub mechtitles { my( $qin, $qout ) = @_; threads->detach(); ## can't join this thread it returns nothing + :) require WWW::Mechanize; require Time::HiRes; my $ua = WWW::Mechanize->new( autocheck => 0 ); while( 1 ) { #~ if( defined( my $url = $qin->popnow ) ) { if( defined( my $url = $qin->pop ) ) { $ua->get( $url ); my $title = eval { $ua->title }; $title ||= $ua->res->status_line; my $worker = sprintf 'worker(%s)', threads->tid; $qout->push( "$worker $url =>\n $title\n" ); } Time::HiRes::usleep( 33 * 1000 ); ## sleep microseconds ## be "nice" give other thread a time slice } } ## end sub mechtitles sub tkgui { my( $qin, $qout ) = @_; require Tk; #~ require Tk::ROText; my $mw = Tk::tkinit(); my $pending = ""; my $l = $mw->Label( -textvariable => \$pending )->pack; #~ my $t = $mw->ROText()->pack; my $t = $mw->Text()->pack; my $b = $mw->Button( -text => 'enqueue another 3 example.com', )-> +pack; $b->configure( -command => [ \&q_pusher, $b, $qin, ], ); $b->focus; $mw->repeat( 500, ## millisecond [ \&pop_to_pending, $t, \$pending, $qin, $qout, ], ); $mw->MainLoop; return; } ## end sub tkgui sub q_pusher { my( $b, $qin ) = @_; $qin->push( 'http://example.com' ) for 1 .. 4; #~ $b->configure( -state => "disabled" ); return; } sub pop_to_pending { my( $t, $pending, $qin, $qout ) = @_; if( defined( my $item = $qout->popnow ) ) { $t->insert( q!end!, join( '', $item ) ); } $$pending = 'Jobs awaiting workers ' . $qin->pending; $t->update; return; } sub Thread::Queue::append { goto &Thread::Queue::enqueue } sub Thread::Queue::remove { goto &Thread::Queue::dequeue } sub Thread::Queue::push { goto &Thread::Queue::enqueue } sub Thread::Queue::shift { goto &Thread::Queue::dequeue } sub Thread::Queue::popnow { goto &Thread::Queue::dequeue_nb } sub Thread::Queue::pop { goto &Thread::Queue::dequeue } __END__

Tips
Re: Perl Tk nonblocking (threads queue)
Re: Basic examples of perl/tk and fork

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