Class: HTMLPipeline::NodeFilter::MentionFilter

Inherits:
HTMLPipeline::NodeFilter show all
Defined in:
lib/html_pipeline/node_filter/mention_filter.rb

Overview

HTML filter that replaces @user mentions with links. Mentions within <pre>, <code>, and <a> elements are ignored. Mentions that reference users that do not exist are ignored.

Context options:

:base_url - Used to construct links to user profile pages for each
            mention.
:info_url - Used to link to "more info" when someone mentions @mention
            or @mentioned.
:username_pattern - Used to provide a custom regular expression to
                    identify usernames

Constant Summary collapse

MENTION_PATTERNS =

Hash that contains all of the mention patterns used by the pipeline

Hash.new do |hash, key|
  hash[key] = %r{
    (?:^|\W)                    # beginning of string or non-word char
    @((?>#{key}))  # @username
    (?!/)                      # without a trailing slash
    (?=
      \.+[ \t\W]|               # dots followed by space or non-word character
      \.+$|                     # dots at end of line
      [^0-9a-zA-Z_.]|           # non-word character except dot
      $                         # end of line
    )
  }ix
end
USERNAME_PATTERN =

Default pattern used to extract usernames from text. The value can be overriden by providing the username_pattern variable in the context.

/[a-z0-9][a-z0-9-]*/
IGNORE_PARENTS =

Don’t look for mentions in text nodes that are children of these elements

["pre", "code", "a", "style", "script"]
SELECTOR = 
Selma::Selector.new(match_text_within: "*", ignore_text_within: IGNORE_PARENTS)

Instance Attribute Summary

Attributes inherited from HTMLPipeline::NodeFilter

#context

Attributes inherited from Filter

#context, #result

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from HTMLPipeline::NodeFilter

call, #html, #initialize, #reset!

Methods inherited from Filter

#base_url, #call, call, #has_ancestor?, #initialize, #needs, #validate

Constructor Details

This class inherits a constructor from HTMLPipeline::NodeFilter

Class Method Details

.mentioned_logins_in(text, username_pattern = USERNAME_PATTERN) ⇒ Object

Public: Find user @mentions in text. See MentionFilter#mention_link_filter.

MentionFilter.mentioned_logins_in(text) do |match, , is_mentioned|
  "<a href=...>#{}</a>"
end

text - String text to search.

Yields the String match, the String login name, and a Boolean determining if the match = “@mention”. The yield’s return replaces the match in the original text.

Returns a String replaced with the return of the block.



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 35

def mentioned_logins_in(text, username_pattern = USERNAME_PATTERN)
  text.gsub(MENTION_PATTERNS[username_pattern]) do |match|
     = Regexp.last_match(1)
    yield match, 
  end
end

Instance Method Details

#after_initialize ⇒ Object 



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 66

def after_initialize
  result[:mentioned_usernames] ||= []
end

#handle_text_chunk(text) ⇒ Object 



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 74

def handle_text_chunk(text)
  content = text.to_s
  return unless content.include?("@")

  html = mention_link_filter(content, base_url: base_url, username_pattern: username_pattern)
  return if html == content

  text.replace(html, as: :html)
end

#info_url ⇒ Object

The URL to provide when someone @mentions a “mention” name, such as @mention or @mentioned, that will give them more info on mentions.



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 86

def info_url
  context[:info_url] || nil
end

#link_to_mentioned_user(base_url, login) ⇒ Object 



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 114

def link_to_mentioned_user(base_url, )
  result[:mentioned_usernames] |= []

  url = base_url.dup
  excluded_prefixes = %r{[/(?:~|@]\z}
  url << "/" unless excluded_prefixes.match?(url)

  "<a href=\"#{url << }\" class=\"user-mention\">" \
    "@#{}" \
    "</a>"
end

#mention_link_filter(text, base_url: "/", username_pattern: USERNAME_PATTERN) ⇒ Object

Replace user @mentions in text with links to the mentioned user’s profile page.

text - String text to replace @mention usernames in. base_url - The base URL used to construct user profile URLs. info_url - The “more info” URL used to link to more info on @mentions.

If nil we don't link @mention or @mentioned.

username_pattern - Regular expression used to identify usernames in

text

Returns a string with @mentions replaced with links. All links have a ‘user-mention’ class name attached for styling.



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 106

def mention_link_filter(text, base_url: "/", username_pattern: USERNAME_PATTERN)
  self.class.mentioned_logins_in(text, username_pattern) do |match, |
    link = link_to_mentioned_user(base_url, )

    link ? match.sub("@#{}", link) : match
  end
end

#selector ⇒ Object 



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 70

def selector
  SELECTOR
end

#username_pattern ⇒ Object 



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# File 'lib/html_pipeline/node_filter/mention_filter.rb', line 90

def username_pattern
  context[:username_pattern] || USERNAME_PATTERN
end