gitee.com/ks-custle/core-gm@v0.0.0-20230922171213-b83bdd97b62c/grpc/internal/grpcutil/metadata.go (about) 1 /* 2 * 3 * Copyright 2020 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 grpcutil 20 21 import ( 22 "context" 23 24 "gitee.com/ks-custle/core-gm/grpc/metadata" 25 ) 26 27 type mdExtraKey struct{} 28 29 // WithExtraMetadata creates a new context with incoming md attached. 30 func WithExtraMetadata(ctx context.Context, md metadata.MD) context.Context { 31 return context.WithValue(ctx, mdExtraKey{}, md) 32 } 33 34 // ExtraMetadata returns the incoming metadata in ctx if it exists. The 35 // returned MD should not be modified. Writing to it may cause races. 36 // Modification should be made to copies of the returned MD. 37 func ExtraMetadata(ctx context.Context) (md metadata.MD, ok bool) { 38 md, ok = ctx.Value(mdExtraKey{}).(metadata.MD) 39 return 40 }