What is WebSocket?<\/h2>\n\n\n\n
A WebSocket<\/strong> allows two-way communication (bidirectional) between two entities over a single TCP connection. This means a WebSocket client and server can interact with each other multiple times in a single connection.<\/p>\n\n\n\n A Websocket connection is a fully-duplex connection protocol which means the data can be sent and received simultaneously in both directions, keeping the connection alive until either server or client decides to stop the connection.<\/p>\n\n\n\n It is used in real-time applications to exchange low-latency data in both directions.<\/p>\n\n\n\n In this section, you will create a WebSocket server and client using Python. You will use Python’s Open your terminal window and run the following command:<\/p>\n\n\n\n Using the In this section, you’ll create a WebSocket server that will retrieve the values from the client and based on those values sends the appropriate response to the client.<\/p>\n\n\n\n The above code imports the The code then defines an asynchronous function called Inside the function, a Within the loop, the code receives two values from the client using the The code then sends the appropriate response back to the client based on the values it gets.<\/p>\n\n\n\n In the The code then defines another asynchronous function called The server will run forever due to In the end, the In this section, you’ll create a client that takes the input from the user and displays the response sent by the WebSocket server.<\/p>\n\n\n\n The above code defines an asynchronous function called The user is prompted to enter the name and if they type “exit”<\/strong>, the code quits the process. Then the user is asked to enter their age and both values ( After that, the code enters the infinite loop to continuously listen to the incoming messages from the server using the Finally, the You need to put the server and client code in two separate Python files. First, you need to run the WebSocket server script to start the server.<\/p>\n\n\n\n Open a terminal window, navigate to the project directory, and run the script file, in this case, the script is stored in the Now open another terminal window and run the WebSocket client script, in this case, the script is stored in the This will start the WebSocket client connected to the server. You will see the prompts asking for your name<\/strong> and age<\/strong>.<\/p>\n\n\n Here, The information entered by the user will be displayed on the WebSocket server console. You can see this in the image below.<\/p>\n\n\n You can also run the client using the websockets interactive shell using the following command.<\/p>\n\n\n\n In this article, you learned to create a WebSocket server and client using the websockets library in Python. This technology is used in applications in which data changes in real-time.<\/p>\n\n\n\n Resource: https:\/\/websockets.readthedocs.io\/en\/stable\/howto\/quickstart.html<\/a><\/p>\n\n\n\n \ud83c\udfc6Other articles you might be interested in if you liked this one<\/strong><\/p>\n\n\n\n \u2705Create multi-threaded Python programs using a threading module<\/a>.<\/p>\n\n\n\n \u2705What is the StandardScaler function in Machine Learning<\/a>?<\/p>\n\n\n\n \u2705Upload and display images on the frontend using Flask<\/a>.<\/p>\n\n\n\n \u2705What is Python coroutines and how to use it to execute tasks asynchronously<\/a>?<\/p>\n\n\n\n \u2705How to use async\/await in Python using the asyncio module<\/a>?<\/p>\n\n\n\nHow to Create a WebSocket using Python<\/h2>\n\n\n\n
websockets<\/code> library to create a server and a client.<\/p>\n\n\n\nInstall Dependency<\/h3>\n\n\n\n
pip install websockets<\/pre><\/div>\n\n\n\n
websockets<\/code> library, you can create a websocket server and client in Python super easily.<\/p>\n\n\n\nCreate a WebSocket Server<\/h3>\n\n\n\n
