The Ultimate Guide to Understanding WebSocket Handshake Error

If you’re a developer who has worked with WebSocket, you’re probably aware of the WebSocket handshake error. This error can be frustrating and can cause a lot of headache for developers, especially if they’re new to WebSocket. In this article, we’ll discuss everything you need to know about WebSocket handshake error, what causes it, and how to fix it.

Table of Contents show

What is WebSocket Handshake Error?

WebSocket is a protocol that allows real-time communication between a client and a server. When a client and server establish a WebSocket connection, they exchange a handshake message to confirm that they are compatible and ready to communicate. The WebSocket handshake error occurs when the handshake message fails.

What Causes WebSocket Handshake Error?

WebSocket handshake error can be caused by a number of factors. Some of the most common causes include:

Incorrect URL: If the URL is incorrect, the WebSocket handshake cannot be established. Make sure that the URL is correct and that it includes the correct protocol.
Cross-Origin Resource Sharing (CORS) Error: If the server and client are on different domains, the server may not allow the connection due to CORS. You can fix this by configuring the server to allow connections from the client’s domain.
Firewall or Proxy Error: If there is a firewall or proxy between the client and server, it may block the WebSocket handshake. You may need to configure the firewall or proxy to allow WebSocket connections.
SSL Certificate Error: If the server is using SSL, it may require a valid SSL certificate. If the certificate is invalid or expired, the WebSocket handshake will fail.
Server Configuration Error: If the server is not configured properly, the WebSocket handshake may fail. Check the server’s configuration to ensure that it is set up correctly.

How to Fix WebSocket Handshake Error?

Fixing WebSocket handshake error depends on the cause of the error. Here are some of the common solutions:

Check the URL

The first thing you should do is to check the URL. Make sure that the URL is correct and that it includes the correct protocol. If the URL is incorrect, the WebSocket handshake cannot be established.

Resolve CORS Error

If the server and client are on different domains, you may need to configure the server to allow connections from the client’s domain. This can be done by adding the appropriate CORS headers to the server’s response.

Configure Firewall or Proxy

If there is a firewall or proxy between the client and server, you may need to configure it to allow WebSocket connections. This can be done by allowing connections on the appropriate ports and protocols.

Fix SSL Certificate Error

If the server is using SSL, make sure that the SSL certificate is valid and not expired. If the certificate is invalid or expired, the WebSocket handshake will fail. You may need to update or renew the certificate.

Check Server Configuration

If none of the above solutions work, check the server’s configuration. Make sure that it is set up correctly and that it supports WebSocket connections. You may need to consult the server’s documentation for more information.

FAQ

What is WebSocket?

WebSocket is a protocol that allows real-time communication between a client and a server. It is ideal for applications that require low-latency, bi-directional communication.

What is WebSocket handshake?

WebSocket handshake is the process of establishing a WebSocket connection between a client and a server. During the handshake, the client and server exchange messages to confirm that they are compatible and ready to communicate.

What causes WebSocket handshake error?

WebSocket handshake error can be caused by a number of factors, including incorrect URL, CORS error, firewall or proxy error, SSL certificate error, and server configuration error.

How to fix WebSocket handshake error?

Fixing WebSocket handshake error depends on the cause of the error. Common solutions include checking the URL, resolving CORS error, configuring firewall or proxy, fixing SSL certificate error, and checking server configuration.