package Mojolicious::Plugin::Webtail;
use Mojo::Base 'Mojolicious::Plugin';
our $VERSION = '0.02';
use Mojo::Util qw{ slurp };
use Carp ();
use Encode ();
has 'template' => <<'TEMPLATE';
<html><head>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title><%= $file %> - Webtail</title>
%= stylesheet begin
/* Stolen from https://github.com/r7kamura/webtail */
* {
margin: 0;
padding: 0;
}
body {
margin: 1em 0;
color: #ddd;
background: #111;
}
pre {
padding: 0 1em;
line-height: 1.25;
font-family: "Monaco", "Consolas", monospace;
}
#message {
position:fixed;
top:1em;
right:1em;
}
% end
%= javascript 'https://ajax.googleapis.com/ajax/libs/jquery/1.7/jquery.min.js'
%= javascript begin
$(function() {
var autoscroll = true;
// press 's' key to toggle autoscroll
$(window).keydown(function(e) { if (e.keyCode == 83 ) autoscroll = (autoscroll) ? false : true });
var ws = new (WebSocket || MozWebSocket)('<%= $ws_url %>');
var timer_id;
ws.onopen = function() {
console.log('Connection opened');
timer_id = setInterval(
function() {
console.log('Connection keepalive');
ws.send('keepalive');
},
1000 * 240
);
};
ws.onmessage = function(msg) {
if (msg.data == '\n' && $('pre:last').text() == '\n') return;
$('<pre>').text(msg.data).appendTo('body');
if (autoscroll) $('html, body').scrollTop($(document).height());
% if ($webtailrc) {
// webtailrc
<%== $webtailrc %>
% }
};
ws.onclose = function() {
console.warn('Connection closed');
clearInterval(timer_id);
};
ws.onerror = function(msg) {
console.error(msg.data);
};
});
% end
</head><body>
<div id="message">press 's' to toggle autoscroll</div>
</body></html>
TEMPLATE
has 'file';
has 'webtailrc';
has '_tail';
has '_clients' => sub { +{} };
sub DESTROY {
my $self = shift;
$self->_tail->close if $self->_tail;
}
sub _prepare_stream {
my ( $self, $app ) = @_;
return if ( $self->_tail );
my ( $fh, $pid );
if ( $self->file ) {
$pid = open( $fh, '-|', 'tail', '-F', '-n', '0', $self->file ) or Carp::croak "fork failed: $!";
} else {
$fh = *STDIN;
}
$app->log->debug( sprintf("tailing file: %s", $self->file || 'STDIN') );
my $stream = Mojo::IOLoop::Stream->new($fh)->timeout(0);
my $stream_id = Mojo::IOLoop->stream($stream);
$stream->on( read => sub {
my ($stream, $chunk) = @_;
for my $key (keys %{ $self->_clients }) {
my $tx = $self->_clients->{$key};
next unless $tx->is_websocket;
$tx->send( Encode::decode_utf8($chunk) );
$app->log->debug( sprintf('sent %s', $key ) );
}
} );
$stream->on( error => sub {
$app->log->error( sprintf('error %s', $_[1] ) );
Mojo::IOLoop->remove($stream_id);
$self->_tail(undef);
});
$stream->on( close => sub {
$app->log->debug('close tail stream');
if ($pid) {
kill 'TERM', $pid if ( kill 0, $pid );
waitpid( $pid, 0 );
};
Mojo::IOLoop->remove($stream_id);
$self->_tail(undef);
});
$self->_tail($stream);
$app->log->debug( sprintf('connected tail stream %s', $stream_id ) );
}
sub register {
my $plugin = shift;
my ( $app, $args ) = @_;
$plugin->file( $args->{file} || '' );
$plugin->webtailrc( $args->{webtailrc} || '' );
$app->hook(
before_dispatch => sub {
my $c = shift;
my $path = $c->req->url->path;
return unless ($c->req->url->path =~ m|^/webtail/?$|);
if ( $c->tx->is_websocket ) {
$plugin->_prepare_stream($app);
my $tx = $c->tx;
$plugin->_clients->{"$tx"} = $tx;
$c->app->log->debug( sprintf('connected %s', "$tx" ) );
Mojo::IOLoop->stream( $tx->connection )->timeout(300)->on( timeout => sub {
$c->finish;
delete $plugin->_clients->{"$tx"};
$c->app->log->debug( sprintf('timeout %s', $tx ) );
});
$c->on( message => sub {
$c->app->log->debug( sprintf('message "%s" from %s', $_[1], $tx ) );
} );
$c->on( finish => sub {
delete $plugin->_clients->{"$tx"};
$c->app->log->debug( sprintf('finish %s', $tx ) );
} );
$c->res->headers->content_type('text/event-stream');
return;
}
my $ws_url = $c->req->url->to_abs->scheme('ws')->to_string;
$c->render(
inline => $plugin->template,
ws_url => $ws_url,
webtailrc => ( $plugin->webtailrc ) ? slurp( $plugin->webtailrc ) : '',
file => $args->{file} || 'STDIN',
);
},
);
return $app;
}
1;
__END__
=head1 NAME
Mojolicious::Plugin::Webtail - display tail to your browser
=head1 SYNOPSIS
use Mojolicious::Lite;
plugin( 'Webtail', file => "/path/to/logfile", webtailrc => '/path/to/webtail.rc' );
app->start;
or
> perl -Mojo -e 'a->plugin("Webtail", file => "/path/to/logfile", webtailrc => "/path/to/webtail.rc")->start' daemon
or
> tail -f /path/to/logfile | perl -Mojo -e 'a->plugin("Webtail", webtailrc => "/path/to/webtail.rc")->start' daemon
and access "http://host:port/webtail" in your web browser.
=head1 DESCRIPTION
Mojolicious::Plugin::Webtail is display tail to your browser by WebSocket.
=head1 METHODS
L<Mojolicious::Plugin::Webtail> inherits all methods from :<Mojolicious::Plugin>.
=head1 OPTIONS
L<Mojolicious::Plugin::Webtail> supports the following options.
=head2 C<file>
displays the contents of C<file> or, by default, its C<STDIN>.
=head2 C<webtailrc>
define your custom callback in C<webtail> file.
the code in C<webtail> file is executed when a new line is inserted.
=head1 AUTHOR
hayajo E<lt>hayajo@cpan.orgE<gt>
=head1 SEE ALSO
L<https://github.com/r7kamura/webtail>
=head1 LICENSE
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself.
=cut