sockets.md

Sockets

Introduction

Socket structs are the objects that are stored in memory per connection and retain the persistent communication.

Sockets define one public method on_connect which can contain functionality that should run when a user connects, including authentication. This methods should return a Bool. If true the socket will remain open. If false the socket will be closed immediately.

An Amber::WebSockets::ClientSocket instance has both cookies and session getters and are available from within the on_connect method.

Socket structs also map topics to the channels they will connect with.

Example Usage

A socket can be generated by calling amber g socket Chat

struct ChatSocket < Amber::WebSockets::ClientSocket
  channel "chat_room:*", ChatRoomChannel

  def on_connect
    # self.session and self.cookies available here
    # do authentication here like
    # !self.session[:user_id].nil?

    # returning true accept all connections
    true
  end
end

Add a new Route

A new route needs to be added so that a handshake can be established with the server. Notice how after \chat, the struct ChatSocket that was created above is mapped to that route.

Amber::Server.configure do |app|
  pipeline :web do
    # pipelines...
  end

  routes :web do
    # other routes,,,
    websocket "/chat", ChatSocket
  end
end

Send messages from controllers (or anywhere else)

Amber::WebSockets::ClientSocket provides a public class method broadcast for publishing messages to all subscribers of a topic from within controllers or anywhere else in your application.

class HomeController < ApplicationController
  def index
    ChatSocket.broadcast("message", "chat_room:123", "message_new", {"message" => "A new visitor!"})
    render("index.slang")
  end
end