HTML::WikiConverter(3)

NAME
HTML::WikiConverter - Convert HTML to wiki markup

SYNOPSIS
  use HTML::WikiConverter;
  my $wc = new HTML::WikiConverter( dialect => 'MediaWiki' );
  print $wc->html2wiki( html => '<b>text</b>' ), "\n\n";

  # A more complete example

  my $html = qq(
    <p><i>Italic</i>, <b>bold</b>, <span style="font-weight:bold">also bold</span>, etc.</p>
  );

  my @dialects = HTML::WikiConverter->available_dialects;
  foreach my $dialect ( @dialects ) {
    my $wc = new HTML::WikiConverter( dialect => $dialect );
    my $wiki = $wc->html2wiki( html => $html );
    printf "The %s dialect gives:\n\n%s\n\n", $dialect, $wiki;
  }

DESCRIPTION
"HTML::WikiConverter" is an HTML to wiki converter. It can convert HTML source into a variety of wiki markups, called wiki "dialects". The following dialects are supported:

  DokuWiki
  Kwiki
  MediaWiki
  MoinMoin
  Oddmuse
  PbWiki
  PhpWiki
  PmWiki
  SlipSlap
  TikiWiki
  UseMod
  WakkaWiki
  WikkaWiki

Note that while dialects usually produce satisfactory wiki markup, not all features of all dialects are supported. Consult individual dialects' documentation for details of supported features. Suggestions for improvements, especially in the form of patches, are very much appreciated.

METHODS

  new
  my $wc = new HTML::WikiConverter( dialect => $dialect, %attrs );

Returns a converter for the specified wiki dialect. Croaks if $dialect is not provided or its dialect module is not installed on your system. Additional attributes may be specified in %attrs; see "ATTRIBUTES" for a complete list.

  html2wiki
  $wiki = $wc->html2wiki( $html, %attrs );
  $wiki = $wc->html2wiki( html => $html, %attrs );
  $wiki = $wc->html2wiki( file => $file, %attrs );
  $wiki = $wc->html2wiki( uri => $uri, %attrs );

Converts HTML source to wiki markup for the current dialect. Accepts either an HTML string $html, an file $file, or a URI <$uri> to read from.

Attributes assigned in %attrs (see "ATTRIBUTES") will augment or override previously assigned attributes for the duration of the html2wiki() call.

  elem_search_lineage
  my $ancestor = $wc->elem_search_lineage( $node, \%rules );

Searches the lineage of $node and returns the first ancestor node that has rules matching those specified in %rules, or "undef" if no matching node is found.

For example, to find out whether $node has an ancestor with rules matching "{ block =>1 }", one could use:

  if( $wc->elem_search_lineage( $node, { block => 1 } ) ) {
    # do something
  }

  given_html
  my $html = $wc->given_html;

Returns the HTML passed to or fetched (ie, from a file or URI) by the last html2wiki() method call. Useful for debugging.

  parsed_html
  my $parsed_html = $wc->parsed_html;

Returns a string containing the post-processed HTML from the last "html2wiki" call. Post-processing includes parsing by HTML::TreeBuilder, CSS normalization by HTML::WikiConverter::Normalizer, and calls to the "preprocess" and "preprocess_tree" dialect methods.

  available_dialects
  my @dialects = HTML::WikiConverter->available_dialects;

Returns a list of all available dialects by searching the directories in @INC for "HTML::WikiConverter::" modules.

  rules_for_tag
  my $rules = $wc->rules_for_tag( $tag );

Returns the rules that will be used for converting elements of the given tag. Follows "alias" references. Note that the rules used for a particular tag may depend on the current set of attributes being used.

ATTRIBUTES
You may configure "HTML::WikiConverter" using a number of attributes. These may be passed as arguments to the "new" constructor, or can be called as object methods on an H::WC object.

Some dialects allow other attributes in addition to those below, and may override the attributes' default values. Consult the dialect's documentation for details.

  base_uri
URI to use for converting relative URIs to absolute ones. This effectively ensures that the "src" and "href" attributes of image and anchor tags, respectively, are absolute before converting the HTML to wiki markup, which is necessary for wiki dialects that handle internal and external links separately. Relative URIs are only converted to absolute ones if the "base_uri" argument is present. Defaults to "undef".

  dialect
(Required) Dialect to use for converting HTML into wiki markup. See the "DESCRIPTION" section above for a list of dialects. new() will fail if the dialect given is not installed on your system. Use available_dialects() to list installed dialects.

  encoding
Specifies the encoding used by the HTML to be converted. Also determines the encoding of the wiki markup returned by the "html2wiki" method. Defaults to "utf8".

  escape_entities
Passing "escape_entities" a true value uses HTML::Entities to encode potentially unsafe '<', '>', and '&' characters. Defaults to true.

  p_strict
Boolean indicating whether HTML::TreeBuilder will use strict handling of paragraph tags when parsing HTML input. (This corresponds to the "p_strict" method in the HTML::TreeBuilder module.) Enabled by default.

