module CGI::Util

Constants

RFC822_DAYS

Abbreviated day-of-week names specified by RFC 822

RFC822_MONTHS

Abbreviated month names specified by RFC 822

TABLE_FOR_ESCAPE_HTML__

The set of special characters and their escaped values

Public Instance Methods

escape(string) click to toggle source

URL-encode a string.

url_encoded_string = CGI::escape("'Stop!' said Fred")
   # => "%27Stop%21%27+said+Fred"
# File lib/cgi/util.rb, line 11
def escape(string)
  encoding = string.encoding
  string.b.gsub(/([^ a-zA-Z0-9_.-]+)/) do |m|
    '%' + m.unpack('H2' * m.bytesize).join('%').upcase
  end.tr(' ', '+').force_encoding(encoding)
end
escapeElement(string, *elements) click to toggle source

Escape only the tags of certain HTML elements in string.

Takes an element or elements or array of elements. Each element is specified by the name of the element, without angle brackets. This matches both the start and the end tag of that element. The attribute list of the open tag will also be escaped (for instance, the double-quotes surrounding attribute values).

print CGI::escapeElement('<BR><A HREF="url"></A>', "A", "IMG")
  # "<BR>&lt;A HREF=&quot;url&quot;&gt;&lt;/A&gt"

print CGI::escapeElement('<BR><A HREF="url"></A>', ["A", "IMG"])
  # "<BR>&lt;A HREF=&quot;url&quot;&gt;&lt;/A&gt"
# File lib/cgi/util.rb, line 139
def escapeElement(string, *elements)
  elements = elements[0] if elements[0].kind_of?(Array)
  unless elements.empty?
    string.gsub(/<\/?(?:#{elements.join("|")})(?!\w)(?:.|\n)*?>/i) do
      CGI::escapeHTML($&)
    end
  else
    string
  end
end
Also aliased as: escape_element
escapeHTML(string) click to toggle source

Escape special characters in HTML, namely '&"<>

CGI::escapeHTML('Usage: foo "bar" <baz>')
   # => "Usage: foo &quot;bar&quot; &lt;baz&gt;"
# File lib/cgi/util.rb, line 40
def escapeHTML(string)
  enc = string.encoding
  unless enc.ascii_compatible?
    if enc.dummy?
      origenc = enc
      enc = Encoding::Converter.asciicompat_encoding(enc)
      string = enc ? string.encode(enc) : string.b
    end
    table = Hash[TABLE_FOR_ESCAPE_HTML__.map {|pair|pair.map {|s|s.encode(enc)}}]
    string = string.gsub(/#{"['&\"<>]".encode(enc)}/, table)
    string.encode!(origenc) if origenc
    return string
  end
  string.gsub(/['&\"<>]/, TABLE_FOR_ESCAPE_HTML__)
end
Also aliased as: escape_html, h
escape_element(string, *elements)

Synonym for CGI::escapeElement(str)

Alias for: escapeElement
escape_html(string)

Synonym for CGI::escapeHTML(str)

Alias for: escapeHTML
h(string)
Alias for: escapeHTML
pretty(string, shift = " ") click to toggle source

Prettify (indent) an HTML string.

string is the HTML string to indent. shift is the indentation unit to use; it defaults to two spaces.

print CGI::pretty("<HTML><BODY></BODY></HTML>")
  # <HTML>
  #   <BODY>
  #   </BODY>
  # </HTML>

print CGI::pretty("<HTML><BODY></BODY></HTML>", "\t")
  # <HTML>
  #         <BODY>
  #         </BODY>
  # </HTML>
# File lib/cgi/util.rb, line 210
def pretty(string, shift = "  ")
  lines = string.gsub(/(?!\A)<.*?>/m, "\n\\0").gsub(/<.*?>(?!\n)/m, "\\0\n")
  end_pos = 0
  while end_pos = lines.index(/^<\/(\w+)/, end_pos)
    element = $1.dup
    start_pos = lines.rindex(/^\s*<#{element}/i, end_pos)
    lines[start_pos ... end_pos] = "__" + lines[start_pos ... end_pos].gsub(/\n(?!\z)/, "\n" + shift) + "__"
  end
  lines.gsub(/^((?:#{Regexp::quote(shift)})*)__(?=<\/?\w)/, '\1')
end
rfc1123_date(time) click to toggle source

Format a Time object as a String using the format specified by RFC 1123.

