File Coverage

lib/Template/Document.pm

Criterion	Covered	Total	%
statement	79	90	87.7
branch	17	28	60.7
condition	10	17	58.8
subroutine	13	15	86.6
pod	8	8	100.0
total	127	158	80.3

##============================================================= -*-Perl-*-
#
# Template::Document
#
# DESCRIPTION
#   Module defining a class of objects which encapsulate compiled
#   templates, storing additional block definitions and metadata
#   as well as the compiled Perl sub-routine representing the main
#   template content.
#
# AUTHOR
#   Andy Wardley
#
# COPYRIGHT
#   Copyright (C) 1996-2007 Andy Wardley.  All Rights Reserved.
#
#   This module is free software; you can redistribute it and/or
#   modify it under the same terms as Perl itself.
#
#============================================================================

package Template::Document;

use strict;
use warnings;
use base 'Template::Base';
use Template::Constants;

our $VERSION = 2.79;
our $DEBUG   = 0 unless defined $DEBUG;
our $ERROR   = '';
our ($COMPERR, $AUTOLOAD, $UNICODE);

BEGIN {
    # UNICODE is supported in versions of Perl from 5.008 onwards
    if ($UNICODE = $] > 5.007 ? 1 : 0) {
        if ($] > 5.008) {
            # utf8::is_utf8() available from Perl 5.8.1 onwards
            *is_utf8 = \&utf8::is_utf8;
        }
        elsif ($] == 5.008) {
            # use Encode::is_utf8() for Perl 5.8.0
            require Encode;
            *is_utf8 = \&Encode::is_utf8;
        }
    }
}


#========================================================================
#                     -----  PUBLIC METHODS -----
#========================================================================

#------------------------------------------------------------------------
# new(\%document)
#
# Creates a new self-contained Template::Document object which
# encapsulates a compiled Perl sub-routine, $block, any additional
# BLOCKs defined within the document ($defblocks, also Perl sub-routines)
# and additional $metadata about the document.
#------------------------------------------------------------------------

sub new {
    my ($class, $doc) = @_;
    my ($block, $defblocks, $variables, $metadata) = @$doc{ qw( BLOCK DEFBLOCKS VARIABLES METADATA ) };
    $defblocks ||= { };
    $metadata  ||= { };

    # evaluate Perl code in $block to create sub-routine reference if necessary
    unless (ref $block) {
        local $SIG{__WARN__} = \&catch_warnings;
        $COMPERR = '';

        # DON'T LOOK NOW! - blindly untainting can make you go blind!
        $block =~ /(.*)/s;
        $block = $1;

        $block = eval $block;
        return $class->error($@)
            unless defined $block;
    }

    # same for any additional BLOCK definitions
    @$defblocks{ keys %$defblocks } =
        # MORE BLIND UNTAINTING - turn away if you're squeamish
        map {
            ref($_)
                ? $_
                : ( /(.*)/s && eval($1) or return $class->error($@) )
            } values %$defblocks;

    bless {
        %$metadata,
        _BLOCK     => $block,
        _DEFBLOCKS => $defblocks,
        _VARIABLES => $variables,
        _HOT       => 0,
    }, $class;
}


#------------------------------------------------------------------------
# block()
#
# Returns a reference to the internal sub-routine reference, _BLOCK,
# that constitutes the main document template.
#------------------------------------------------------------------------

sub block {
    return $_[0]->{ _BLOCK };
}


#------------------------------------------------------------------------
# blocks()
#
# Returns a reference to a hash array containing any BLOCK definitions
# from the template.  The hash keys are the BLOCK name and the values
# are references to Template::Document objects.  Returns 0 (# an empty hash)
# if no blocks are defined.
#------------------------------------------------------------------------

sub blocks {
    return $_[0]->{ _DEFBLOCKS };
}


#-----------------------------------------------------------------------
# variables()
#
# Returns a reference to a hash of variables used in the template.
# This requires the TRACE_VARS option to be enabled.
#-----------------------------------------------------------------------

sub variables {
    return $_[0]->{ _VARIABLES };
}

#------------------------------------------------------------------------
# process($context)
#
# Process the document in a particular context.  Checks for recursion,
# registers the document with the context via visit(), processes itself,
# and then unwinds with a large gin and tonic.
#------------------------------------------------------------------------

sub process {
    my ($self, $context) = @_;
    my $defblocks = $self->{ _DEFBLOCKS };
    my $output;


