NAME Parse::BBCode - Module to turn BBCode into HTML or plain text SYNOPSIS my $p = Parse::BBCode->new({ tag_def => { url => '%{parse}s', i => '%{parse}s', b => '%{parse}s', noparse => '
%{html}s
', code => sub { my ($parser, $attr, $content, $attribute_fallback) = @_; if ($attr eq 'perl') { # use some syntax highlighter $content = highlight_perl($content); } else { $content = Parse::BBCode::escape_html($content); } "$content" }, }, tags => [qw/ i b noparse url code /], } ); my $code = 'some [b]b code[/b]'; my $parsed = $p->render($code); DESCRIPTION Note: This module is still experimental, the syntax is subject to change. I'm open for any suggestions on how to improve the syntax. I wrote this module because HTML::BBCode is not extendable (or I didn't see how) and BBCode::Parser seemed good at the first glance but has some issues, for example it says that he following bbode [code] foo [b] [/code] is invalid, while I think you should be able to write unbalanced code in code tags. The approach of Parse::BBCode is lazy parsing, so it's always parsing only one level, and depending on the definition of the tag the inner content is parsed or - e.g. in code tags - not. Also BBCode::Parser dies if you have invalid code or not-permitted tags, but in a forum you'd rather show a party parsed text then an error message. What I also wanted is an easy syntax to define own tags, ideally - for simple tags - as plain text, so you can put it in a configuration file. This allows forum admins to add tags easily. Some forums might want a tag for linking to perlmonks.org, other forums need other tags. Another goal was to always output a result and don't die. I might add an option which lets the parser die with unbalanced code. METHODS new Constructor. Takes a hash reference with options as an argument. tag_def See "TAG DEFINITIONS" tags an array ref which lists the allowed tag names (this way you can define more tags but allow only a part of them. If left undef it uses all tags listed in the tag_def option). parse Input: The text to parse. Returns: the parsed tree. my $tree = $parser->parse($bbcode); render Input: The text to parse Returns: the rendered text my $parsed = $parser->render($bbcode); render_tree Input: the parse tree Returns: The rendered text my $parsed = $parser->parse_tree($tree); escape_html Utility to substitute <>&"' with their HTML entities. error If the given bbcode is invalid (unbalanced or wrongly nested classes), currently Parse::BBCode::render() will either leave the invalid tags unparsed, or, if you set the option "close_open_tags", try to add closing tags. If this happened "error()" will return the invalid tag(s), otherwise false. To get the corrected bbcode (if you set "close_open_tags") you can get the tree and return the raw text from it: if ($parser->error) { my $tree = $parser->get_tree; my $corrected = $tree->raw_text; } TAG DEFINITIONS Here is an example of all the current definition possibilities: my $p = Parse::BBCode->new({ tag_def => { '' => sub { Parse::BBCode::escape_html($_[1]) }, i => '%s', b => '%{parse}s', size => '%{parse}s', url => '%{parse}s', wikipedia => '%{parse}s', noparse => '
%{html}s
', code => { code => sub { my ($parser, $attr, $content, $attribute_fallback) = @_; if ($attr eq 'perl') { # use some syntax highlighter $content = highlight_perl($content); } else { $content = Parse::BBCode::escape_html($content); } "$content" }, parse => 0, }, }, tags => [qw/ i b size url wikipedia noparse code /], } ); The following list explains the above tag definitions: empty string This defines how plain text should be rendered: '' => sub { Parse::BBCode::escape_html($_[1]) } In the most cases, you would want HTML escaping like shown above. This is the default, so you can leave it out. Only if you want to render BBCode into plain text or something else, you need this option. i i => '%s' [i] italic [/i] turns out as italic <html> So %s stands for the tag content. By default, it is parsed itself, so that you can nest tags. b b => '%{parse}s' [b] bold [/b] turns out as bold <html> "%{parse}s" is the same as %s as 'parse' is the default. size size => '%{parse}s' [size=7] some big text [/size] turns out as some big text [/size] So %a stands for the tag attribute. By default it will be HTML escaped. url url => '%{parse}s' Here you can see how to apply a special escape. The attribute defined with "%{URL}a" is checked for a valid URL. "javascript:" will be filtered. [url=/foo.html]a link[/url] turns out as a link Note that a tag like [url]http://some.link.example[/url] will turn out as http://some.link.example In the cases where the attribute should be the same as the content you should use %A instead of %a which takes the content as the attribute as a fallback. You probably need this in all url-like tags. url => '%{parse}s', wikipedia You might want to define your own urls, e.g. for wikipedia references: wikipedia => '%{parse}s', "%{uri}A" will uri-encode the searched term: [wikipedia]Harold & Maude[/wikipedia] [wikipedia="Harold & Maude"]a movie[/wikipedia] turns out as Harold & Maude a movie noparse Sometimes you need to display verbatim bbcode. The simplest form would be a noparse tag: noparse => '
%{html}s
' [noparse] [some]unbalanced[/foo] [/noparse] With this definition the output would be 
[some]unbalanced[/foo]
So inside a noparse tag you can write (almost) any invalid bbcode. The only exception is the noparse tag itself: [noparse] [some]unbalanced[/foo] [/noparse] [b]really bold[/b] [/noparse] Output: [some]unbalanced[/foo] really bold [/noparse] Because the noparse tag ends at the first closing tag, even if you have an additional opening noparse tag inside. The "%{html}s" defines that the content should be HTML escaped. If you don't want any escaping you can't say %s because the default is 'parse'. In this case you have to write "%{noescape}". code All these definitions might not be enough if you want to define your own code, for example to add a syntax highlighter. Here's an example: code => { code => sub { my ($parser, $attr, $content, $attribute_fallback) = @_; if ($attr eq 'perl') { # use some syntax highlighter $content = highlight_perl($$content); } else { $content = Parse::BBCode::escape_html($$content); } "$content" }, parse => 0, }, So instead of a string you define a hash reference with a 'code' key and a sub reference. The other key is "parse" which is 0 by default. If it is 0 the content in the tag won't be parsed, just as in the noparse tag above. If it is set to 1 you will get the rendered content as an argument to the subroutine. The first argument to the subroutine is the Parse::BBCode object itself. The second argument is the attribute, the third the tag content as a scalar reference and the fourth argument is the attribute fallback which is set to the content if the attribute is empty. The fourth argument is just for convenience. TODO Possibility to define which urls accepted, add some default tags. REQUIREMENTS perl >= 5.6.1, Class::Accessor::Fast, URI::Escape AUTHOR Tina Mueller CREDITS Thanks to Moritz Lenz for his suggestions about the implementation and the test cases. COPYRIGHT AND LICENSE Copyright (C) 2008 by Tina Mueller This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.6.1 or, at your option, any later version of Perl 5 you may have available.