Function unwrapFlightError

server/conn_errors.go:138–158

unwrapFlightError recovers the underlying error message from an Arrow Flight / gRPC wrapper. gRPC errors stringify as "… rpc error: code = X desc = ", and the control plane further prefixes worker failures with "flight execute update: " (and similar). When the message is not Flight-wrapped

(msg string)

// update: " (and similar). When the message is not Flight-wrapped it is returned
// unchanged, so this is safe to apply unconditionally before prefix matching.
func unwrapFlightError(msg string) string {
	// gRPC puts the real message after the final "desc = ".
	if idx := strings.LastIndex(msg, "desc = "); idx != -1 {
		msg = msg[idx+len("desc = "):]
	}
	msg = strings.TrimSpace(msg)
	// The worker's Flight SQL handler wraps the raw DuckDB error one more time
	// with "failed to execute query: " / "failed to execute update: " (see
	// duckdbservice/flight_handler.go). That sits between "desc = " and the
	// DuckDB exception prefix, so without stripping it the HasPrefix("Catalog
	// Error:" …) classifiers below all miss and the error falls through to
	// XX000. Strip any one such worker prefix so classification sees the bare
	// DuckDB message.
	for _, p := range []string{"failed to execute update: ", "failed to execute query: "} {
		if strings.HasPrefix(msg, p) {
			msg = strings.TrimSpace(msg[len(p):])
			break
		}
	}
	return msg
}

// catalogErrorCode narrows a "Catalog Error: …" message to a specific SQLSTATE
func catalogErrorCode(msg string) string {