CGI::rfc1123_date(Time.now)
  # Sat, 01 Jan 2000 00:00:00 GMT
# File lib/cgi/util.rb, line 186
def rfc1123_date(time)
  t = time.clone.gmtime
  return format("%s, %.2d %s %.4d %.2d:%.2d:%.2d GMT",
                RFC822_DAYS[t.wday], t.day, RFC822_MONTHS[t.month-1], t.year,
                t.hour, t.min, t.sec)
end
unescape(string,encoding=@@accept_charset) click to toggle source

URL-decode a string with encoding(optional).

string = CGI::unescape("%27Stop%21%27+said+Fred")
   # => "'Stop!' said Fred"
# File lib/cgi/util.rb, line 21
def unescape(string,encoding=@@accept_charset)
  str=string.tr('+', ' ').b.gsub(/((?:%[0-9a-fA-F]{2})+)/) do |m|
    [m.delete('%')].pack('H*')
  end.force_encoding(encoding)
  str.valid_encoding? ? str : str.force_encoding(string.encoding)
end
unescapeElement(string, *elements) click to toggle source

Undo escaping such as that done by CGI::escapeElement()

print CGI::unescapeElement(
        CGI::escapeHTML('<BR><A HREF="url"></A>'), "A", "IMG")
  # "&lt;BR&gt;<A HREF="url"></A>"

print CGI::unescapeElement(
        CGI::escapeHTML('<BR><A HREF="url"></A>'), ["A", "IMG"])
  # "&lt;BR&gt;<A HREF="url"></A>"
# File lib/cgi/util.rb, line 159
def unescapeElement(string, *elements)
  elements = elements[0] if elements[0].kind_of?(Array)
  unless elements.empty?
    string.gsub(/&lt;\/?(?:#{elements.join("|")})(?!\w)(?:.|\n)*?&gt;/i) do
      unescapeHTML($&)
    end
  else
    string
  end
end
Also aliased as: unescape_element
unescapeHTML(string) click to toggle source

Unescape a string that has been HTML-escaped

CGI::unescapeHTML("Usage: foo &quot;bar&quot; &lt;baz&gt;")
   # => "Usage: foo \"bar\" <baz>"
# File lib/cgi/util.rb, line 64
def unescapeHTML(string)
  enc = string.encoding
  unless enc.ascii_compatible?
    if enc.dummy?
      origenc = enc
      enc = Encoding::Converter.asciicompat_encoding(enc)
      string = enc ? string.encode(enc) : string.b
    end
    string = string.gsub(Regexp.new('&(apos|amp|quot|gt|lt|#[0-9]+|#x[0-9A-Fa-f]+);'.encode(enc))) do
      case $1.encode(Encoding::US_ASCII)
      when 'apos'                then "'".encode(enc)
      when 'amp'                 then '&'.encode(enc)
      when 'quot'                then '"'.encode(enc)
      when 'gt'                  then '>'.encode(enc)
      when 'lt'                  then '<'.encode(enc)
      when /\A#0*(\d+)\z/        then $1.to_i.chr(enc)
      when /\A#x([0-9a-f]+)\z/i  then $1.hex.chr(enc)
      end
    end
    string.encode!(origenc) if origenc
    return string
  end
  return string unless string.include? '&'
  charlimit = case enc
              when Encoding::UTF_8; 0x10ffff
              when Encoding::ISO_8859_1; 256
              else 128
              end
  string.gsub(/&(apos|amp|quot|gt|lt|\#[0-9]+|\#[xX][0-9A-Fa-f]+);/) do
    match = $1.dup
    case match
    when 'apos'                then "'"
    when 'amp'                 then '&'
    when 'quot'                then '"'
    when 'gt'                  then '>'
    when 'lt'                  then '<'
    when /\A#0*(\d+)\z/
      n = $1.to_i
      if n < charlimit
        n.chr(enc)
      else
        "&##{$1};"
      end
    when /\A#x([0-9a-f]+)\z/i
      n = $1.hex
      if n < charlimit
        n.chr(enc)
      else
        "&#x#{$1};"
      end
    else
      "&#{match};"
    end
  end
end
Also aliased as: unescape_html
unescape_element(string, *elements)

Synonym for CGI::unescapeElement(str)

Alias for: unescapeElement
unescape_html(string)

Synonym for CGI::unescapeHTML(str)

Alias for: unescapeHTML