Module: Rack::Utils

Defined in:
lib/gems/rack-0.9.1/lib/rack/utils.rb

Overview

Rack::Utils contains a grab-bag of useful methods for writing web applications adopted from all kinds of Ruby libraries.

Defined Under Namespace

Modules: Multipart Classes: Context, HeaderHash

Constant Summary collapse

HTTP_STATUS_CODES =

Every standard HTTP code mapped to the appropriate message. Stolen from Mongrel.

{
  100  => 'Continue',
  101  => 'Switching Protocols',
  200  => 'OK',
  201  => 'Created',
  202  => 'Accepted',
  203  => 'Non-Authoritative Information',
  204  => 'No Content',
  205  => 'Reset Content',
  206  => 'Partial Content',
  300  => 'Multiple Choices',
  301  => 'Moved Permanently',
  302  => 'Found',
  303  => 'See Other',
  304  => 'Not Modified',
  305  => 'Use Proxy',
  307  => 'Temporary Redirect',
  400  => 'Bad Request',
  401  => 'Unauthorized',
  402  => 'Payment Required',
  403  => 'Forbidden',
  404  => 'Not Found',
  405  => 'Method Not Allowed',
  406  => 'Not Acceptable',
  407  => 'Proxy Authentication Required',
  408  => 'Request Timeout',
  409  => 'Conflict',
  410  => 'Gone',
  411  => 'Length Required',
  412  => 'Precondition Failed',
  413  => 'Request Entity Too Large',
  414  => 'Request-URI Too Large',
  415  => 'Unsupported Media Type',
  416  => 'Requested Range Not Satisfiable',
  417  => 'Expectation Failed',
  500  => 'Internal Server Error',
  501  => 'Not Implemented',
  502  => 'Bad Gateway',
  503  => 'Service Unavailable',
  504  => 'Gateway Timeout',
  505  => 'HTTP Version Not Supported'
}
STATUS_WITH_NO_ENTITY_BODY =

Responses with HTTP status codes that should not have an entity body

Set.new((100..199).to_a << 204 << 304)

Class Method Summary collapse

Class Method Details

.build_query(params) ⇒ Object 



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 54

def build_query(params)
  params.map { |k, v|
    if v.class == Array
      build_query(v.map { |x| [k, x] })
    else
      escape(k) + "=" + escape(v)
    end
  }.join("&")
end

.escape(s) ⇒ Object

Performs URI escaping so that you can construct proper query strings faster. Use this rather than the cgi.rb version since it’s faster. (Stolen from Camping).



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 12

def escape(s)
  s.to_s.gsub(/([^ a-zA-Z0-9_.-]+)/n) {
    '%'+$1.unpack('H2'*$1.size).join('%').upcase
  }.tr(' ', '+')
end

.escape_html(string) ⇒ Object

Escape ampersands, brackets and quotes to their HTML/XML entities.



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 66

def escape_html(string)
  string.to_s.gsub("&", "&amp;").
    gsub("<", "&lt;").
    gsub(">", "&gt;").
    gsub("'", "&#39;").
    gsub('"', "&quot;")
end

.parse_query(qs, d = '&;') ⇒ Object

Stolen from Mongrel, with some small modifications: Parses a query string by breaking it up at the ‘&’ and ‘;’ characters. You can also use this to parse cookies by changing the characters used in the second parameter (which defaults to ‘&;’).



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 33

def parse_query(qs, d = '&;')
  params = {}

  (qs || '').split(/[#{d}] */n).each do |p|
    k, v = unescape(p).split('=', 2)

    if cur = params[k]
      if cur.class == Array
        params[k] << v
      else
        params[k] = [cur, v]
      end
    else
      params[k] = v
    end
  end

  return params
end

.select_best_encoding(available_encodings, accept_encoding) ⇒ Object 



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 75

def select_best_encoding(available_encodings, accept_encoding)
  # http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html

  expanded_accept_encoding =
    accept_encoding.map { |m, q|
      if m == "*"
        (available_encodings - accept_encoding.map { |m2, _| m2 }).map { |m2| [m2, q] }
      else
        [[m, q]]
      end
    }.inject([]) { |mem, list|
      mem + list
    }

  encoding_candidates = expanded_accept_encoding.sort_by { |_, q| -q }.map { |m, _| m }

  unless encoding_candidates.include?("identity")
    encoding_candidates.push("identity")
  end

  expanded_accept_encoding.find_all { |m, q|
    q == 0.0
  }.each { |m, _|
    encoding_candidates.delete(m)
  }

  return (encoding_candidates & available_encodings)[0]
end

.unescape(s) ⇒ Object

Unescapes a URI escaped string. (Stolen from Camping).



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# File 'lib/gems/rack-0.9.1/lib/rack/utils.rb', line 20

def unescape(s)
  s.tr('+', ' ').gsub(/((?:%[0-9a-fA-F]{2})+)/n){
    [$1.delete('%')].pack('H*')
  }
end