khenaidoo | 5fc5cea | 2021-08-11 17:39:16 -0400 | [diff] [blame] | 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 state declares grpclb types to be set by resolvers wishing to pass |
| 20 | // information to grpclb via resolver.State Attributes. |
| 21 | package state |
| 22 | |
| 23 | import ( |
| 24 | "google.golang.org/grpc/resolver" |
| 25 | ) |
| 26 | |
| 27 | // keyType is the key to use for storing State in Attributes. |
| 28 | type keyType string |
| 29 | |
| 30 | const key = keyType("grpc.grpclb.state") |
| 31 | |
| 32 | // State contains gRPCLB-relevant data passed from the name resolver. |
| 33 | type State struct { |
| 34 | // BalancerAddresses contains the remote load balancer address(es). If |
| 35 | // set, overrides any resolver-provided addresses with Type of GRPCLB. |
| 36 | BalancerAddresses []resolver.Address |
| 37 | } |
| 38 | |
| 39 | // Set returns a copy of the provided state with attributes containing s. s's |
| 40 | // data should not be mutated after calling Set. |
| 41 | func Set(state resolver.State, s *State) resolver.State { |
| 42 | state.Attributes = state.Attributes.WithValues(key, s) |
| 43 | return state |
| 44 | } |
| 45 | |
| 46 | // Get returns the grpclb State in the resolver.State, or nil if not present. |
| 47 | // The returned data should not be mutated. |
| 48 | func Get(state resolver.State) *State { |
| 49 | s, _ := state.Attributes.Value(key).(*State) |
| 50 | return s |
| 51 | } |