WebSocket 1008 Policy Violation vs 1009 Message Too Big
Both WebSocket 1008 (Policy Violation) and 1009 (Message Too Big) belong to the WebSocket Close Codes category. 1008 indicates that an endpoint is terminating the connection because it received a message that violates its policy. This is a generic code when none of the other codes (1003, 1009) are suitable. Meanwhile, 1009 means that an endpoint is terminating the connection because it received a message that is too large for it to process.
Description
An endpoint is terminating the connection because it received a message that violates its policy. This is a generic code when none of the other codes (1003, 1009) are suitable.
When You See It
The server rejected a message because it violated an application-level policy — for example, sending messages too rapidly, exceeding rate limits, or failing authentication after the handshake.
How to Fix
Review the server's documented policies and constraints. Check for rate limiting, authentication token expiry, or forbidden message content that triggered the rejection.
Description
An endpoint is terminating the connection because it received a message that is too large for it to process.
When You See It
The message payload exceeded the server's configured maximum frame or message size limit. Common when uploading large files or sending huge JSON payloads over WebSocket.
How to Fix
Reduce the message size by chunking large payloads into smaller frames. Alternatively, increase the server's max message size configuration if the large payload is expected.
Key Differences
WebSocket 1008: An endpoint is terminating the connection because it received a message that violates its policy. This is a generic code when none of the other codes (1003, 1009) are suitable.
WebSocket 1009: An endpoint is terminating the connection because it received a message that is too large for it to process.
You encounter 1008 when the server rejected a message because it violated an application-level policy — for example, sending messages too rapidly, exceeding rate limits, or failing authentication after the handshake.
You encounter 1009 when the message payload exceeded the server's configured maximum frame or message size limit. Common when uploading large files or sending huge JSON payloads over WebSocket.
When to Use Which
For 1008 (Policy Violation): Review the server's documented policies and constraints. Check for rate limiting, authentication token expiry, or forbidden message content that triggered the rejection. For 1009 (Message Too Big): Reduce the message size by chunking large payloads into smaller frames. Alternatively, increase the server's max message size configuration if the large payload is expected.