    # check we're not already visiting this template
    return $context->throw(Template::Constants::ERROR_FILE,
                           "recursion into '$self->{ name }'")
        if $self->{ _HOT } && ! $context->{ RECURSION };   ## RETURN ##

    $context->visit($self, $defblocks);

    $self->{ _HOT } = 1;
    eval {
        my $block = $self->{ _BLOCK };
        $output = &$block($context);
    };
    $self->{ _HOT } = 0;

    $context->leave();

    die $context->catch($@)
        if $@;

    return $output;
}


#------------------------------------------------------------------------
# AUTOLOAD
#
# Provides pseudo-methods for read-only access to various internal
# members.
#------------------------------------------------------------------------

sub AUTOLOAD {
    my $self   = shift;
    my $method = $AUTOLOAD;

    $method =~ s/.*:://;
    return if $method eq 'DESTROY';
#    my ($pkg, $file, $line) = caller();
#    print STDERR "called $self->AUTOLOAD($method) from $file line $line\n";
    return $self->{ $method };
}


#========================================================================
#                     -----  PRIVATE METHODS -----
#========================================================================


#------------------------------------------------------------------------
# _dump()
#
# Debug method which returns a string representing the internal state
# of the object.
#------------------------------------------------------------------------

sub _dump {
    my $self = shift;
    my $dblks;
    my $output = "$self : $self->{ name }\n";

    $output .= "BLOCK: $self->{ _BLOCK }\nDEFBLOCKS:\n";

    if ($dblks = $self->{ _DEFBLOCKS }) {
        foreach my $b (keys %$dblks) {
            $output .= "    $b: $dblks->{ $b }\n";
        }
    }

    return $output;
}


#========================================================================
#                      ----- CLASS METHODS -----
#========================================================================

#------------------------------------------------------------------------
# as_perl($content)
#
# This method expects a reference to a hash passed as the first argument
# containing 3 items:
#     METADATA   # a hash of template metadata
#     BLOCK      # string containing Perl sub definition for main block
#     DEFBLOCKS  # hash containing further subs for addional BLOCK defs
# It returns a string containing Perl code which, when evaluated and
# executed, will instantiate a new Template::Document object with the
# above data.  On error, it returns undef with an appropriate error
# message set in $ERROR.
#------------------------------------------------------------------------

sub as_perl {
    my ($class, $content) = @_;
    my ($block, $defblocks, $metadata) = @$content{ qw( BLOCK DEFBLOCKS METADATA ) };

    $block =~ s/\s+$//;

    $defblocks = join('', map {
        my $code = $defblocks->{ $_ };
        $code =~ s/\s*$//;
        "        '$_' => $code,\n";
    } keys %$defblocks);
    $defblocks =~ s/\s+$//;

    $metadata = join('', map {
        my $x = $metadata->{ $_ };
        $x =~ s/(['\\])/\\$1/g;
        "        '$_' => '$x',\n";
    } keys %$metadata);
    $metadata =~ s/\s+$//;

    return <
#------------------------------------------------------------------------
# Compiled template generated by the Template Toolkit version $Template::VERSION
#------------------------------------------------------------------------

$class->new({
    METADATA => {
$metadata
    },
    BLOCK => $block,
    DEFBLOCKS => {
$defblocks
    },
});
EOF
}


#------------------------------------------------------------------------
# write_perl_file($filename, \%content)
#
# This method calls as_perl() to generate the Perl code to represent a
# compiled template with the content passed as the second argument.
# It then writes this to the file denoted by the first argument.
#
# Returns 1 on success.  On error, sets the $ERROR package variable
# to contain an error message and returns undef.
#------------------------------------------------------------------------

sub write_perl_file {
    my ($class, $file, $content) = @_;
    my ($fh, $tmpfile);

    return $class->error("invalid filename: $file")
        unless $file =~ /^(.+)$/s;

    eval {
        require File::Temp;
        require File::Basename;
        ($fh, $tmpfile) = File::Temp::tempfile(
            DIR => File::Basename::dirname($file)
        );
        my $perlcode = $class->as_perl($content) || die $!;

        if ($UNICODE && is_utf8($perlcode)) {
            $perlcode = "use utf8;\n\n$perlcode";
            binmode $fh, ":utf8";
        }
        print $fh $perlcode;
        close($fh);
    };
    return $class->error($@) if $@;
    return rename($tmpfile, $file)
        || $class->error($!);
}


#------------------------------------------------------------------------
# catch_warnings($msg)
#
# Installed as
#------------------------------------------------------------------------

sub catch_warnings {
    $COMPERR .= join('', @_);
}


1;

__END__