1 /*
2 *
3 * Copyright 2014 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18 19 // Package codes defines the canonical error codes used by gRPC. It is
20 // consistent across various languages.
21 package codes // import "google.golang.org/grpc/codes"
22 23 import (
24 "fmt"
25 "strconv"
26 )
27 28 // A Code is a status code defined according to the [gRPC documentation].
29 //
30 // Only the codes defined as consts in this package are valid codes. Do not use
31 // other code values. Behavior of other codes is implementation-specific and
32 // interoperability between implementations is not guaranteed.
33 //
34 // [gRPC documentation]: https://github.com/grpc/grpc/blob/master/doc/statuscodes.md
35 type Code uint32
36 37 const (
38 // OK is returned on success.
39 OK Code = 0
40 41 // Canceled indicates the operation was canceled (typically by the caller).
42 //
43 // The gRPC framework will generate this error code when cancellation
44 // is requested.
45 Canceled Code = 1
46 47 // Unknown error. An example of where this error may be returned is
48 // if a Status value received from another address space belongs to
49 // an error-space that is not known in this address space. Also
50 // errors raised by APIs that do not return enough error information
51 // may be converted to this error.
52 //
53 // The gRPC framework will generate this error code in the above two
54 // mentioned cases.
55 Unknown Code = 2
56 57 // InvalidArgument indicates client specified an invalid argument.
58 // Note that this differs from FailedPrecondition. It indicates arguments
59 // that are problematic regardless of the state of the system
60 // (e.g., a malformed file name).
61 //
62 // This error code will not be generated by the gRPC framework.
63 InvalidArgument Code = 3
64 65 // DeadlineExceeded means operation expired before completion.
66 // For operations that change the state of the system, this error may be
67 // returned even if the operation has completed successfully. For
68 // example, a successful response from a server could have been delayed
69 // long enough for the deadline to expire.
70 //
71 // The gRPC framework will generate this error code when the deadline is
72 // exceeded.
73 DeadlineExceeded Code = 4
74 75 // NotFound means some requested entity (e.g., file or directory) was
76 // not found.
77 //
78 // This error code will not be generated by the gRPC framework.
79 NotFound Code = 5
80 81 // AlreadyExists means an attempt to create an entity failed because one
82 // already exists.
83 //
84 // This error code will not be generated by the gRPC framework.
85 AlreadyExists Code = 6
86 87 // PermissionDenied indicates the caller does not have permission to
88 // execute the specified operation. It must not be used for rejections
89 // caused by exhausting some resource (use ResourceExhausted
90 // instead for those errors). It must not be
91 // used if the caller cannot be identified (use Unauthenticated
92 // instead for those errors).
93 //
94 // This error code will not be generated by the gRPC core framework,
95 // but expect authentication middleware to use it.
96 PermissionDenied Code = 7
97 98 // ResourceExhausted indicates some resource has been exhausted, perhaps
99 // a per-user quota, or perhaps the entire file system is out of space.
100 //
101 // This error code will be generated by the gRPC framework in
102 // out-of-memory and server overload situations, or when a message is
103 // larger than the configured maximum size.
104 ResourceExhausted Code = 8
105 106 // FailedPrecondition indicates operation was rejected because the
107 // system is not in a state required for the operation's execution.
108 // For example, directory to be deleted may be non-empty, an rmdir
109 // operation is applied to a non-directory, etc.
110 //
111 // A litmus test that may help a service implementor in deciding
112 // between FailedPrecondition, Aborted, and Unavailable:
113 // (a) Use Unavailable if the client can retry just the failing call.
114 // (b) Use Aborted if the client should retry at a higher-level
115 // (e.g., restarting a read-modify-write sequence).
116 // (c) Use FailedPrecondition if the client should not retry until
117 // the system state has been explicitly fixed. E.g., if an "rmdir"
118 // fails because the directory is non-empty, FailedPrecondition
119 // should be returned since the client should not retry unless
120 // they have first fixed up the directory by deleting files from it.
121 // (d) Use FailedPrecondition if the client performs conditional
122 // REST Get/Update/Delete on a resource and the resource on the
123 // server does not match the condition. E.g., conflicting
124 // read-modify-write on the same resource.
125 //
126 // This error code will not be generated by the gRPC framework.
127 FailedPrecondition Code = 9
128 129 // Aborted indicates the operation was aborted, typically due to a
130 // concurrency issue like sequencer check failures, transaction aborts,
131 // etc.
132 //
133 // See litmus test above for deciding between FailedPrecondition,
134 // Aborted, and Unavailable.
