`class Middleware`

Rack middleware that intercepts WebSocket upgrade requests and dispatches them to ActionCable, passing all other requests to the next app in the middleware stack.

Definitions

`def initialize(app, path: "/cable", server: ActionCable.server)`

Create a new middleware instance.

Signature

parameter　app　#call: The next Rack application in the middleware stack.
parameter　path　String: The URL path that the cable endpoint is mounted at.
parameter　server　ActionCable::Server::Base: The ActionCable server to use.

Implementation

def initialize(app, path: "/cable", server: ActionCable.server)
	@app = app
	@path = path
	@server = server
	@coder = ActiveSupport::JSON
	@protocols = ::ActionCable::INTERNAL[:protocols]
end

`def valid_path?(env)`

Check whether the request path matches the configured cable path.

Signature

parameter　env　Hash: The Rack environment.
returns　Boolean: Whether the request is for the cable endpoint.

Implementation

def valid_path?(env)
	env["PATH_INFO"] == @path
end

`def call(env)`

Handle an incoming Rack request. WebSocket upgrade requests on the configured path are handed off to ActionCable; all other requests are forwarded to the next app in the middleware stack.

Signature

parameter　env　Hash: The Rack environment.
returns　Array: A Rack response triple.

Implementation

def call(env)
	if valid_path?(env) and Async::WebSocket::Adapters::Rack.websocket?(env) and allow_request_origin?(env)
		Async::WebSocket::Adapters::Rack.open(env, protocols: @protocols) do |websocket|
			handle_incoming_websocket(env, websocket)
		end
	else
		@app.call(env)
	end
end

`def allow_request_origin?(env)`

TODO: Shouldn't this be moved to ActionCable::Server::Base?

Implementation

def allow_request_origin?(env)
	if @server.config.disable_request_forgery_protection
		return true
	end
	
	proto = ::Rack::Request.new(env).ssl? ? "https" : "http"
	
	if @server.config.allow_same_origin_as_host && env["HTTP_ORIGIN"] == "#{proto}://#{env["HTTP_HOST"]}"
		return true
	elsif Array(@server.config.allowed_request_origins).any?{|allowed_origin| allowed_origin === env["HTTP_ORIGIN"]}
		return true
	end
	
	Console.warn(self, "Request origin not allowed!", origin: env["HTTP_ORIGIN"])
	return false
end