`class Accept`

The accept-content-type header represents a list of content-types that the client can accept.

Definitions

`SEPARATOR`

Regular expression used to split values on commas, with optional surrounding whitespace, taking into account quoted strings.

Implementation

SEPARATOR = /
	(?:            # Start non-capturing group
		"[^"\\]*"    # Match quoted strings (no escaping of quotes within)
		|            # OR
		[^,"]+       # Match non-quoted strings until a comma or quote
	)+
	(?=,|\z)       # Match until a comma or end of string
/x

`MediaRange`

A single entry in the Accept: header, which includes a mime type and associated parameters. A media range can include wild cards, but a media type is a specific type and subtype.

Implementation

MediaRange = Struct.new(:type, :subtype, :parameters) do
	# Create a new media range.
	#
	# @parameter type [String] the type of the media range.
	# @parameter subtype [String] the subtype of the media range.
	# @parameter parameters [Hash] the parameters associated with the media range.
	def initialize(type, subtype = "*", parameters = {})
		super(type, subtype, parameters)
	end
	
	# Compare the media range with another media range or a string, based on the quality factor.
	def <=> other
		other.quality_factor <=> self.quality_factor
	end
	
	private def parameters_string
		return "" if parameters == nil or parameters.empty?
		
		parameters.collect do |key, value|
			";#{key.to_s}=#{QuotedString.quote(value.to_s)}"
		end.join
	end
	
	# The string representation of the media range, including the type, subtype, and any parameters.
	def to_s
		"#{type}/#{subtype}#{parameters_string}"
	end
	
	alias to_str to_s
	
	# The quality factor associated with the media range, which is used to determine the order of preference.
	#
	# @returns [Float] the quality factor, which defaults to 1.0 if not specified.
	def quality_factor
		parameters.fetch("q", 1.0).to_f
	end
end

`def initialize(value = nil)`

Parse the accept header value into a list of content types.

Signature

parameter　value　String: the value of the header.

Implementation

def initialize(value = nil)
	if value
		super(value.scan(SEPARATOR).map(&:strip))
	end
end

`def << (value)`

Adds one or more comma-separated values to the header.

The input string is split into distinct entries and appended to the array.

Signature

parameter　value　String: the value or values to add, separated by commas.

Implementation

def << (value)
	self.concat(value.scan(SEPARATOR).map(&:strip))
end

`def to_s`

Serializes the stored values into a comma-separated string.

Signature

returns　String: the serialized representation of the header values.

Implementation

def to_s
	join(",")
end

`def media_ranges`

Parse the accept header.

Signature

returns　Array(Charset): the list of content types and their associated parameters.

Implementation

def media_ranges
	self.map do |value|
		self.parse_media_range(value)
	end
end