Module: MetaTags::TextNormalizer

Extended by:
TextNormalizer
Included in:
TextNormalizer
Defined in:
lib/meta_tags/text_normalizer.rb

Overview

This module contains helpers that normalize text meta tag values.

Instance Method Summary collapse

Instance Method Details

#cleanup_string(string, strip: true) ⇒ String

Removes HTML tags and squashes down all the spaces.

Parameters:

  • string (String, nil) —

    input string.

  • strip (Boolean) (defaults to: true) —

    whether to trim leading and trailing whitespace.

Returns:

  • (String) —

    input string with no HTML tags and consecutive whitespace characters squashed into a single space.

Raises:

  • (ArgumentError) 


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# File 'lib/meta_tags/text_normalizer.rb', line 103

def cleanup_string(string, strip: true)
  return "" if string.nil?
  raise ArgumentError, "Expected a string or an object that implements #to_str" unless string.respond_to?(:to_str)

  s = strip_tags(string.to_str)
  s = s.dup if s.frozen?
  s.gsub!(/\s+/, " ")
  s.strip! if strip

  s
end

#cleanup_strings(strings, strip: true) ⇒ Array<String>

Cleans up multiple strings.

Parameters:

  • strings (String, Array<String>) —

    input string(s).

  • strip (Boolean) (defaults to: true) —

    whether to trim leading and trailing whitespace.

Returns:

  • (Array<String>) —

    clean strings.

See Also:



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# File 'lib/meta_tags/text_normalizer.rb', line 121

def cleanup_strings(strings, strip: true)
  strings = Array(strings).flatten.map! { |s| cleanup_string(s, strip: strip) }
  strings.reject!(&:blank?)
  strings
end

#helpers ⇒ ActionView::Base

Easy way to get access to Rails helpers.

Returns:

  • (ActionView::Base) —

    proxy object to access Rails helpers.



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# File 'lib/meta_tags/text_normalizer.rb', line 68

def helpers
  ActionController::Base.helpers
end

#normalize_description(description) ⇒ String

Normalize description value.

Parameters:

  • description (String) —

    description string.

Returns:

  • (String) —

    text with tags removed, squashed spaces, and truncated to the configured description limit.



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# File 'lib/meta_tags/text_normalizer.rb', line 40

def normalize_description(description)
  # description could be another object not a string, but since it probably
  # serves the same purpose, we can ask it to convert itself to a string
  # and continue from there
  description = cleanup_string(description)
  return "" if description.blank?

  truncate(description, MetaTags.config.description_limit)
end

#normalize_keywords(keywords) ⇒ String

Normalize keywords value.

Parameters:

  • keywords (String, Array<String>) —

    list of keywords as a string or Array.

Returns:

  • (String) —

    list of keywords joined with comma, with tags removed.



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# File 'lib/meta_tags/text_normalizer.rb', line 54

def normalize_keywords(keywords)
  keywords = cleanup_strings(keywords)
  return "" if keywords.blank?

  keywords.each(&:downcase!) if MetaTags.config.keywords_lowercase
  separator = cleanup_string MetaTags.config.keywords_separator, strip: false

  keywords = truncate_array(keywords, MetaTags.config.keywords_limit, separator)
  safe_join(keywords, separator)
end

#normalize_title(site_title, title, separator, reverse = false) ⇒ String

Normalize title value.

Parameters:

  • site_title (String) —

    site title.

  • title (Array<String>) —

    title segments.

  • separator (String) —

    a string to join title parts with.

  • reverse (Boolean) (defaults to: false) —

    whether title should be reversed.

Returns:

  • (String) —

    title with HTML tags removed.



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# File 'lib/meta_tags/text_normalizer.rb', line 15

def normalize_title(site_title, title, separator, reverse = false)
  clean_title = cleanup_strings(title)
  clean_title.reverse! if reverse

  site_title = cleanup_string(site_title)
  separator = cleanup_string(separator, strip: false)

  # Truncate title and site title
  site_title, clean_title = truncate_title(site_title, clean_title, separator)

  if site_title.present?
    if reverse
      clean_title.push(site_title)
    else
      clean_title.unshift(site_title)
    end
  end
  safe_join(clean_title, separator)
end

#safe_join(array, sep = $OFS) ⇒ String

This method returns an HTML-safe string similar to what Array#join would return. All items in the array, including the supplied separator, are HTML-escaped unless they are HTML-safe, and the returned string is marked as HTML-safe.

Parameters:

  • array (Array<String>) —

    list of strings to join.

  • sep (String) (defaults to: $OFS) —

    separator to join strings with.

Returns:

  • (String) —

    input strings joined together using a given separator.



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# File 'lib/meta_tags/text_normalizer.rb', line 93

def safe_join(array, sep = $OFS)
  helpers.safe_join(array, sep)
end

#strip_tags(string) ⇒ String

Strips all HTML tags from string, including comments.

Parameters:

  • string (String) —

    HTML string.

Returns:

  • (String) —

    HTML-safe string with no HTML tags.



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# File 'lib/meta_tags/text_normalizer.rb', line 76

def strip_tags(string)
  if defined?(Loofah)
    # Instead of strip_tags we will use Loofah to strip tags from now on
    Loofah.fragment(string).text(encode_special_chars: false)
  else
    helpers.strip_tags(string)
  end
end

#truncate(string, limit = nil) ⇒ String

Truncates a string to a specific limit. Returns the string without truncation when the limit is 0 or nil.

Parameters:

  • string (String) —

    input string.

  • limit (Integer, nil) (defaults to: nil) —

    number of characters to truncate to.

Returns:

  • (String) —

    truncated string.



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# File 'lib/meta_tags/text_normalizer.rb', line 133

def truncate(string, limit = nil)
  return string if limit.to_i == 0

  helpers.truncate(
    string,
    length: limit,
    separator: MetaTags.config.truncate_on_natural_separator,
    omission: "",
    escape: true
  )
end

#truncate_array(string_array, limit = nil, separator = "") ⇒ Array<String>

Truncates an array of strings to a specific limit.

Parameters:

  • string_array (Array<String>) —

    input strings.

  • limit (Integer, nil) (defaults to: nil) —

    number of characters to truncate to.

  • separator (String) (defaults to: "") —

    separator that will be used to join the array later.

Returns:

  • (Array<String>) —

    truncated array of strings.



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# File 'lib/meta_tags/text_normalizer.rb', line 151

def truncate_array(string_array, limit = nil, separator = "")
  return string_array if limit.nil? || limit <= 0

  length = 0
  result = [] # : Array[String]

  string_array.each do |string|
    limit_left = calculate_limit_left(limit, length, result, separator)

    if string.length > limit_left
      result << truncate(string, limit_left)
      break string_array
    end

    length += (result.any? ? separator.length : 0) + string.length
    result << string

    # No more strings will fit
    break string_array if length + separator.length >= limit
  end

  result
end