WebSocket 1002 Protocol Error vs 1006 Abnormal Closure
Both WebSocket 1002 (Protocol Error) and 1006 (Abnormal Closure) belong to the WebSocket Close Codes category. 1002 indicates that an endpoint is terminating the connection because it received data that violates the WebSocket protocol specification. Meanwhile, 1006 means that a reserved value indicating the connection was closed abnormally without a Close frame being sent. This code must not be set by an endpoint.
Descrição
An endpoint is terminating the connection because it received data that violates the WebSocket protocol specification.
Quando você o vê
The WebSocket frame format is invalid — a malformed header, incorrect masking, or a reserved opcode was used. This usually indicates a broken client or proxy.
Como corrigir
Check that both client and server strictly follow RFC 6455 framing rules. Inspect intermediary proxies that may be corrupting WebSocket frames.
Descrição
A reserved value indicating the connection was closed abnormally without a Close frame being sent. This code must not be set by an endpoint.
Quando você o vê
The TCP connection dropped unexpectedly — the server crashed, the network cable was unplugged, or a firewall killed the idle connection. No proper WebSocket Close handshake occurred.
Como corrigir
Implement reconnection with exponential backoff. Use WebSocket ping/pong frames to detect dead connections early. Check for network-level timeouts or aggressive load balancer idle limits.
Diferenças principais
WebSocket 1002: An endpoint is terminating the connection because it received data that violates the WebSocket protocol specification.
WebSocket 1006: A reserved value indicating the connection was closed abnormally without a Close frame being sent. This code must not be set by an endpoint.
You encounter 1002 when the WebSocket frame format is invalid — a malformed header, incorrect masking, or a reserved opcode was used. This usually indicates a broken client or proxy.
You encounter 1006 when the TCP connection dropped unexpectedly — the server crashed, the network cable was unplugged, or a firewall killed the idle connection. No proper WebSocket Close handshake occurred.
Quando usar qual
For 1002 (Protocol Error): Check that both client and server strictly follow RFC 6455 framing rules. Inspect intermediary proxies that may be corrupting WebSocket frames. For 1006 (Abnormal Closure): Implement reconnection with exponential backoff. Use WebSocket ping/pong frames to detect dead connections early. Check for network-level timeouts or aggressive load balancer idle limits.