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protocol-buffersenvoyproxy

How to curl a protobuf type_url?

The Envoy documentation gives a configuration example that specifies a type_url of type.googleapis.com/envoy.extensions.listeners.tls_inspector.v3.TlsInspector for a particular configuration stanza.

According to the protobuf documentation, a HTTP GET against this URL should return a protocol message type or an error.

Running curl https://type.googleapis.com/envoy.extensions.listeners.tls_inspector.v3.TlsInspector returns a 404. Is there a way to curl this URL to see the type? Or is the 404 the error the docs were referring to?

Solution

  • This feature would be interesting, but it seems to be something of a relic, at least for the public version of protobuf.

    src/google/protobuf/any.proto:

      // Note: this functionality is not currently available in the official
  // protobuf release, and it is not used for type URLs beginning with
  // type.googleapis.com.