Catalyst::Engine - The Catalyst Engine

Catalyst-Runtime documentation Contained in the Catalyst-Runtime distribution.

Index

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NAME

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Catalyst::Engine - The Catalyst Engine

SYNOPSIS

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See Catalyst.

DESCRIPTION

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METHODS

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$self->finalize_body($c)

Finalize body. Prints the response output.

$self->finalize_cookies($c)

Create CGI::Simple::Cookie objects from $c->res->cookies, and set them as response headers.

$self->finalize_error($c)

Output an appropriate error message. Called if there's an error in $c after the dispatch has finished. Will output debug messages if Catalyst is in debug mode, or a `please come back later` message otherwise.

$self->finalize_headers($c)

Abstract method, allows engines to write headers to response

$self->finalize_read($c)

$self->finalize_uploads($c)

Clean up after uploads, deleting temp files.

$self->prepare_body($c)

sets up the Catalyst::Request object body using HTTP::Body

$self->prepare_body_chunk($c)

Add a chunk to the request body.

$self->prepare_body_parameters($c)

Sets up parameters from body.

$self->prepare_connection($c)

Abstract method implemented in engines.

$self->prepare_cookies($c)

Parse cookies from header. Sets a CGI::Simple::Cookie object.

$self->prepare_headers($c)

$self->prepare_parameters($c)

sets up parameters from query and post parameters.

$self->prepare_path($c)

abstract method, implemented by engines.

$self->prepare_request($c)

$self->prepare_query_parameters($c)

process the query string and extract query parameters.

$self->prepare_read($c)

prepare to read from the engine.

$self->prepare_request(@arguments)

Populate the context object from the request object.

$self->prepare_uploads($c)

$self->prepare_write($c)

Abstract method. Implemented by the engines.

$self->read($c, [$maxlength])

Reads from the input stream by calling $self->read_chunk.

Maintains the read_length and read_position counters as data is read.

$self->read_chunk($c, $buffer, $length)

Each engine implements read_chunk as its preferred way of reading a chunk of data. Returns the number of bytes read. A return of 0 indicates that there is no more data to be read.

$self->read_length

The length of input data to be read. This is obtained from the Content-Length header.

$self->read_position

The amount of input data that has already been read.

$self->run($c)

Start the engine. Implemented by the various engine classes.

$self->write($c, $buffer)

Writes the buffer to the client.

$self->unescape_uri($uri)

Unescapes a given URI using the most efficient method available. Engines such as Apache may implement this using Apache's C-based modules, for example.

$self->finalize_output

<obsolete>, see finalize_body

$self->env

Hash containing enviroment variables including many special variables inserted by WWW server - like SERVER_*, REMOTE_*, HTTP_* ...

Before accesing enviroment variables consider whether the same information is not directly available via Catalyst objects $c->request, $c->engine ...

BEWARE: If you really need to access some enviroment variable from your Catalyst application you should use $c->engine->env->{VARNAME} instead of $ENV{VARNAME}, as in some enviroments the %ENV hash does not contain what you would expect.

AUTHORS

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Catalyst Contributors, see Catalyst.pm

COPYRIGHT

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This library is free software. You can redistribute it and/or modify it under the same terms as Perl itself.

Catalyst-Runtime documentation Contained in the Catalyst-Runtime distribution. 
package Catalyst::Engine;

use Moose;
with 'MooseX::Emulate::Class::Accessor::Fast';

use CGI::Simple::Cookie;
use Data::Dump qw/dump/;
use Errno 'EWOULDBLOCK';
use HTML::Entities;
use HTTP::Body;
use HTTP::Headers;
use URI::QueryParam;

use namespace::clean -except => 'meta';

has env => (is => 'rw');

# input position and length
has read_length => (is => 'rw');
has read_position => (is => 'rw');

has _prepared_write => (is => 'rw');

