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NAME

Dancer2::Plugin::MarkdownFilesToHTML

VERSION

version 0.011

SYNOPSIS

Include the plugin in your Dancer2 app:

  use Dancer2::Plugin::MarkdownFilesToHTML;

No other perl code is necessary. Routes can be established to display the HTML associated with a directory of markdown documents or a single document using the Dancer2 config.yml file:

  plugins:
    MarkdownFilesToHTML:
      defaults:
        header_class: 'elegantshadow scrollspy'  # class added to headers
        route_root: 'tutorials'                  # where routes get attached to
        file_root: 'lib/data/markdown_files'     # location of markdown files
        generate_toc: 1                          # generate a table of contents
        linkable_headers: 1                      # create unique id for headers
        template: 'index.tt'                     # template file to use
        layout: 'main.tt'                        # layout file to use
      routes:                                    # list of conversion routes
        - dzil_tutorial:
            dir: 'Dist-Zilla-for-Beginners'      # dir containing markdown files
            markdown_extensions:
              - md
              - mdwn
        - another_tutorial:
            file: 'intro.md'                     # markdown file to be converted
            template: 'doc.tt'                   # defaults can be overridden
            generate_toc: 0
            linkable_headers: 0

See the CONFIGURATION section below for more details on configuration settings.

Conversion with Perl code can also be accomplished using the keywords provided by this is plugin, like so:

  # convert a single markdown file to HTML
  $html = mdfile_2html('/path/to/file.md', { header_class => 'header_style' });

  # convert directory of markdown files to HTML and generate table of contents
  ($html, $toc) = mdfiles_2html('/dir/with/markdown/files', { generate_toc => 1 });

DESCRIPTION

This module converts markdown files into a single HTML string using the Dancer2 web app framework. Using the Dancer2 config file, multiple routes can be established in the web app, with each route converting a single markdown document or all the markdown documents in a directory into an HTML string. Optionally, it can return a second HTML string containing a hierarchical table of contents based on the contents of the markdown documents. These strings can then be inserted into your Dancer2 website using a config file or manually using keywords. This module relies on the Text::Markdown::Hoedown module to execute the markdown conversions which uses a fast C module. To further enhance performance, a caching mechanism using Storable is employed for each converted markdown file so markdown to HTML conversions are avoided except for new and updated markdown files.

The module is particarly well-suited for markdown that follows a classic outline structure with markdown headers, like so:

  # Title of Document

  ## Header 2

  ### Header 3

  #### Header 4

  And so on...

Each header is converted to a <hX\> html tag where X is the level corresponding header level in the markdown file. If present, the headers can be used to generate the table of contents and associated anchor tags for linking to each of the sections within the document. If headers are not present in the markdown file, a useful table of contents cannot be generated.

Conversion keywords can also be called directly from within your Dancer2 app. Note that when called directly and a configuration file is also implemented, most of the default settings apply (route, template, and layout settings don't) but can also be overridden when using the keyword by passing an an optional hash reference.

KEYWORDS

mdfile_2html($file, [ \%options ])

Converts a single markdown file into HTML. An optional hashref can be passed with options as documented in the OPTIONS section below.

Example:

  my $html = mdfile_2html('/path/to/file', { header_class => 'my_style' });

If the $file argument is relative, it will be appended to the file_root setting in the configuration file. If file_root is not set in the configuration file, lib/data/markdown_files is used.

mdfiles_2html($dir, [ \%options ] )

Attempts to convert all the files present in a directory from markdown into a single HTML string.

Example:

  my ($html, $toc) = mdfiles_2html('/path/to/dir/with/makrdown/files',
                      { generate_toc => 1 });

If the $dir argument is relative, then it will be appended to the file_root setting in the configuration file. If file_root is not set in the configuration file, lib/data/markdown_files is used.

Each file can be thought of as a chapter within a single larger document comprised of all the individual files. Ideally, each file will have a single level 1 header tag to serve as the title for the chapter.

The method asssumes all files present in a directory are markdown documents. Hidden files (those beginning with a '.') are automatically excluded. These defaults can be modified.

All the "General Options" avialable to the mdfile_2html keyword apply to the mdfiles_html keyword as well. See the "Directory Options" section for more additional options that let you control how files in a directory are processed and selected.

