The Ultimate Tornado WebSocket Example Guide: Everything You Need to Know

Introduction

WebSocket is a protocol that enables two-way communication between a client and a server over a single TCP connection. Tornado is a Python web framework that supports WebSockets. In this article, we will explore the Tornado WebSocket example and how to use it to build real-time applications.

What is Tornado WebSocket?

Tornado WebSocket is a module that comes with the Tornado web framework. It provides a full-duplex communication channel between the client and the server. Unlike HTTP, which is a request-response protocol, WebSocket allows real-time communication between the client and the server.

How to Install Tornado WebSocket?

The first step to using Tornado WebSocket is to install the Tornado web framework. You can install it using pip, which is the Python package manager. Simply run the following command:

pip install tornado

Creating a Tornado WebSocket Example

Now that we have installed Tornado, let’s create a simple WebSocket example. In this example, we will create a simple chat application that allows users to send and receive messages in real-time.

Step 1: Import Tornado WebSocket

The first step is to import the WebSocket module from the Tornado web framework. You can do this using the following code:

import tornado.websocket

Step 2: Create a WebSocket Handler

Next, we need to create a WebSocket handler that will handle the WebSocket connection. You can do this using the following code:

class ChatWebSocket(tornado.websocket.WebSocketHandler):

 def open(self):

  print(“WebSocket opened”)

 def on_message(self, message):

  self.write_message(u”You said: ” + message)

 def on_close(self):

  print(“WebSocket closed”)

The above code defines a WebSocket handler that has three methods:

1. open(): This method is called when a new WebSocket connection is established.
2. on_message(): This method is called when a message is received from the client.
3. on_close(): This method is called when the WebSocket connection is closed.

Step 3: Create a Tornado Application

Now, we need to create a Tornado application that will handle HTTP requests and WebSocket connections. You can do this using the following code:

class Application(tornado.web.Application):

 def __init__(self):

  handlers = [(r”/chat”, ChatWebSocket)]

  tornado.web.Application.__init__(self, handlers)

The above code defines a Tornado application that has one handler: the ChatWebSocket handler that we defined earlier. The handler is mapped to the “/chat” URL.

Step 4: Start the Tornado Server

Finally, we need to start the Tornado server. You can do this using the following code:

if __name__ == “__main__”:

 app = Application()

 app.listen(8888)

 tornado.ioloop.IOLoop.current().start()

The above code creates an instance of the Tornado application and starts the server on port 8888.

Running the Tornado WebSocket Example

Now that we have created the WebSocket example, let’s run it and see how it works.

Step 1: Start the Tornado Server

The first step is to start the Tornado server. You can do this by running the following command:

python chat.py

This will start the Tornado server on port 8888.

Step 2: Open the Chat Application

Next, open your web browser and navigate to the following URL:

http://localhost:8888/chat

This will open the chat application in your web browser.

Step 3: Send Messages

You can now send messages in the chat application. Enter a message in the text box and press the “Send” button. The message will be sent to the server using the WebSocket connection, and the server will send the message back to all connected clients.

Conclusion

In this article, we explored the Tornado WebSocket example and how to use it to build real-time applications. We learned how to create a simple chat application that allows users to send and receive messages in real-time. With Tornado WebSocket, you can build real-time applications that are fast, efficient, and reliable.

FAQ

Q: Can Tornado WebSocket be used for large-scale applications?

A: Yes, Tornado WebSocket can be used for large-scale applications. It is fast, efficient, and reliable, making it an ideal choice for real-time applications that require high-performance and scalability.

Q: Is Tornado WebSocket compatible with all web browsers?

A: Yes, Tornado WebSocket is compatible with all modern web browsers that support HTML5. This includes Google Chrome, Mozilla Firefox, Apple Safari, Microsoft Edge, and others.

Q: Can Tornado WebSocket be used for mobile applications?

A: Yes, Tornado WebSocket can be used for mobile applications. It is compatible with both iOS and Android, making it an ideal choice for real-time mobile applications.