  passthrough_naked_tags
Boolean indicating whether tags with no attributes ("naked" tags) should be removed and replaced with their content. By default, this only applies to non-semantic tags such as <span>, <div>, etc., but does not apply to semantic tags such as <strong>, <address>, etc. To override this behavior and specify the tags that should be considered for passthrough, provide this attribute with a reference to an array of tag names. Defaults to false, but you'll probably want to enable it.

  preprocess
Code reference that gets invoked after HTML is parsed but before it is converted into wiki markup. The callback is passed two arguments: the "HTML::WikiConverter" object and a HTML::Element pointing to the root node of the HTML tree created by HTML::TreeBuilder.

  slurp
Boolean that, if enabled, bypasses "HTML::Parser"'s incremental parsing (thus slurping the file in all at once) of files when reading HTML files. If File::Slurp is installed, its read_file() function will be used to perform slurping; otherwise, a common Perl idiom will be used for slurping instead. This option is only used if you call html2wiki() with the "file" argument.

  strip_empty_tags
Strips elements containing no content (unless those elements legitimately contain no content, such as is the case for "br" and "img" tags, for example). Defaults to false.

  strip_tags
A reference to an array of tags to be removed from the HTML input prior to conversion to wiki markup. Tag names are the same as those used in HTML::Element. Defaults to "[ '~comment', 'head', 'script', 'style' ]".

  user_agent
Specifies the LWP::UserAgent object to be used when fetching the URI passed to html2wiki(). If unspecified and html2wiki() is passed a URI, a default user agent will be created.

  wiki_uri
Takes a URI, regular expression, or coderef (or a reference to an array of elements of these types) used to determine which links are to wiki pages: a link whose "href" parameter matches "wiki_uri" will be treated as a link to a wiki page. In addition, "wiki_uri" will be used to extract the title of the wiki page. The way this is done depends on whether the "wiki_uri" has been set to a string, regexp, or coderef. The default is "undef", meaning that all links will be treated as external links by default.

If "wiki_uri" is a string, it is interpreted as a URI template, and it will be assumed that URIs to wiki pages are created by joining "wiki_uri" with the wiki page title. For example, the English Wikipedia might use "http://en.wikipedia.org/wiki/" as the value of "wiki_uri". Ward's wiki might use "http://c2.com/cgi/wiki?". These examples use an absolute "wiki_uri", but a relative URI can be used as well; an absolute URI will be created based on the value of "base_uri". For example, the Wikipedia example above can be rewritten using "base_uri" of "http://en.wikipedia.org" and a "wiki_uri" of "/wiki/".

"wiki_uri" can also be a regexp that matches URIs to wiki pages and also extracts the page title from them. For example, the English Wikipedia might use "qr~http://en\.wikipedia\.org/w/index\.php\?title\=([^&]+)~".

"wiki_uri" can also be a coderef that takes the current "HTML::WikiConverter" object and a URI object. It should return the title of the wiki page extracted from the URI, or "undef" if the URI doesn't represent a link to a wiki page.

As mentioned above, the "wiki_uri" attribute can either take a single URI/regexp/coderef element or it may be assigned a reference to an array of any number of these elements. This is useful for wikis that have different ways of creating links to wiki pages. For example, the English Wikipedia might use:

  my $wc = new HTML::WikiConverter(
    dialect => 'MediaWiki',
    wiki_uri => [
      'http://en.wikipiedia.org/wiki/',
      sub { pop->query_param('title') } # requires URI::QueryParam
    ]
  );

  wrap_in_html
Helps HTML::TreeBuilder parse HTML fragments by wrapping HTML in "<html>" and "</html>" before passing it through "html2wiki". Boolean, enabled by default.

ADDING A DIALECT
Consult HTML::WikiConverter::Dialects for documentation on how to write your own dialect module for "HTML::WikiConverter". Or if you're not up to the task, drop me an email and I'll have a go at it when I get a spare moment.

SEE ALSO
HTML::Tree, Convert::Wiki

AUTHOR
David J. Iberri, "<diberri@cpan.org>"

BUGS
Please report any bugs or feature requests to "bug-html-wikiconverter at rt.cpan.org", or through the web interface at <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=HTML-WikiConverter>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT
You can find documentation for this module with the perldoc command.

    perldoc HTML::WikiConverter

You can also look for information at:

•   AnnoCPAN: Annotated CPAN documentation

    <http://annocpan.org/dist/HTML-WikiConverter>

•   CPAN Ratings

    <http://cpanratings.perl.org/d/HTML-WikiConverter>

•   RT: CPAN's request tracker

    <http://rt.cpan.org/NoAuth/Bugs.html?Dist=HTML-WikiConverter>

•   Search CPAN

    <http://search.cpan.org/dist/HTML-WikiConverter>

ACKNOWLEDGEMENTS
Thanks to Tatsuhiko Miyagawa for suggesting Bundle::HTMLWikiConverter as well as providing code for the available_dialects() class method.

My thanks also goes to Martin Kudlvasr for catching (and fixing!) a bug in the logic of how HTML files were processed.

Big thanks to Dave Schaefer for the PbWiki dialect and for the idea behind the new attributes() implementation.

COPYRIGHT & LICENSE
Copyright (c) David J. Iberri, all rights reserved.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.