| /* |
| * 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 rpc |
| |
| import ( |
| "crypto/tls" |
| "errors" |
| |
| "google.golang.org/grpc" |
| "google.golang.org/grpc/credentials" |
| "google.golang.org/grpc/resolver" |
| "google.golang.org/grpc/resolver/manual" |
| ) |
| |
| var ( |
| ErrAddrEmpty = errors.New("addr is empty") |
| ) |
| |
| type Config struct { |
| Addrs []string |
| Scheme string |
| ServiceName string |
| TLSConfig *TLSConfig |
| } |
| |
| type TLSConfig struct { |
| InsecureSkipVerify bool |
| } |
| |
| func GetPickFirstLbConn(config *Config) (*grpc.ClientConn, error) { |
| return getLbConn(config, func() []grpc.DialOption { |
| return []grpc.DialOption{} |
| }) |
| } |
| |
| func GetRoundRobinLbConn(config *Config) (*grpc.ClientConn, error) { |
| return getLbConn(config, func() []grpc.DialOption { |
| return []grpc.DialOption{ |
| grpc.WithDefaultServiceConfig(`{"loadBalancingConfig": [{"round_robin":{}}]}`), |
| } |
| }) |
| } |
| |
| func getLbConn(config *Config, dialOptions func() []grpc.DialOption) (*grpc.ClientConn, error) { |
| addresses := config.Addrs |
| if len(addresses) <= 0 { |
| return nil, ErrAddrEmpty |
| } |
| |
| addr := make([]resolver.Address, 0, len(addresses)) |
| for _, a := range addresses { |
| addr = append(addr, resolver.Address{Addr: a}) |
| } |
| |
| r := manual.NewBuilderWithScheme(config.Scheme) |
| r.InitialState(resolver.State{Addresses: addr}) |
| |
| opinions := dialOptions() |
| if config.TLSConfig != nil { |
| cfg := &tls.Config{ |
| InsecureSkipVerify: config.TLSConfig.InsecureSkipVerify, |
| } |
| |
| opinions = append(opinions, grpc.WithTransportCredentials(credentials.NewTLS(cfg))) |
| } else { |
| opinions = append(opinions, grpc.WithInsecure()) |
| } |
| |
| opinions = append(opinions, grpc.WithResolvers(r)) |
| |
| conn, err := grpc.Dial(r.Scheme()+":///"+config.ServiceName, opinions...) |
| return conn, err |
| } |