prometheus/vendor/google.golang.org/grpc/status/status.go
2017-07-06 14:38:20 +02:00

146 lines
4.7 KiB
Go

/*
*
* Copyright 2017, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
// 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 (
"fmt"
"github.com/golang/protobuf/proto"
spb "google.golang.org/genproto/googleapis/rpc/status"
"google.golang.org/grpc/codes"
)
// statusError is an alias of a status proto. It implements error and Status,
// and a nil statusError should never be returned by this package.
type statusError spb.Status
func (se *statusError) Error() string {
p := (*spb.Status)(se)
return fmt.Sprintf("rpc error: code = %s desc = %s", codes.Code(p.GetCode()), p.GetMessage())
}
func (se *statusError) status() *Status {
return &Status{s: (*spb.Status)(se)}
}
// Status represents an RPC status code, message, and details. It is immutable
// and should be created with New, Newf, or FromProto.
type Status struct {
s *spb.Status
}
// Code returns the status code contained in s.
func (s *Status) Code() codes.Code {
if s == nil || s.s == nil {
return codes.OK
}
return codes.Code(s.s.Code)
}
// Message returns the message contained in s.
func (s *Status) Message() string {
if s == nil || s.s == nil {
return ""
}
return s.s.Message
}
// Proto returns s's status as an spb.Status proto message.
func (s *Status) Proto() *spb.Status {
if s == nil {
return nil
}
return proto.Clone(s.s).(*spb.Status)
}
// Err returns an immutable error representing s; returns nil if s.Code() is
// OK.
func (s *Status) Err() error {
if s.Code() == codes.OK {
return nil
}
return (*statusError)(s.s)
}
// New returns a Status representing c and msg.
func New(c codes.Code, msg string) *Status {
return &Status{s: &spb.Status{Code: int32(c), Message: 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{s: proto.Clone(s).(*spb.Status)}
}
// FromError returns a Status representing err if it was produced from this
// package, otherwise it returns nil, false.
func FromError(err error) (s *Status, ok bool) {
if err == nil {
return &Status{s: &spb.Status{Code: int32(codes.OK)}}, true
}
if s, ok := err.(*statusError); ok {
return s.status(), true
}
return nil, false
}