The Ultimate Guide to Gorilla Websocket Example

Websockets are a popular communication protocol that enables two-way communication between a server and a client. Gorilla Websocket is a Go implementation of the websocket protocol that is easy to use and highly scalable. In this article, we will explore Gorilla Websocket Example and its various use cases.

What is Gorilla Websocket?

Gorilla Websocket is a Go package that provides a high-performance implementation of the websocket protocol. It is built on top of the standard net/http package and provides a simple and easy-to-use API for creating websocket servers and clients.

The package provides various features such as message buffering, message fragmentation, and support for custom protocols. It also supports the latest version of the websocket protocol, which is defined in RFC 6455.

Why use Gorilla Websocket?

Gorilla Websocket is a popular choice for building real-time web applications that require two-way communication between a server and a client. Its performance and scalability make it an ideal choice for building applications that require high concurrency and low latency.

Here are some reasons why you should consider using Gorilla Websocket:

  • Easy to use API
  • High performance
  • Scalable
  • Supports custom protocols
  • Message buffering and fragmentation
  • Supports the latest version of the websocket protocol

Gorilla Websocket Example

Let’s take a look at a simple example of using Gorilla Websocket to build a real-time chat application. We will create a server that listens for incoming websocket connections and broadcasts any messages received to all connected clients.

Step 1: Create a new project

The first step is to create a new Go project. Open your terminal and run the following command:

mkdir my-chat-appcd my-chat-appgo mod init my-chat-app

Step 2: Install Gorilla Websocket

The next step is to install the Gorilla Websocket package. Run the following command to install the package:

go get github.com/gorilla/websocket

Step 3: Create the server

Next, we will create the server that listens for incoming websocket connections. Create a new file called server.go and add the following code:

package main

import ("fmt""log""net/http"

"github.com/gorilla/websocket")

var upgrader = websocket.Upgrader{ReadBufferSize:1024,WriteBufferSize: 1024,}

func main() {http.HandleFunc("/ws", handleConnections)err := http.ListenAndServe(":8080", nil)if err != nil {log.Fatal("Error starting server:", err)}}

func handleConnections(w http.ResponseWriter, r *http.Request) {// Upgrade initial GET request to a websocketws, err := upgrader.Upgrade(w, r, nil)if err != nil {log.Fatal(err)}// Make sure we close the connection when the function returnsdefer ws.Close()

// Register our new clientclients[ws] = true

for {var msg Message// Read in a new message as JSON and map it to a Message objecterr := ws.ReadJSON(&msg)if err != nil {log.Printf("error: %v", err)delete(clients, ws)break}// Send the newly received message to the broadcast channelbroadcast <- msg}}

In the above code, we have defined a function called handleConnections that is responsible for upgrading the initial HTTP request to a websocket connection. We have also defined a broadcast channel that will be used to broadcast any messages received to all connected clients.

Step 4: Create the client

Now that we have created the server, let’s create the client that will connect to the server and send and receive messages. Create a new file called client.go and add the following code:

package main

import ("fmt""log""os""os/signal""syscall"

"github.com/gorilla/websocket")

func main() {interrupt := make(chan os.Signal, 1)signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)

// Connect to the serveru := "ws://localhost:8080/ws"log.Printf("connecting to %s", u)

ws, _, err := websocket.DefaultDialer.Dial(u, nil)if err != nil {log.Fatal("Error connecting to server:", err)}defer ws.Close()

done := make(chan struct{})

// Read messages from the servergo func() {defer close(done)for {_, message, err := ws.ReadMessage()if err != nil {log.Printf("error: %v", err)return}fmt.Printf("Received message: %s\n", message)}}()

// Send messages to the serverfor {select {case <-interrupt:// Interrupt signal receivedlog.Println("Interrupt signal received")err := ws.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))if err != nil {log.Println("Error sending close message:", err)}select {case <-done:case <-time.After(time.Second):}return}}}

In the above code, we have defined a function called main that is responsible for connecting to the server and sending and receiving messages. We have also defined a done channel that will be used to signal when the client has finished executing.

Step 5: Run the application

Now that we have created the server and client, let’s run the application. Open two terminal windows and navigate to the my-chat-app directory in each window. In the first window, run the following command:

go run server.go

In the second window, run the following command:

go run client.go

You should now see the client connect to the server and print out any messages received. You can test the application by typing a message in the client window and pressing enter. The message should be broadcasted to all connected clients.

Gorilla Websocket Use Cases

Gorilla Websocket is a versatile package that can be used in a variety of use cases. Here are some common use cases:

Real-time chat applications

Real-time chat applications require two-way communication between a server and a client. Gorilla Websocket is an ideal choice for building real-time chat applications because of its performance and scalability.

Real-time gaming applications

Real-time gaming applications require low latency and high concurrency. Gorilla Websocket is an ideal choice for building real-time gaming applications because of its performance and scalability.

Real-time monitoring applications

Real-time monitoring applications require real-time updates and low latency. Gorilla Websocket is an ideal choice for building real-time monitoring applications because of its performance and scalability.

FAQ

What is Gorilla Websocket?

Gorilla Websocket is a Go package that provides a high-performance implementation of the websocket protocol.

Why use Gorilla Websocket?

Gorilla Websocket is a popular choice for building real-time web applications that require two-way communication between a server and a client. Its performance and scalability make it an ideal choice for building applications that require high concurrency and low latency.

What are some use cases for Gorilla Websocket?

Gorilla Websocket can be used in a variety of use cases, including real-time chat applications, real-time gaming applications, and real-time monitoring applications.

How do I install Gorilla Websocket?

You can install Gorilla Websocket by running the following command:

go get github.com/gorilla/websocket

Can Gorilla Websocket be used with other programming languages?

No, Gorilla Websocket is a Go package and can only be used with Go.

Is Gorilla Websocket production-ready?

Yes, Gorilla Websocket is production-ready and is used by many companies in production environments.

Can Gorilla Websocket be used with a load balancer?

Yes, Gorilla Websocket can be used with a load balancer. However, you need to configure the load balancer to use sticky sessions to ensure that a client’s connection is always routed to the same server.