Function encodeWrapper

errbase/encode.go:131–182

encodeWrapper encodes an error wrapper.

(ctx context.Context, err, cause error)

// encodeWrapper encodes an error wrapper.
func encodeWrapper(ctx context.Context, err, cause error) EncodedError {
	var msg string
	var details errorspb.EncodedErrorDetails
	messageType := Prefix

	if e, ok := err.(*opaqueWrapper); ok {
		// We delegate all knowledge of the error string
		// to the original encoder and do not try to re-engineer
		// the prefix out of the error. This helps maintain
		// backward compatibility with earlier versions of the
		// encoder which don't have any understanding of
		// error string ownership by the wrapper.
		msg = e.prefix
		details = e.details
		messageType = e.messageType
	} else {
		details.OriginalTypeName, details.ErrorTypeMark.FamilyName, details.ErrorTypeMark.Extension = getTypeDetails(err, false /*onlyFamily*/)

		var payload proto.Message

		// If we have a manually registered encoder, use that.
		typeKey := TypeKey(details.ErrorTypeMark.FamilyName)
		if enc, ok := encoders[typeKey]; ok {
			msg, details.ReportablePayload, payload, messageType = enc(ctx, err)
		} else {
			// No encoder.
			// In that case, we'll try to compute a message prefix
			// manually.
			msg, messageType = extractPrefix(err, cause)

			// If there are known safe details, use them.
			if s, ok := err.(SafeDetailer); ok {
				details.ReportablePayload = s.SafeDetails()
			}

			// That's all we can get.
		}
		// If there is a detail payload, encode it.
		details.FullDetails = encodeAsAny(ctx, err, payload)
	}

	return EncodedError{
		Error: &errorspb.EncodedError_Wrapper{
			Wrapper: &errorspb.EncodedWrapper{
				Cause:       EncodeError(ctx, cause),
				Message:     msg,
				Details:     details,
				MessageType: errorspb.MessageType(messageType),
			},
		},
	}
}

// extractPrefix extracts the prefix from a wrapper's error message.
// For example,