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

MEDIA_TYPE_REGEX =

Matches valid media types

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

Matches sub-type parameters

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

Instance Attribute Summary (collapse)

Class Method Summary (collapse)

Instance Method Summary (collapse)

Methods included from Translation

t

Constructor Details

- (MediaType) initialize(type, params = {})

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 44

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

Instance Attribute Details

- (Hash) params

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 40

def params
  @params
end

- (String) type

Returns the MIME media type

Returns:

  • (String)

    the MIME media type



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# File 'lib/webmachine/media_type.rb', line 37

def type
  @type
end

Class Method Details

+ (MediaType) parse(obj)

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 18

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

- (true, false) ==(other)

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 57

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

- (true, false) exact_match?(other)

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 67

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

- (String) major

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 99

def major
  type.split("/").first
end

- (true, false) match?(other)

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 78

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

- (Boolean) matches_all?

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 50

def matches_all?
  @type == "*/*" && @params.empty?
end

- (String) minor

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 104

def minor
  type.split("/").last
end

- (true, false) params_match?(other)

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 88

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

- (String) to_s

Reconstitutes the type into a String

Returns:

  • (String)

    the type as a String



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# File 'lib/webmachine/media_type.rb', line 94

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

- (true, false) type_matches?(other)

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 111

def type_matches?(other)
  other = self.class.parse(other)
  if ["*", "*/*", type].include?(other.type)
    true
  else
    other.major == major && other.minor == "*"
  end
end