module Twitter::Validation

Constants

DEFAULT_TCO_URL_LENGTHS
MAX_LENGTH
VALID_LIST_RE

Public Instance Methods

tweet_invalid?(text) click to toggle source

Check the text for any reason that it may not be valid as a Tweet. This is meant as a pre-validation before posting to api.twitter.com. There are several server-side reasons for Tweets to fail but this pre-validation will allow quicker feedback.

Returns false if this text is valid. Otherwise one of the following Symbols will be returned:

<tt>:too_long</tt>:: if the <tt>text</tt> is too long
<tt>:empty</tt>:: if the <tt>text</tt> is nil or empty
<tt>:invalid_characters</tt>:: if the <tt>text</tt> contains non-Unicode or any of the disallowed Unicode characters
# File lib/twitter-text/validation.rb, line 47
def tweet_invalid?(text)
  return :empty if !text || text.empty?
  begin
    return :too_long if tweet_length(text) > MAX_LENGTH
    return :invalid_characters if Twitter::Regex::INVALID_CHARACTERS.any?{|invalid_char| text.include?(invalid_char) }
  rescue ArgumentError
    # non-Unicode value.
    return :invalid_characters
  end

  return false
end
tweet_length(text, options = {}) click to toggle source

Returns the length of the string as it would be displayed. This is equivilent to the length of the Unicode NFC (See: www.unicode.org/reports/tr15). This is needed in order to consistently calculate the length of a string no matter which actual form was transmitted. For example:

U+0065  Latin Small Letter E

+ U+0301 Combining Acute Accent


2 bytes, 2 characters, displayed as é (1 visual glyph)

… The NFC of {U+0065, U+0301} is {U+00E9}, which is a single chracter and a +display_length+ of 1

The string could also contain U+00E9 already, in which case the canonicalization will not change the value.

# File lib/twitter-text/validation.rb, line 25
def tweet_length(text, options = {})
  options = DEFAULT_TCO_URL_LENGTHS.merge(options)

  length = text.to_nfc.unpack("U*").length

  Twitter::Extractor.extract_urls_with_indices(text) do |url, start_position, end_position|
    length += start_position - end_position
    length += url.downcase =~ /^https:\/\// ? options[:short_url_length_https] : options[:short_url_length]
  end

  length
end
valid_hashtag?(hashtag) click to toggle source
# File lib/twitter-text/validation.rb, line 79
def valid_hashtag?(hashtag)
  return false if !hashtag || hashtag.empty?

  extracted = Twitter::Extractor.extract_hashtags(hashtag)
  # Should extract the hashtag minus the # sign, hence the [1..-1]
  extracted.size == 1 && extracted.first == hashtag[1..-1]
end
valid_list?(username_list) click to toggle source
# File lib/twitter-text/validation.rb, line 73
def valid_list?(username_list)
  match = username_list.match(VALID_LIST_RE)
  # Must have matched and had nothing before or after
  !!(match && match[1] == "" && match[4] && !match[4].empty?)
end
valid_tweet_text?(text) click to toggle source
# File lib/twitter-text/validation.rb, line 60
def valid_tweet_text?(text)
  !tweet_invalid?(text)
end
valid_url?(url, unicode_domains=true, require_protocol=true) click to toggle source
# File lib/twitter-text/validation.rb, line 87
def valid_url?(url, unicode_domains=true, require_protocol=true)
  return false if !url || url.empty?

  url_parts = url.match(Twitter::Regex[:validate_url_unencoded])
  return false unless (url_parts && url_parts.to_s == url)

  scheme, authority, path, query, fragment = url_parts.captures

  return false unless ((!require_protocol ||
                       (valid_match?(scheme, Twitter::Regex[:validate_url_scheme]) && scheme.match(/\Ahttps?\Z/i))) &&
                       valid_match?(path, Twitter::Regex[:validate_url_path]) &&
                       valid_match?(query, Twitter::Regex[:validate_url_query], true) &&
                       valid_match?(fragment, Twitter::Regex[:validate_url_fragment], true))

  return (unicode_domains && valid_match?(authority, Twitter::Regex[:validate_url_unicode_authority])) ||
         (!unicode_domains && valid_match?(authority, Twitter::Regex[:validate_url_authority]))
end
valid_username?(username) click to toggle source
# File lib/twitter-text/validation.rb, line 64
def valid_username?(username)
  return false if !username || username.empty?

  extracted = Twitter::Extractor.extract_mentioned_screen_names(username)
  # Should extract the username minus the @ sign, hence the [1..-1]
  extracted.size == 1 && extracted.first == username[1..-1]
end

Private Instance Methods

valid_match?(string, regex, optional=false) click to toggle source
# File lib/twitter-text/validation.rb, line 107
def valid_match?(string, regex, optional=false)
  return (string && string.match(regex) && $~.to_s == string) unless optional

  !(string && (!string.match(regex) || $~.to_s != string))
end