NewEchoJSONClient creates a JSON client that implements the Echo interface.

NewEchoProtobufClient creates a Protobuf client that implements the Echo interface.

NewEchoServer builds a TwirpServer that can be used as an http.Handler to handle HTTP requests that are routed to the right method in the provided svc implementation.

WriteError writes an HTTP response with a valid Twirp error format (code, msg, meta).

EchoPathPrefix is a convenience constant that may identify URL paths.

HTTPClient is the interface used by generated clients to send HTTP requests.

TwirpServer is the interface generated server structs will support: they're HTTP handlers with additional methods for accessing metadata about the service.