1 | /* |
2 | * |
3 | * Copyright 2017 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 | #ifndef GRPC_LOAD_REPORTING_H |
20 | #define GRPC_LOAD_REPORTING_H |
21 | |
22 | #include <grpc/impl/codegen/port_platform.h> |
23 | |
24 | #ifdef __cplusplus |
25 | extern "C" { |
26 | #endif |
27 | |
28 | /** Metadata key for the gRPC LB load balancer token. |
29 | * |
30 | * The value corresponding to this key is an opaque token that is given to the |
31 | * frontend as part of each pick; the frontend sends this token to the backend |
32 | * in each request it sends when using that pick. The token is used by the |
33 | * backend to verify the request and to allow the backend to report load to the |
34 | * gRPC LB system. */ |
35 | #define GRPC_LB_TOKEN_MD_KEY "lb-token" |
36 | |
37 | /** Metadata key for gRPC LB cost reporting. |
38 | * |
39 | * The value corresponding to this key is an opaque binary blob reported by the |
40 | * backend as part of its trailing metadata containing cost information for the |
41 | * call. */ |
42 | #define GRPC_LB_COST_MD_KEY "lb-cost-bin" |
43 | |
44 | #ifdef __cplusplus |
45 | } |
46 | #endif |
47 | |
48 | #endif /* GRPC_LOAD_REPORTING_H */ |
49 | |