| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 util |
| |
| import ( |
| "context" |
| "fmt" |
| ) |
| |
| import ( |
| "github.com/pkg/errors" |
| |
| "google.golang.org/grpc/metadata" |
| ) |
| |
| const clientIDKey = "client-id" |
| |
| // ClientIDFromIncomingCtx returns the ID of the peer. Global has the ID |
| // "global" while zones have the zone name. This is also known as the peer ID. |
| func ClientIDFromIncomingCtx(ctx context.Context) (string, error) { |
| return MetadataFromIncomingCtx(ctx, clientIDKey) |
| } |
| |
| func MetadataFromIncomingCtx(ctx context.Context, key string) (string, error) { |
| md, ok := metadata.FromIncomingContext(ctx) |
| if !ok { |
| return "", errors.New("metadata is not provided") |
| } |
| if len(md[key]) == 0 { |
| return "", errors.New(fmt.Sprintf("%q is not present in metadata", key)) |
| } |
| return md[key][0], nil |
| } |