blob: 01e182c306c23ffa921e7374f844d4e47f26abed [file] [log] [blame]
/*
*
* Copyright 2017 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
// Package status implements errors returned by gRPC. These errors are
// serialized and transmitted on the wire between server and client, and allow
// for additional data to be transmitted via the Details field in the status
// proto. gRPC service handlers should return an error created by this
// package, and gRPC clients should expect a corresponding error to be
// returned from the RPC call.
//
// This package upholds the invariants that a non-nil error may not
// contain an OK code, and an OK code must result in a nil error.
package status
import (
"context"
"fmt"
spb "google.golang.org/genproto/googleapis/rpc/status"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/internal/status"
)
// Status references google.golang.org/grpc/internal/status. It represents an
// RPC status code, message, and details. It is immutable and should be
// created with New, Newf, or FromProto.
// https://godoc.org/google.golang.org/grpc/internal/status
type Status = status.Status
// New returns a Status representing c and msg.
func New(c codes.Code, msg string) *Status {
return status.New(c, msg)
}
// Newf returns New(c, fmt.Sprintf(format, a...)).
func Newf(c codes.Code, format string, a ...interface{}) *Status {
return New(c, fmt.Sprintf(format, a...))
}
// Error returns an error representing c and msg. If c is OK, returns nil.
func Error(c codes.Code, msg string) error {
return New(c, msg).Err()
}
// Errorf returns Error(c, fmt.Sprintf(format, a...)).
func Errorf(c codes.Code, format string, a ...interface{}) error {
return Error(c, fmt.Sprintf(format, a...))
}
// ErrorProto returns an error representing s. If s.Code is OK, returns nil.
func ErrorProto(s *spb.Status) error {
return FromProto(s).Err()
}
// FromProto returns a Status representing s.
func FromProto(s *spb.Status) *Status {
return status.FromProto(s)
}
// FromError returns a Status representing err if it was produced from this
// package or has a method `GRPCStatus() *Status`. Otherwise, ok is false and a
// Status is returned with codes.Unknown and the original error message.
func FromError(err error) (s *Status, ok bool) {
if err == nil {
return nil, true
}
if se, ok := err.(interface {
GRPCStatus() *Status
}); ok {
return se.GRPCStatus(), true
}
return New(codes.Unknown, err.Error()), false
}
// Convert is a convenience function which removes the need to handle the
// boolean return value from FromError.
func Convert(err error) *Status {
s, _ := FromError(err)
return s
}
// Code returns the Code of the error if it is a Status error, codes.OK if err
// is nil, or codes.Unknown otherwise.
func Code(err error) codes.Code {
// Don't use FromError to avoid allocation of OK status.
if err == nil {
return codes.OK
}
if se, ok := err.(interface {
GRPCStatus() *Status
}); ok {
return se.GRPCStatus().Code()
}
return codes.Unknown
}
// FromContextError converts a context error into a Status. It returns a
// Status with codes.OK if err is nil, or a Status with codes.Unknown if err is
// non-nil and not a context error.
func FromContextError(err error) *Status {
switch err {
case nil:
return nil
case context.DeadlineExceeded:
return New(codes.DeadlineExceeded, err.Error())
case context.Canceled:
return New(codes.Canceled, err.Error())
default:
return New(codes.Unknown, err.Error())
}
}