# Amount of data to read from input on each pass
our $CHUNKSIZE = 64 * 1024;


sub finalize_body {
    my ( $self, $c ) = @_;
    my $body = $c->response->body;
    no warnings 'uninitialized';
    if ( blessed($body) && $body->can('read') or ref($body) eq 'GLOB' ) {
        my $got;
        do {
            $got = read $body, my ($buffer), $CHUNKSIZE;
            $got = 0 unless $self->write( $c, $buffer );
        } while $got > 0;

        close $body;
    }
    else {
        $self->write( $c, $body );
    }
}


sub finalize_cookies {
    my ( $self, $c ) = @_;

    my @cookies;
    my $response = $c->response;

    foreach my $name (keys %{ $response->cookies }) {

        my $val = $response->cookies->{$name};

        my $cookie = (
            blessed($val)
            ? $val
            : CGI::Simple::Cookie->new(
                -name    => $name,
                -value   => $val->{value},
                -expires => $val->{expires},
                -domain  => $val->{domain},
                -path    => $val->{path},
                -secure  => $val->{secure} || 0,
                -httponly => $val->{httponly} || 0,
            )
        );

        push @cookies, $cookie->as_string;
    }

    for my $cookie (@cookies) {
        $response->headers->push_header( 'Set-Cookie' => $cookie );
    }
}


sub _dump_error_page_element {
    my ($self, $i, $element) = @_;
    my ($name, $val)  = @{ $element };

    # This is fugly, but the metaclass is _HUGE_ and demands waaay too much
    # scrolling. Suggestions for more pleasant ways to do this welcome.
    local $val->{'__MOP__'} = "Stringified: "
        . $val->{'__MOP__'} if ref $val eq 'HASH' && exists $val->{'__MOP__'};

    my $text = encode_entities( dump( $val ));
    sprintf <<"EOF", $name, $text;
<h2><a href="#" onclick="toggleDump('dump_$i'); return false">%s</a></h2>
<div id="dump_$i">
    <pre wrap="">%s</pre>
</div>
EOF
}

sub finalize_error {
    my ( $self, $c ) = @_;

    $c->res->content_type('text/html; charset=utf-8');
    my $name = ref($c)->config->{name} || join(' ', split('::', ref $c));

    my ( $title, $error, $infos );
    if ( $c->debug ) {

        # For pretty dumps
        $error = join '', map {
                '<p><code class="error">'
              . encode_entities($_)
              . '</code></p>'
        } @{ $c->error };
        $error ||= 'No output';
        $error = qq{<pre wrap="">$error</pre>};
        $title = $name = "$name on Catalyst $Catalyst::VERSION";
        $name  = "<h1>$name</h1>";

        # Don't show context in the dump
        $c->req->_clear_context;
        $c->res->_clear_context;

        # Don't show body parser in the dump
        $c->req->_clear_body;

        my @infos;
        my $i = 0;
        for my $dump ( $c->dump_these ) {
            push @infos, $self->_dump_error_page_element($i, $dump);
            $i++;
        }
        $infos = join "\n", @infos;
    }
    else {
        $title = $name;
        $error = '';
        $infos = <<"";
<pre>
(en) Please come back later
(fr) SVP veuillez revenir plus tard
(de) Bitte versuchen sie es spaeter nocheinmal
(at) Konnten's bitt'schoen spaeter nochmal reinschauen
(no) Vennligst prov igjen senere
(dk) Venligst prov igen senere
(pl) Prosze sprobowac pozniej
(pt) Por favor volte mais tarde
(ru) Попробуйте еще раз позже
(ua) Спробуйте ще раз пізніше
</pre>

        $name = '';
    }
    $c->res->body( <<"" );
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
    <meta http-equiv="Content-Language" content="en" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>$title</title>
    <script type="text/javascript">
        <!--
        function toggleDump (dumpElement) {
            var e = document.getElementById( dumpElement );
            if (e.style.display == "none") {
                e.style.display = "";
            }
            else {
                e.style.display = "none";
            }
        }
        -->
    </script>
    <style type="text/css">
        body {
            font-family: "Bitstream Vera Sans", "Trebuchet MS", Verdana,
                         Tahoma, Arial, helvetica, sans-serif;
            color: #333;
            background-color: #eee;
            margin: 0px;
            padding: 0px;
        }
        :link, :link:hover, :visited, :visited:hover {
            color: #000;
        }
        div.box {
            position: relative;
            background-color: #ccc;
            border: 1px solid #aaa;
            padding: 4px;
            margin: 10px;
        }
        div.error {
            background-color: #cce;
            border: 1px solid #755;
            padding: 8px;
            margin: 4px;
            margin-bottom: 10px;
        }
        div.infos {
            background-color: #eee;
            border: 1px solid #575;
            padding: 8px;
            margin: 4px;
            margin-bottom: 10px;
        }
        div.name {
            background-color: #cce;
            border: 1px solid #557;
            padding: 8px;
            margin: 4px;
        }
        code.error {
            display: block;
            margin: 1em 0;
            overflow: auto;
        }
        div.name h1, div.error p {
            margin: 0;
        }
        h2 {
            margin-top: 0;
            margin-bottom: 10px;
            font-size: medium;
            font-weight: bold;
            text-decoration: underline;
        }
        h1 {
            font-size: medium;
            font-weight: normal;
        }
        /* from http://users.tkk.fi/~tkarvine/linux/doc/pre-wrap/pre-wrap-css3-mozilla-opera-ie.html */
        /* Browser specific (not valid) styles to make preformatted text wrap */
        pre {
            white-space: pre-wrap;       /* css-3 */
            white-space: -moz-pre-wrap;  /* Mozilla, since 1999 */
            white-space: -pre-wrap;      /* Opera 4-6 */
            white-space: -o-pre-wrap;    /* Opera 7 */
            word-wrap: break-word;       /* Internet Explorer 5.5+ */
        }
    </style>
</head>
<body>
    <div class="box">
        <div class="error">$error</div>
        <div class="infos">$infos</div>
        <div class="name">$name</div>
    </div>
</body>
</html>


