grpc_detection

Detects the gRPC variant from the request content-type header and records it for branch-chain routing and observability.

Configuration Notes

Detection values: grpc (bare application/grpc), grpc+proto, grpc+json, grpc+other (unrecognized sub-protocol).

Writes grpc.kind to filter metadata and kind to the grpc_detection filter results. Split a pipeline on the variant with a branch chain (on_result with filter: grpc_detection, key: kind); the router matches client request headers and reads neither filter results nor metadata, so it cannot route on this filter’s output. To gate a filter on gRPC without a branch chain, use the grpc: request condition, which reads the content-type directly.

A non-gRPC request writes neither, so a branch condition cannot match on the absence of gRPC. Branch on a gRPC value and use the fall-through path for everything else.

Example

filter: grpc_detection