`class Rack2`

The Rack 2 adapter provides compatibility with Rack 2.x applications. It handles the conversion between Protocol::HTTP and Rack 2 environments.

Definitions

`RACK_VERSION = "rack.version"`

The Rack version constant.

`RACK_MULTITHREAD = "rack.multithread"`

Whether the application is multithreaded.

`RACK_MULTIPROCESS = "rack.multiprocess"`

Whether the application is multiprocess.

`RACK_RUN_ONCE = "rack.run_once"`

Whether the application should run only once.

`def make_environment(request)`

Create a Rack 2 environment hash for the request. Sets up all required Rack 2 environment variables and processes the request.

Signature

parameter　request　Protocol::HTTP::Request: The incoming request.
returns　Hash: The Rack 2 environment hash.

Implementation

def make_environment(request)
	request_path, query_string = request.path.split("?", 2)
	server_name, server_port = (request.authority || "").split(":", 2)
	
	env = {
		RACK_VERSION => [2, 0],
		RACK_MULTITHREAD => false,
		RACK_MULTIPROCESS => true,
		RACK_RUN_ONCE => false,
		
		PROTOCOL_HTTP_REQUEST => request,
		
		RACK_INPUT => Input.new(request.body),
		RACK_ERRORS => $stderr,
		RACK_LOGGER => self.logger,

		# The HTTP request method, such as "GET" or "POST". This cannot ever be an empty string, and so is always required.
		CGI::REQUEST_METHOD => request.method,
		
		# The initial portion of the request URL's "path" that corresponds to the application object, so that the application knows its virtual "location". This may be an empty string, if the application corresponds to the "root" of the server.
		CGI::SCRIPT_NAME => "",
		
		# The remainder of the request URL's "path", designating the virtual "location" of the request's target within the application. This may be an empty string, if the request URL targets the application root and does not have a trailing slash. This value may be percent-encoded when originating from a URL.
		CGI::PATH_INFO => request_path,
		CGI::REQUEST_PATH => request_path,
		CGI::REQUEST_URI => request.path,

		# The portion of the request URL that follows the ?, if any. May be empty, but is always required!
		CGI::QUERY_STRING => query_string || "",
		
		# The server protocol (e.g. HTTP/1.1):
		CGI::SERVER_PROTOCOL => request.version,
		
		# The request scheme:
		RACK_URL_SCHEME => request.scheme,
		
		# I'm not sure what sane defaults should be here:
		CGI::SERVER_NAME => server_name,
	}

	# SERVER_PORT is optional but must not be set if it is not present.
	if server_port
		env[CGI::SERVER_PORT] = server_port
	end
	
	self.unwrap_request(request, env)
	
	return env
end

`def call(request)`

Build a rack env from the incoming request and apply it to the rack middleware.

Signature

parameter　request　Protocol::HTTP::Request: The incoming request.
returns　Protocol::HTTP::Response: The HTTP response.
raises　ArgumentError: If the status is not an integer or headers are nil.

Implementation

def call(request)
	env = self.make_environment(request)
	
	status, headers, body = @app.call(env)
	
	if status
		status = status.to_i
	else
		raise ArgumentError, "Status must be an integer!"
	end
	
	unless headers
		raise ArgumentError, "Headers must not be nil!"
	end
	
	# unless body.respond_to?(:each)
	# 	raise ArgumentError, "Body must respond to #each!"
	# end
	
	headers, meta = self.wrap_headers(headers)
	
	# Rack 2 spec does not allow only partial hijacking.
	# if hijack_body = meta[RACK_HIJACK]
	# 	body = hijack_body
	# end
	
	return Response.wrap(env, status, headers, meta, body, request)
rescue => exception
	Console.error(self, exception)
	
	body&.close if body.respond_to?(:close)
	
	return failure_response(exception)
end

`def wrap_headers(fields)`

Process the rack response headers into a Protocol::HTTP::Headers instance, along with any extra rack. metadata. Headers with newline-separated values are split into multiple headers.

Signature

parameter　fields　Hash: The raw response headers.
returns　Tuple(Protocol::HTTP::Headers, Hash): The processed headers and metadata.

Implementation

def wrap_headers(fields)
	headers = ::Protocol::HTTP::Headers.new
	meta = {}
	
	fields.each do |key, value|
		key = key.downcase
		
		if key.start_with?("rack.")
			meta[key] = value
		elsif value.is_a?(String)
			value.split("\n").each do |value|
				headers[key] = value
			end
		else
			headers[key] = value
		end
	end
	
	return headers, meta
end

`def self.make_response(env, response)`

Convert a Protocol::HTTP::Response into a Rack 2 response tuple. Handles protocol upgrades and streaming responses.

Signature

parameter　env　Hash: The rack environment.
parameter　response　Protocol::HTTP::Response: The HTTP response.
returns　Tuple(Integer, Hash, Object): The Rack 2 response tuple [status, headers, body].

Implementation

def self.make_response(env, response)
	# These interfaces should be largely compatible:
	headers = response.headers.to_h
	
	self.extract_protocol(env, response, headers)
	
	if body = response.body and body.stream?
		if env[RACK_IS_HIJACK]
			headers[RACK_HIJACK] = body
			body = []
		end
	end
	
	headers.transform_values! do |value|
		if value.is_a?(Array)
			value.join("\n")
		else
			value
		end
	end
	
	[response.status, headers, body]
end