135 //
136 // This error code will not be generated by the gRPC framework.
137 Aborted Code = 10
138 139 // OutOfRange means operation was attempted past the valid range.
140 // E.g., seeking or reading past end of file.
141 //
142 // Unlike InvalidArgument, this error indicates a problem that may
143 // be fixed if the system state changes. For example, a 32-bit file
144 // system will generate InvalidArgument if asked to read at an
145 // offset that is not in the range [0,2^32-1], but it will generate
146 // OutOfRange if asked to read from an offset past the current
147 // file size.
148 //
149 // There is a fair bit of overlap between FailedPrecondition and
150 // OutOfRange. We recommend using OutOfRange (the more specific
151 // error) when it applies so that callers who are iterating through
152 // a space can easily look for an OutOfRange error to detect when
153 // they are done.
154 //
155 // This error code will not be generated by the gRPC framework.
156 OutOfRange Code = 11
157 158 // Unimplemented indicates operation is not implemented or not
159 // supported/enabled in this service.
160 //
161 // This error code will be generated by the gRPC framework. Most
162 // commonly, you will see this error code when a method implementation
163 // is missing on the server. It can also be generated for unknown
164 // compression algorithms or a disagreement as to whether an RPC should
165 // be streaming.
166 Unimplemented Code = 12
167 168 // Internal errors. Means some invariants expected by underlying
169 // system has been broken. If you see one of these errors,
170 // something is very broken.
171 //
172 // This error code will be generated by the gRPC framework in several
173 // internal error conditions.
174 Internal Code = 13
175 176 // Unavailable indicates the service is currently unavailable.
177 // This is a most likely a transient condition and may be corrected
178 // by retrying with a backoff. Note that it is not always safe to retry
179 // non-idempotent operations.
180 //
181 // See litmus test above for deciding between FailedPrecondition,
182 // Aborted, and Unavailable.
183 //
184 // This error code will be generated by the gRPC framework during
185 // abrupt shutdown of a server process or network connection.
186 Unavailable Code = 14
187 188 // DataLoss indicates unrecoverable data loss or corruption.
189 //
190 // This error code will not be generated by the gRPC framework.
191 DataLoss Code = 15
192 193 // Unauthenticated indicates the request does not have valid
194 // authentication credentials for the operation.
195 //
196 // The gRPC framework will generate this error code when the
197 // authentication metadata is invalid or a Credentials callback fails,
198 // but also expect authentication middleware to generate it.
199 Unauthenticated Code = 16
200 201 _maxCode = 17
202 )
203 204 var strToCode = map[string]Code{
205 `"OK"`: OK,
206 `"CANCELLED"`:/* [sic] */ Canceled,
207 `"UNKNOWN"`: Unknown,
208 `"INVALID_ARGUMENT"`: InvalidArgument,
209 `"DEADLINE_EXCEEDED"`: DeadlineExceeded,
210 `"NOT_FOUND"`: NotFound,
211 `"ALREADY_EXISTS"`: AlreadyExists,
212 `"PERMISSION_DENIED"`: PermissionDenied,
213 `"RESOURCE_EXHAUSTED"`: ResourceExhausted,
214 `"FAILED_PRECONDITION"`: FailedPrecondition,
215 `"ABORTED"`: Aborted,
216 `"OUT_OF_RANGE"`: OutOfRange,
217 `"UNIMPLEMENTED"`: Unimplemented,
218 `"INTERNAL"`: Internal,
219 `"UNAVAILABLE"`: Unavailable,
220 `"DATA_LOSS"`: DataLoss,
221 `"UNAUTHENTICATED"`: Unauthenticated,
222 }
223 224 // UnmarshalJSON unmarshals b into the Code.
225 func (c *Code) UnmarshalJSON(b []byte) error {
226 // From json.Unmarshaler: By convention, to approximate the behavior of
227 // Unmarshal itself, Unmarshalers implement UnmarshalJSON([]byte("null")) as
228 // a no-op.
229 if string(b) == "null" {
230 return nil
231 }
232 if c == nil {
233 return fmt.Errorf("nil receiver passed to UnmarshalJSON")
234 }
235 236 if ci, err := strconv.ParseUint(string(b), 10, 32); err == nil {
237 if ci >= _maxCode {
238 return fmt.Errorf("invalid code: %d", ci)
239 }
240 241 *c = Code(ci)
242 return nil
243 }
244 245 if jc, ok := strToCode[string(b)]; ok {
246 *c = jc
247 return nil
248 }
249 return fmt.Errorf("invalid code: %q", string(b))
250 }
251