3 * Copyright 2017 gRPC authors.
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
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 #ifndef GRPC_LOAD_REPORTING_H
20 #define GRPC_LOAD_REPORTING_H
22 #include <grpc/impl/codegen/port_platform.h>
28 /** Metadata key for the gRPC LB load balancer token.
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
35 #define GRPC_LB_TOKEN_MD_KEY "lb-token"
37 /** Metadata key for gRPC LB cost reporting.
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
42 #define GRPC_LB_COST_MD_KEY "lb-cost-bin"
48 #endif /* GRPC_LOAD_REPORTING_H */