› Protocol::HTTP › Source › Protocol › HTTP › Header › Digest

class Digest

The digest header provides a digest of the message body for integrity verification.

This header allows servers to send cryptographic hashes of the response body, enabling clients to verify data integrity. Multiple digest algorithms can be specified, and the header is particularly useful as a trailer since the digest can only be computed after the entire message body is available.

Examples

digest = Digest.new("sha-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=")
digest << "md5=9bb58f26192e4ba00f01e2e7b136bbd8"
puts digest.to_s
# => "sha-256=X48E9qOokqqrvdts8nOJRJN3OWDUoyWxBf7kbu9DBPE=, md5=9bb58f26192e4ba00f01e2e7b136bbd8"

Definitions

ENTRY = /\A(?<algorithm>[a-zA-Z0-9][a-zA-Z0-9\-]*)\s*=\s*(?<value>.*)\z/

https://tools.ietf.org/html/rfc3230#section-4.3.2

Entry

A single digest entry in the Digest header.

Implementation

 
Entry = Struct.new(:algorithm, :value) do
	# Create a new digest entry.
	#
	# @parameter algorithm [String] the digest algorithm (e.g., "sha-256", "md5").
	# @parameter value [String] the base64-encoded or hex-encoded digest value.
	def initialize(algorithm, value)
		super(algorithm.downcase, value)
	end
	
	# Convert the entry to its string representation.
	#
	# @returns [String] the formatted digest string.
	def to_s
		"#{algorithm}=#{value}"
	end
end

def entries

Parse the digest header value into a list of digest entries.

Signature
returns　Array(Entry)

the list of digest entries with their algorithms and values.

Implementation

 
def entries
	self.map do |value|
		if match = value.match(ENTRY)
			Entry.new(match[:algorithm], match[:value])
		else
			raise ParseError.new("Could not parse digest value: #{value.inspect}")
		end
	end
end

def self.trailer?

Whether this header is acceptable in HTTP trailers.

Signature
returns　Boolean

true, as digest headers contain integrity hashes that can only be calculated after the entire message body is available.

Implementation

 
def self.trailer?
	true
end