Better handling of HEAD requests.

Author: samuel-williams-shopify

lib/protocol/rack/body.rb

@@ -37,8 +37,9 @@ def self.no_content?(status)
 			# @parameter headers [Hash] The response headers.
 			# @parameter body [Object] The response body to wrap.
 			# @parameter input [Object] Optional input for streaming bodies.
+			# @parameter head [Boolean] Indicates if this is a HEAD request, which should not have a body.
 			# @returns [Protocol::HTTP::Body] The wrapped response body.
-			def self.wrap(env, status, headers, body, input = nil)
+			def self.wrap(env, status, headers, body, input = nil, head = false)
 				# In no circumstance do we want this header propagating out:
 				if length = headers.delete(CONTENT_LENGTH)
 					# We don't really trust the user to provide the right length to the transport.
@@ -84,6 +85,14 @@ def self.wrap(env, status, headers, body, input = nil)
 					end
 				end
 
+				if head
+					if body
+						body = ::Protocol::HTTP::Body::Head.for(body)
+					elsif length
+						body = ::Protocol::HTTP::Body::Head.new(length)
+					end
+				end
+				
 				return body
 			end
 

lib/protocol/rack/response.rb

@@ -50,12 +50,7 @@ def self.wrap(env, status, headers, meta, body, request = nil)
 					body = hijack_body
 				end
 
-				body = Body.wrap(env, status, headers, body, request&.body)
-
-				if request&.head?
-					# I thought about doing this in Output.wrap, but decided the semantics are too tricky. Specifically, the various ways a rack response body can be wrapped, and the need to invoke #close at the right point.
-					body = ::Protocol::HTTP::Body::Head.for(body)
-				end
+				body = Body.wrap(env, status, headers, body, request&.body, request&.head?)
 
 				protocol = meta[RACK_PROTOCOL]