    # Trick IE. Old versions of IE would display their own error page instead
    # of ours if we'd give it less than 512 bytes.
    $c->res->{body} .= ( ' ' x 512 );

    # Return 500
    $c->res->status(500);
}


sub finalize_headers { }


sub finalize_read { }


sub finalize_uploads {
    my ( $self, $c ) = @_;

    my $request = $c->request;
    foreach my $key (keys %{ $request->uploads }) {
        my $upload = $request->uploads->{$key};
        unlink grep { -e $_ } map { $_->tempname }
          (ref $upload eq 'ARRAY' ? @{$upload} : ($upload));
    }

}


sub prepare_body {
    my ( $self, $c ) = @_;

    my $appclass = ref($c) || $c;
    if ( my $length = $self->read_length ) {
        my $request = $c->request;
        unless ( $request->_body ) {
            my $type = $request->header('Content-Type');
            $request->_body(HTTP::Body->new( $type, $length ));
            $request->_body->tmpdir( $appclass->config->{uploadtmp} )
              if exists $appclass->config->{uploadtmp};
        }

        # Check for definedness as you could read '0'
        while ( defined ( my $buffer = $self->read($c) ) ) {
            $c->prepare_body_chunk($buffer);
        }

        # paranoia against wrong Content-Length header
        my $remaining = $length - $self->read_position;
        if ( $remaining > 0 ) {
            $self->finalize_read($c);
            Catalyst::Exception->throw(
                "Wrong Content-Length value: $length" );
        }
    }
    else {
        # Defined but will cause all body code to be skipped
        $c->request->_body(0);
    }
}


sub prepare_body_chunk {
    my ( $self, $c, $chunk ) = @_;

    $c->request->_body->add($chunk);
}


sub prepare_body_parameters {
    my ( $self, $c ) = @_;

    return unless $c->request->_body;

    $c->request->body_parameters( $c->request->_body->param );
}


sub prepare_connection { }


sub prepare_cookies {
    my ( $self, $c ) = @_;

    if ( my $header = $c->request->header('Cookie') ) {
        $c->req->cookies( { CGI::Simple::Cookie->parse($header) } );
    }
}


sub prepare_headers { }


sub prepare_parameters {
    my ( $self, $c ) = @_;

    my $request = $c->request;
    my $parameters = $request->parameters;
    my $body_parameters = $request->body_parameters;
    my $query_parameters = $request->query_parameters;
    # We copy, no references
    foreach my $name (keys %$query_parameters) {
        my $param = $query_parameters->{$name};
        $parameters->{$name} = ref $param eq 'ARRAY' ? [ @$param ] : $param;
    }

    # Merge query and body parameters
    foreach my $name (keys %$body_parameters) {
        my $param = $body_parameters->{$name};
        my @values = ref $param eq 'ARRAY' ? @$param : ($param);
        if ( my $existing = $parameters->{$name} ) {
          unshift(@values, (ref $existing eq 'ARRAY' ? @$existing : $existing));
        }
        $parameters->{$name} = @values > 1 ? \@values : $values[0];
    }
}


sub prepare_path { }


sub prepare_query_parameters {
    my ( $self, $c, $query_string ) = @_;

