Getting Started

Installation

Add the gem to your project:

$ bundle add async-websocket

Overview Video

Client Implementation

#!/usr/bin/env ruby

require 'async'
require 'async/io/stream'
require 'async/http/endpoint'
require 'async/websocket/client'

USER = ARGV.pop || "anonymous"
URL = ARGV.pop || "http://localhost:7070"

Async do |task|
	stdin = Async::IO::Stream.new(
		Async::IO::Generic.new($stdin)
	)
	
	endpoint = Async::HTTP::Endpoint.parse(URL)
	
	Async::WebSocket::Client.connect(endpoint) do |connection|
		input_task = task.async do
			while line = stdin.read_until("\n")
				connection.write({user: USER, text: line})
				connection.flush
			end
		end
		
		connection.write({
			user: USER,
			status: "connected",
		})
		
		while message = connection.read
			puts message.inspect
		end
	ensure
		input_task&.stop
	end
end

Force HTTP/1 Connection

This forces the endpoint to connect using HTTP/1.1.

endpoint = Async::HTTP::Endpoint.parse("https://remote-server.com", alpn_protocols: Async::HTTP::Protocol::HTTP11.names)

Async::WebSocket::Client.connect(endpoint) do ...

You may want to use this if the server advertises HTTP/2 but doesn't support HTTP/2 for WebSocket connections.

Server Side with Rack & Falcon

#!/usr/bin/env -S falcon serve --bind http://localhost:7070 --count 1 -c

require 'async/websocket/adapters/rack'
require 'set'

$connections = Set.new

run lambda {|env|
	Async::WebSocket::Adapters::Rack.open(env, protocols: ['ws']) do |connection|
		$connections << connection
		
		while message = connection.read
			$connections.each do |connection|
				connection.write(message)
				connection.flush
			end
		end
	ensure
		$connections.delete(connection)
	end or [200, {}, ["Hello World"]]
}