OPTIONS

General Options

route_root => $route

The root route is the route the individual conversion routes are attached to. For example, if the root route is tutorials, a conversion route named perl will be found at tutorials/perl. If no root route is supplied, / is used.

file_root => $path

The root directory where markdown files can be found. Defaults to the lib/data/markdown_files directory within the Dancer2 web app. Directories and files supplied by each route will be relative to this path if they are relative. If directory or file path is absolute, this value is ignored.

generate_toc => $bool

A boolean value that defaults to false. If true, the function will return a second string containing a table of contents with anchor tags linking to the associated headers in the content. This setting effectively sets the linkable_headers option to true (see below).

linkable_headers => $bool

A boolean value that defaults to false. If true, a unique id is inserted into the header HTML tags so they can be linked to. Linkable headers are also generated if the toc generate_toc option is true.

header_class => $classes

Accepts a string which is added to each of the header tags' "class" attribute.

template => $template_file

The template file to use relative to directory where the app's views are store. index.tt is the default template.

layout => $layout_file

The layout file to use relative to the app's layout directory main.tt is the default layout.

cache => $bool

Stores generated html in files. If the timestamp of the cached file indicates the original file been updated, a new version of page will be generated. The cache defaults to true and there is no good reason to turn this off except to troubleshoot problems with the cache.

Directory Options

include_files => [ $file1, $file2, ... ]

An array of strings representing the files that should be converted in the order they are to be converted.

By default, the files are processed in alphabetical order. Though alphabetical ordering can be overridden manually using the include_files option, it's easier to use a naming convention for your files that will places them in the desired order:

  tutorial01.md
  tutorial02.md
  tutorial03.md
  etc.

exclude_files => [ $file1, $file2, ... ]

An array of strings represening the files that should not be converted to HTML.

markdown_extensions => [ $ext1, $ext2, ... ]

An array of strings representing the extensions that should be used to determine which files contain the markdown documents. This option is valid only with the mdfiles_2html) keyword. Only files with the listed extension will be converted.

CONFIGURATION

Though the mdfile_2html and mdfile_2html keywords can be passed arguments directly, the configuration is a more convenient way to associate routes with the HTML generatd by the converted markdown files. This makes it very easy to generate new pages on your website. Unless you need to modify the output of the HTML generated by this module in some way, we recommend using the configuration file to generate the pages.

All of the options listed above are supported by the configuration file.

The configuration settings are placed in the config.yml file usually located in the root of your Dancer2 app and begins with:

  plugins:
    MarkdownFiletoHTML:

Follow these two lines with your default settings:

      defaults:
        header_class: 'my_header classes here'
        route_root: 'content'
        file_root: '/lib/data/content'
        genereate_toc: 1

...and so on.

After the defaults, you can list your routes:

       routes:
         - a_web_page:
           dir: 'convert/all/files/in/this/dir/relative/to/file_root'
         - another_web_page:
           file: '/convert/this/file/with/absolute/path.md'

Routes must have either a dir or file property. Relative paths are relative to the file_root default.

The default options can be overridden for each route like so:

       routes:
         - my_page
           file: 'file.md'
           toc: 0
           header_class: ''

Consult the #Options section for defaults for each of the options.

The options that apply to directories accept a list of arguments, created like this:

        routes:
          - another_page:
            dir: 'my_dir_containing_md_file'
            include_files:
              - 'file4.md'
              - 'file2.md'
              - 'file1.md'
              - 'file3.md'

Now only the four files listed get processed in the order listed above.

MARKDOWN CONVERSION NOTES

The module aims to support the dialect of markdown as implemented by GitHub with strikethroughs (~~strike~~) and "fenced" code (```fenced code```). This module may make the dialect options configurable in the future.

The module will add a "single-line" class to single lines of code to facility additional styling.

REQUIRES

SUPPORT

Perldoc

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

  perldoc Dancer2::Plugin::MarkdownFilesToHTML

Websites

The following websites have more information about this module, and may be of help to you. As always, in addition to those websites please use your favorite search engine to discover more resources.

Source Code

The code is open to the world, and available for you to hack on. Please feel free to browse it and play with it, or whatever. If you want to contribute patches, please send me a diff or prod me to pull from your repository :)

https://github.com/sdondley/Dancer2-Plugin-MarkdownFilesToHTML

  git clone git://github.com/sdondley/Dancer2-Plugin-MarkdownFilesToHTML.git

BUGS AND LIMITATIONS

You can make new bug reports, and view existing ones, through the web interface at https://github.com/sdondley/Dancer2-Plugin-MarkdownFilesToHTML/issues.

INSTALLATION

See perlmodinstall for information and options on installing Perl modules.

SEE ALSO

Dancer2

Text::Markup::Hoedown

AUTHOR

Steve Dondley <s@dondley.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2018 by Steve Dondley.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.