kimihito / qiita-markdown

Qiita-specified markdown processor.

Qiita::Markdown

Qiita-specified markdown processor.

• Markdown conversion
• Sanitization
• Code and language detection
• Task list
• ToC
• Emoji
• Syntax highlighting
• Mention
• Footnotes

Basic Usage

Qiita::Markdown::Processor provides markdown rendering logic.

processor = Qiita::Markdown::Processor.new
processor.call(markdown)
# => {
#   codes: [
#     {
#       code: "1 + 1\n",
#       language: "ruby",
#       filename: "example.rb",
#     },
#   ],
#   mentioned_usernames: [
#     "alice",
#     "bob",
#   ],
#   output: "<h1>Example</h1>\n...",
# }

Filters

Qiita::Markdown is built on jch/html-pipeline. Add your favorite html-pipeline-compatible filters.

processor = Qiita::Markdown::Processor.new
processor.filters << HTML::Pipeline::ImageMaxWidthFilter
processor.call(text)

Context

.new and #call can take optional context as a Hash with following keys:

:allowed_usernames - A list of usernames allowed to be username. (Array<String>)
:asset_path        - URL path to link to emoji sprite. (String)
:asset_root        - Base URL to link to emoji sprite. (String)
:base_url          - Used to construct links to user profile pages for each. (String)
:default_language  - Default language used if no language detected from code. (String)
:language_aliases  - Alias table for some language names. (Hash)
:rule              - Sanitization rule table. (Hash)
:script            - A flag to allow to embed script element. (Boolean)

processor = Qiita::Markdown::Processor.new(asset_root: "http://example.com/assets")
processor.call(text)

Rendering Summary

There's another processor Qiita::Markdown::SummaryProcessor, which is for rendering a summary of markdown document. It simplifies a document by removing complex markups and also truncates it to a specific length without breaking the document structure.

Note that this processor does not produce the :codes output in contrast to the Processor.

Context

SummaryProcessor accepts the following context in addition to the Processor's context:

{
  truncate: {
    length: 100,  # Documents will be truncated if it exceeds this character count. (Integer)
    omission: '…' # A string added to the end of document when it's truncated. (String, nil)
  }
}

processor = Qiita::Markdown::SummaryProcessor.new(truncate: { length: 80 })
processor.call(text)