import websockets\nimport asyncio\n\n# Creating WebSocket server\nasync def ws_server(websocket):\n print(\"WebSocket: Server Started.\")\n\n try:\n while True:\n # Receiving values from client\n name = await websocket.recv()\n age = await websocket.recv()\n\n # Prompt message when any of the field is missing\n if name == \"\" or age == \"\":\n print(\"Error Receiving Value from Client.\")\n break\n\n # Printing details received by client\n print(\"Details Received from Client:\")\n print(f\"Name: {name}\")\n print(f\"Age: {age}\")\n\n # Sending a response back to the client\n if int(age) < 18:\n await websocket.send(f\"Sorry! {name}, You can't join the club.\")\n else:\n await websocket.send(f\"Welcome aboard, {name}.\")\n\n except websockets.ConnectionClosedError:\n print(\"Internal Server Error.\")\n\n\nasync def main():\n async with websockets.serve(ws_server, \"localhost\", 7890):\n await asyncio.Future() # run forever\n\nif __name__ == \"__main__\":\n asyncio.run(main())<\/pre><\/div>\n\n\n\nwebsockets<\/code> library for creating a WebSocket server and communicating with it and the asyncio<\/code><\/a> library for making use of asynchronous tasks.<\/p>\n\n\n\nws_server()<\/code> that takes WebSocket connection (websocket<\/code>) as its parameter.<\/p>\n\n\n\ntry<\/code> block is used that handles the incoming messages from the client. Within the try<\/code> block, a while<\/code> loop is created which means the code will run continuously.<\/p>\n\n\n\nwebsocket.recv()<\/code> and stores them within the name<\/code> and age<\/code> variables respectively. The code checks if any of the value is missing, if it is then it prompts a message and breaks the loops otherwise it proceeds and prints the values received from the client.<\/p>\n\n\n\nexcept<\/code> block, the code handles any websockets.ConnectionClosedError<\/code> exceptions that indicate an error occurred during the connection.<\/p>\n\n\n\nmain()<\/code> that starts a WebSocket server. The WebSocket server is created using websockets.serve()<\/code> method which listens on localhost<\/code> and port 7890<\/code>.<\/p>\n\n\n\nasyncio.Future()<\/code>. This will keep the server alive and run continuously to listen to incoming messages.<\/p>\n\n\n\nmain()<\/code> function is run using the asyncio.run(main())<\/code>.<\/p>\n\n\n\nCreate a WebSocket Client<\/h3>\n\n\n\n
import websockets\nimport asyncio\n\n# The main function that will handle connection and communication\n# with the server\nasync def ws_client():\n print(\"WebSocket: Client Connected.\")\n url = \"ws:\/\/127.0.0.1:7890\"\n # Connect to the server\n async with websockets.connect(url) as ws:\n name = input(\"Your Name (type 'exit' to quit): \")\n\n if name == 'exit':\n exit()\n\n age = input(\"Your Age: \")\n # Send values to the server\n await ws.send(f\"{name}\")\n await ws.send(f\"{age}\")\n\n # Stay alive forever, listen to incoming msgs\n while True:\n msg = await ws.recv()\n print(msg)\n\n# Start the connection\nasyncio.run(ws_client())<\/pre><\/div>\n\n\n\nws_client()<\/code>. Inside the function, the WebSocket client is connected to the WebSocket server using the websockets.connect()<\/code> method passed with the URL (ws:\/\/127.0.0.1:789<\/code>) of the server created in the previous section.<\/p>\n\n\n\nname<\/code> and age<\/code>) are sent to the WebSocket server using the ws.send()<\/code> method.<\/p>\n\n\n\nws.recv()<\/code> method. The message is then printed on the console.<\/p>\n\n\n\nws_client()<\/code> function is run using asyncio.run(ws_client())<\/code>. This will start the WebSocket client to accept the information from the user and display the response sent by the server.<\/p>\n\n\n\nRunning the WebSocket Server and Client<\/h2>\n\n\n\n
main.py<\/code> Python file.<\/p>\n\n\n\npython main.py<\/pre><\/div>\n\n\n\n
client.py<\/code> file.<\/p>\n\n\n\npython client.py<\/pre><\/div>\n\n\n\n
![\"WebSocket](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/10\/image-3.png\")
<\/figure><\/div>\n\n\n\"Sachin\"<\/code> and \"22\"<\/code> are sent to the server, and in return, the server responds with the \"Welcome aboard, Sachin\"<\/code> message on the console.<\/p>\n\n\n\n![\"WebSocket](\"https:\/\/geekpython.in\/wp-content\/uploads\/2023\/10\/image-4.png\")
<\/figure><\/div>\n\n\npython -m websockets ws:\/\/localhost:7890<\/pre><\/div>\n\n\n\n
Conclusion<\/h2>\n\n\n\n
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