aboutsummaryrefslogtreecommitdiff
path: root/vendor/google.golang.org/grpc/status/status.go
blob: a1348e9b16bd61f83466b94a961d1d7337cf6ce4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
/*
 *
 * 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"
	"errors"
	"fmt"

	"github.com/golang/protobuf/proto"
	"github.com/golang/protobuf/ptypes"
	spb "google.golang.org/genproto/googleapis/rpc/status"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/internal"
)

func init() {
	internal.StatusRawProto = statusRawProto
}

func statusRawProto(s *Status) *spb.Status { return s.s }

// 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) GRPCStatus() *Status {
	return &Status{s: (*spb.Status)(se)}
}

// Is implements future error.Is functionality.
// A statusError is equivalent if the code and message are identical.
func (se *statusError) Is(target error) bool {
	tse, ok := target.(*statusError)
	if !ok {
		return false
	}

	return proto.Equal((*spb.Status)(se), (*spb.Status)(tse))
}

// 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 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
}

// WithDetails returns a new status with the provided details messages appended to the status.
// If any errors are encountered, it returns nil and the first error encountered.
func (s *Status) WithDetails(details ...proto.Message) (*Status, error) {
	if s.Code() == codes.OK {
		return nil, errors.New("no error details for status with code OK")
	}
	// s.Code() != OK implies that s.Proto() != nil.
	p := s.Proto()
	for _, detail := range details {
		any, err := ptypes.MarshalAny(detail)
		if err != nil {
			return nil, err
		}
		p.Details = append(p.Details, any)
	}
	return &Status{s: p}, nil
}

// Details returns a slice of details messages attached to the status.
// If a detail cannot be decoded, the error is returned in place of the detail.
func (s *Status) Details() []interface{} {
	if s == nil || s.s == nil {
		return nil
	}
	details := make([]interface{}, 0, len(s.s.Details))
	for _, any := range s.s.Details {
		detail := &ptypes.DynamicAny{}
		if err := ptypes.UnmarshalAny(any, detail); err != nil {
			details = append(details, err)
			continue
		}
		details = append(details, detail.Message)
	}
	return details
}

// 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())
	}
}