Class: Webmachine::MediaType

Inherits:
Object
  • Object
show all
Extended by:
Translation
Defined in:
lib/webmachine/media_type.rb

Overview

Encapsulates a MIME media type, with logic for matching types.

Constant Summary collapse

MEDIA_TYPE_REGEX =

Matches valid media types

/^\s*([^;\s]+)\s*((?:;\s*\S+\s*)*)\s*$/.freeze
PARAMS_REGEX =

Matches sub-type parameters

/;\s*([^=]+)(=([^;=\s]*))?/.freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Translation

t

Constructor Details

#initialize(type, params = {}) ⇒ MediaType

Returns a new instance of MediaType.

Parameters:

  • type (String) —

    the main media type, e.g. application/json

  • params (Hash) (defaults to: {}) —

    the media type parameters



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# File 'lib/webmachine/media_type.rb', line 46

def initialize(type, params={})
  @type, @params = type, params
end

Instance Attribute Details

#params ⇒ Hash

Returns any type parameters, e.g. charset.

Returns:

  • (Hash) —

    any type parameters, e.g. charset



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# File 'lib/webmachine/media_type.rb', line 42

def params
  @params
end

#type ⇒ String

Returns the MIME media type.

Returns:

  • (String) —

    the MIME media type



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# File 'lib/webmachine/media_type.rb', line 39

def type
  @type
end

Class Method Details

.parse(obj) ⇒ MediaType

Creates a new MediaType by parsing an alternate representation.

Parameters:

  • obj (MediaType, String, Array<String,Hash>) —

    the raw type to be parsed

Returns:

Raises:

  • (ArgumentError) —

    when the type could not be parsed



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# File 'lib/webmachine/media_type.rb', line 20

def self.parse(obj)
  case obj
  when MediaType
    obj
  when MEDIA_TYPE_REGEX
    type, raw_params = $1, $2
    params = Hash[raw_params.scan(PARAMS_REGEX).map { |m| [m[0], m[2].to_s] }]
    new(type, params)
  else
    unless Array === obj && String === obj[0] && Hash === obj[1]
      raise ArgumentError, t('invalid_media_type', :type => obj.inspect)
    end
    type = parse(obj[0])
    type.params.merge!(obj[1])
    type
  end
end

Instance Method Details

#==(other) ⇒ true, false

Returns Are these two types strictly equal?.

Parameters:

  • other —

    the other media type.

Returns:

  • (true, false) —

    Are these two types strictly equal?

See Also:



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# File 'lib/webmachine/media_type.rb', line 59

def ==(other)
  other = self.class.parse(other)
  other.type == type && other.params == params
end

#exact_match?(other) ⇒ true, false

Detects whether this Webmachine::MediaType matches the other Webmachine::MediaType, taking into account wildcards. Sub-type parameters are treated strictly.

Parameters:

  • other (MediaType, String, Array<String,Hash>) —

    the other type

Returns:

  • (true, false) —

    whether it is an acceptable match



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# File 'lib/webmachine/media_type.rb', line 69

def exact_match?(other)
  other = self.class.parse(other)
  type_matches?(other) && other.params == params
end

#major ⇒ String

Returns The major type, e.g. “application”, “text”, “image”.

Returns:

  • (String) —

    The major type, e.g. “application”, “text”, “image”



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# File 'lib/webmachine/media_type.rb', line 101

def major
  type.split(SLASH).first
end

#match?(other) ⇒ true, false

Detects whether the Webmachine::MediaType is an acceptable match for the other Webmachine::MediaType, taking into account wildcards and satisfying all requested parameters, but allowing this type to have extra specificity.

Parameters:

  • other (MediaType, String, Array<String,Hash>) —

    the other type

Returns:

  • (true, false) —

    whether it is an acceptable match



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# File 'lib/webmachine/media_type.rb', line 80

def match?(other)
  other = self.class.parse(other)
  type_matches?(other) && params_match?(other.params)
end

#matches_all? ⇒ Boolean

Detects whether the Webmachine::MediaType represents an open wildcard type, that is, “/” without any #params.

Returns:

  • (Boolean) 


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# File 'lib/webmachine/media_type.rb', line 52

def matches_all?
  @type == MATCHES_ALL && @params.empty?
end

#minor ⇒ String

Returns the minor or sub-type, e.g. “json”, “html”, “jpeg”.

Returns:

  • (String) —

    the minor or sub-type, e.g. “json”, “html”, “jpeg”



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# File 'lib/webmachine/media_type.rb', line 106

def minor
  type.split(SLASH).last
end

#params_match?(other) ⇒ true, false

Detects whether the passed sub-type parameters are all satisfied by this Webmachine::MediaType. The receiver is allowed to have other params than the ones specified, but all specified must be equal.

Parameters:

  • params (Hash) —

    the requested params

Returns:

  • (true, false) —

    whether it is an acceptable match



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# File 'lib/webmachine/media_type.rb', line 90

def params_match?(other)
  other.all? {|k,v| params[k] == v }
end

#to_s ⇒ String

Reconstitutes the type into a String

Returns:

  • (String) —

    the type as a String



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# File 'lib/webmachine/media_type.rb', line 96

def to_s
  [type, *params.map {|k,v| "#{k}=#{v}" }].join(";")
end

#type_matches?(other) ⇒ true, false

Returns whether the main media type is acceptable, ignoring params and taking into account wildcards.

Parameters:

Returns:

  • (true, false) —

    whether the main media type is acceptable, ignoring params and taking into account wildcards



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# File 'lib/webmachine/media_type.rb', line 113

def type_matches?(other)
  other = self.class.parse(other)
  if [Dispatcher::Route::MATCH_ALL_STR, MATCHES_ALL, type].include?(other.type)
    true
  else
    other.major == major && other.minor == Dispatcher::Route::MATCH_ALL_STR
  end
end