WS gateway: Simple, fast and reliable horizontal scaling of websockets.

Introduction

WS Gateway is a simple, fast and reliable solution that allow you to scale websockets server horizontally easily, and painlessly. The plan is to offer different providers for the WS server and pubsub service, but right now the only option is GWS (https://github.com/lxzan/gws) as the WS Server and Redis as pubsub provider.

A common solution to scale websockets is show is this diagram:

However, this library provide an abstraction that allow you to code like if you only had one instance. (See the example below)

Public Interfaces

Server

type FnOnConnect func(connectionId _connection_id.ConnectionId, params map[string]string)
type FnOnDisconnect func(connectionId _connection_id.ConnectionId)
type FnOnPing func(connectionId _connection_id.ConnectionId)
type FnOnMessage func(connectionId _connection_id.ConnectionId, data []byte)

type Server interface {
	Run(port int)
	OnConnect(FnOnConnect)
	OnDisconnect(FnOnDisconnect)
	OnPing(FnOnPing)
	OnMessage(FnOnMessage)
}

Gateway

type Gateway interface {
	Send(id _connection_id.ConnectionId, data []byte)
	Broadcast(group string, data []byte)
	SetGroup(id _connection_id.ConnectionId, group string)
	RemoveGroup(id _connection_id.ConnectionId, group string)
}

Example

An example app can be found here https://github.com/dacalin/demo_chat

	WSConfig := ws_gateway.Config{
		Driver:         ws_gateway.DRIVER_WS_GWS,
		EnableDebugLog: true,
		GWSDriver: ws_gateway.GWSDriverConfig{
			PubSub: 	ws_gateway.PubSubDriverConfig{
				Driver: 		ws_gateway.DRIVER_PUBSUB_REDIS,
				Host:           config.RedisHost,
				Port:           config.RedisPort,
			},
			PingIntervalSeconds: config.WsPingIntervalSeconds,
			WSRoute:             "connect",
		},
	}

	wsServer, wsGatewayConnectio1, err := ws_gateway.Create(WSConfig, ctx)
	if err != nil {
		panic(err)
	}

	wsServer.OnConnect(func(connectionId _connection_id.ConnectionId, params map[string]string) {
		wsGatewayConnection.SetGroup(connectionId, "demo-room")
	})

  // On a message, broadcast the message to all clients. This will automatically
  // sync with different instances through the pubsub service.
	wsServer.OnMessage(
		func(connectionId _connection_id.ConnectionId, data []byte) {
			wsGatewayConnection.Broadcast("demo-room", data)
		})


 // Run the server
	wsServer.Run(config.WsPort)

Roadmap

The lib was designed thinking in future support of different services. The next adapters to be implemented are:

• AWS API Gateway
• RabbitMQ
• Kafka