Minimal Falcon + Rack + WebSocket Adapter Demo

minimal_falcon_rack_ws_app.rb

require 'async'
require 'async/http/endpoint'
require 'async/websocket/adapters/rack'

require 'falcon'

websocket_endpoint = Async::HTTP::Endpoint.parse('http://127.0.0.1:3000')

module WebSocketApp
  def self.call(env)
    Async::WebSocket::Adapters::Rack.open(env, protocols: %w[ ws ]) do |connection|
      while (message = connection.read)
        # ...
      end
    end or [ 200, { }, [ "Websocket only." ] ]
  end
end

app = Falcon::Server.middleware(WebSocketApp)

Async do
  server = Falcon::Server.new(app, websocket_endpoint)

  server.run
end