Class: Mime::Type

Inherits:
Object show all
Defined in:
actionpack/lib/action_dispatch/http/mime_type.rb

Overview

Encapsulates the notion of a mime type. Can be used at render time, for example, with:

class PostsController < ActionController::Base
  def show
    @post = Post.find(params[:id])

    respond_to do |format|
      format.html
      format.ics { render :text => post.to_ics, :mime_type => Mime::Type["text/calendar"]  }
      format.xml { render :xml => @people.to_xml }
    end
  end
end

Defined Under Namespace

Classes: AcceptItem

Constant Summary collapse

TRAILING_STAR_REGEXP = 
/(text|application)\/\*/
@@html_types = 
Set.new [:html, :all]
@@browser_generated_types =

These are the content types which browsers can generate without using ajax, flash, etc i.e. following a link, getting an image or posting a form. CSRF protection only needs to protect against these types.

Set.new [:html, :url_encoded_form, :multipart_form, :text]

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(string, symbol = nil, synonyms = []) ⇒ Type

Returns a new instance of Type.



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 205

def initialize(string, symbol = nil, synonyms = [])
  @symbol, @synonyms = symbol, synonyms
  @string = string
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *args) ⇒ Object (private) 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 260

def method_missing(method, *args)
  if method.to_s =~ /(\w+)\?$/
    $1.downcase.to_sym == to_sym
  else
    super
  end
end

Instance Attribute Details

#symbol ⇒ Object (readonly)

Returns the value of attribute symbol



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 54

def symbol
  @symbol
end

Class Method Details

.lookup(string) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 86

def lookup(string)
  LOOKUP[string]
end

.lookup_by_extension(extension) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 90

def lookup_by_extension(extension)
  EXTENSION_LOOKUP[extension.to_s]
end

.parse(accept_header) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 109

def parse(accept_header)
  if accept_header !~ /,/
    if accept_header =~ TRAILING_STAR_REGEXP
      parse_data_with_trailing_star($1)
    else
      [Mime::Type.lookup(accept_header)]
    end
  else
    # keep track of creation order to keep the subsequent sort stable
    list, index = [], 0
    accept_header.split(/,/).each do |header|
      params, q = header.split(/;\s*q=/)
      if params.present?
        params.strip!

        if params =~ TRAILING_STAR_REGEXP
          parse_data_with_trailing_star($1).each do |m|
            list << AcceptItem.new(index, m.to_s, q)
            index += 1
          end
        else
          list << AcceptItem.new(index, params, q)
          index += 1
        end
      end
    end
    list.sort!

    # Take care of the broken text/xml entry by renaming or deleting it
    text_xml = list.index("text/xml")
    app_xml = list.index(Mime::XML.to_s)

    if text_xml && app_xml
      # set the q value to the max of the two
      list[app_xml].q = [list[text_xml].q, list[app_xml].q].max

      # make sure app_xml is ahead of text_xml in the list
      if app_xml > text_xml
        list[app_xml], list[text_xml] = list[text_xml], list[app_xml]
        app_xml, text_xml = text_xml, app_xml
      end

      # delete text_xml from the list
      list.delete_at(text_xml)

    elsif text_xml
      list[text_xml].name = Mime::XML.to_s
    end

    # Look for more specific XML-based types and sort them ahead of app/xml

    if app_xml
      idx = app_xml
      app_xml_type = list[app_xml]

      while(idx < list.length)
        type = list[idx]
        break if type.q < app_xml_type.q
        if type.name =~ /\+xml$/
          list[app_xml], list[idx] = list[idx], list[app_xml]
          app_xml = idx
        end
        idx += 1
      end
    end

    list.map! { |i| Mime::Type.lookup(i.name) }.uniq!
    list
  end
end

.parse_data_with_trailing_star(input) ⇒ Object

input: ‘text’ returned value: [Mime::JSON, Mime::XML, Mime::ICS, Mime::HTML, Mime::CSS, Mime::CSV, Mime::JS, Mime::YAML, Mime::TEXT]

input: ‘application’ returned value: [Mime::HTML, Mime::JS, Mime::XML, Mime::YAML, Mime::ATOM, Mime::JSON, Mime::RSS, Mime::URL_ENCODED_FORM]



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 185

def parse_data_with_trailing_star(input)
  Mime::SET.select { |m| m =~ input }
end

.register(string, symbol, mime_type_synonyms = [], extension_synonyms = [], skip_lookup = false) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 100

def register(string, symbol, mime_type_synonyms = [], extension_synonyms = [], skip_lookup = false)
  Mime.const_set(symbol.to_s.upcase, Type.new(string, symbol, mime_type_synonyms))

  SET << Mime.const_get(symbol.to_s.upcase)

  ([string] + mime_type_synonyms).each { |str| LOOKUP[str] = SET.last } unless skip_lookup
  ([symbol.to_s] + extension_synonyms).each { |ext| EXTENSION_LOOKUP[ext] = SET.last }
end

.register_alias(string, symbol, extension_synonyms = []) ⇒ Object

Registers an alias that’s not used on mime type lookup, but can be referenced directly. Especially useful for rendering different HTML versions depending on the user agent, like an iPhone.



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 96

def register_alias(string, symbol, extension_synonyms = [])
  register(string, symbol, [], extension_synonyms, true)
end

.unregister(symbol) ⇒ Object

This method is opposite of register method.

Usage:

Mime::Type.unregister(:mobile)



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 194

def unregister(symbol)
  symbol = symbol.to_s.upcase
  mime = Mime.const_get(symbol)
  Mime.instance_eval { remove_const(symbol) }

  SET.delete_if { |v| v.eql?(mime) }
  LOOKUP.delete_if { |k,v| v.eql?(mime) }
  EXTENSION_LOOKUP.delete_if { |k,v| v.eql?(mime) }
end

Instance Method Details

#==(mime_type) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 234

def ==(mime_type)
  return false if mime_type.blank?
  (@synonyms + [ self ]).any? do |synonym|
    synonym.to_s == mime_type.to_s || synonym.to_sym == mime_type.to_sym
  end
end

#===(list) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 226

def ===(list)
  if list.is_a?(Array)
    (@synonyms + [ self ]).any? { |synonym| list.include?(synonym) }
  else
    super
  end
end

#=~(mime_type) ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 241

def =~(mime_type)
  return false if mime_type.blank?
  regexp = Regexp.new(Regexp.quote(mime_type.to_s))
  (@synonyms + [ self ]).any? do |synonym|
    synonym.to_s =~ regexp
  end
end

#html? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 255

def html?
  @@html_types.include?(to_sym) || @string =~ /html/
end

#ref ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 222

def ref
  to_sym || to_s
end

#to_s ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 210

def to_s
  @string
end

#to_str ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 214

def to_str
  to_s
end

#to_sym ⇒ Object 



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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 218

def to_sym
  @symbol
end

#verify_request? ⇒ Boolean

Returns true if Action Pack should check requests using this Mime Type for possible request forgery. See ActionController::RequestForgeryProtection.

Returns:

  • (Boolean) 


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# File 'actionpack/lib/action_dispatch/http/mime_type.rb', line 251

def verify_request?
  @@browser_generated_types.include?(to_sym)
end