    # Check for keywords (no = signs)
    # (yes, index() is faster than a regex :))
    if ( index( $query_string, '=' ) < 0 ) {
        $c->request->query_keywords( $self->unescape_uri($query_string) );
        return;
    }

    my %query;

    # replace semi-colons
    $query_string =~ s/;/&/g;

    my @params = grep { length $_ } split /&/, $query_string;

    for my $item ( @params ) {

        my ($param, $value)
            = map { $self->unescape_uri($_) }
              split( /=/, $item, 2 );

        $param = $self->unescape_uri($item) unless defined $param;

        if ( exists $query{$param} ) {
            if ( ref $query{$param} ) {
                push @{ $query{$param} }, $value;
            }
            else {
                $query{$param} = [ $query{$param}, $value ];
            }
        }
        else {
            $query{$param} = $value;
        }
    }

    $c->request->query_parameters( \%query );
}


sub prepare_read {
    my ( $self, $c ) = @_;

    # Initialize the read position
    $self->read_position(0);

    # Initialize the amount of data we think we need to read
    $self->read_length( $c->request->header('Content-Length') || 0 );
}


sub prepare_request { }


sub prepare_uploads {
    my ( $self, $c ) = @_;

    my $request = $c->request;
    return unless $request->_body;

    my $uploads = $request->_body->upload;
    my $parameters = $request->parameters;
    foreach my $name (keys %$uploads) {
        my $files = $uploads->{$name};
        my @uploads;
        for my $upload (ref $files eq 'ARRAY' ? @$files : ($files)) {
            my $headers = HTTP::Headers->new( %{ $upload->{headers} } );
            my $u = Catalyst::Request::Upload->new
              (
               size => $upload->{size},
               type => $headers->content_type,
               headers => $headers,
               tempname => $upload->{tempname},
               filename => $upload->{filename},
              );
            push @uploads, $u;
        }
        $request->uploads->{$name} = @uploads > 1 ? \@uploads : $uploads[0];

        # support access to the filename as a normal param
        my @filenames = map { $_->{filename} } @uploads;
        # append, if there's already params with this name
        if (exists $parameters->{$name}) {
            if (ref $parameters->{$name} eq 'ARRAY') {
                push @{ $parameters->{$name} }, @filenames;
            }
            else {
                $parameters->{$name} = [ $parameters->{$name}, @filenames ];
            }
        }
        else {
            $parameters->{$name} = @filenames > 1 ? \@filenames : $filenames[0];
        }
    }
}


sub prepare_write { }


sub read {
    my ( $self, $c, $maxlength ) = @_;

    my $remaining = $self->read_length - $self->read_position;
    $maxlength ||= $CHUNKSIZE;

    # Are we done reading?
    if ( $remaining <= 0 ) {
        $self->finalize_read($c);
        return;
    }

    my $readlen = ( $remaining > $maxlength ) ? $maxlength : $remaining;
    my $rc = $self->read_chunk( $c, my $buffer, $readlen );
    if ( defined $rc ) {
        if (0 == $rc) { # Nothing more to read even though Content-Length
                        # said there should be. FIXME - Warn in the log here?
            $self->finalize_read;
            return;
        }
        $self->read_position( $self->read_position + $rc );
        return $buffer;
    }
    else {
        Catalyst::Exception->throw(
            message => "Unknown error reading input: $!" );
    }
}


sub read_chunk { }


sub run { }


sub write {
    my ( $self, $c, $buffer ) = @_;

    unless ( $self->_prepared_write ) {
        $self->prepare_write($c);
        $self->_prepared_write(1);
    }

    return 0 if !defined $buffer;

    my $len   = length($buffer);
    my $wrote = syswrite STDOUT, $buffer;

    if ( !defined $wrote && $! == EWOULDBLOCK ) {
        # Unable to write on the first try, will retry in the loop below
        $wrote = 0;
    }

    if ( defined $wrote && $wrote < $len ) {
        # We didn't write the whole buffer
        while (1) {
            my $ret = syswrite STDOUT, $buffer, $CHUNKSIZE, $wrote;
            if ( defined $ret ) {
                $wrote += $ret;
            }
            else {
                next if $! == EWOULDBLOCK;
                return;
            }

            last if $wrote >= $len;
        }
    }

    return $wrote;
}


sub unescape_uri {
    my ( $self, $str ) = @_;

    $str =~ s/(?:%([0-9A-Fa-f]{2})|\+)/defined $1 ? chr(hex($1)) : ' '/eg;

    return $str;
}


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