1 /* 2 * Copyright 2021 Google Inc. All rights reserved. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 import FlatBuffers 18 import GRPC 19 import Logging 20 import Model 21 import NIO 22 23 class Greeter: models_GreeterProvider { 24 25 var interceptors: models_GreeterServerInterceptorFactoryProtocol? 26 27 let greetings: [String] 28 29 init() { 30 greetings = ["Hi", "Hallo", "Ciao"] 31 } 32 33 func SayHello( 34 request: Message<models_HelloRequest>, 35 context: StatusOnlyCallContext) 36 -> EventLoopFuture<Message<models_HelloReply>> 37 { 38 let recipient = request.object.name ?? "Stranger" 39 40 var builder = FlatBufferBuilder() 41 let off = builder.create(string: "Hello \(recipient)") 42 let root = models_HelloReply.createHelloReply(&builder, messageOffset: off) 43 builder.finish(offset: root) 44 return context.eventLoop 45 .makeSucceededFuture(Message<models_HelloReply>(builder: &builder)) 46 } 47 48 func SayManyHellos( 49 request: Message<models_HelloRequest>, 50 context: StreamingResponseCallContext<Message<models_HelloReply>>) 51 -> EventLoopFuture<GRPCStatus> 52 { 53 for name in greetings { 54 var builder = FlatBufferBuilder() 55 let off = builder 56 .create(string: "\(name) \(request.object.name ?? "Unknown")") 57 let root = models_HelloReply.createHelloReply( 58 &builder, 59 messageOffset: off) 60 builder.finish(offset: root) 61 _ = context.sendResponse(Message<models_HelloReply>(builder: &builder)) 62 } 63 return context.eventLoop.makeSucceededFuture(.ok) 64 } 65 } 66 67 // Quieten the logs. 68 LoggingSystem.bootstrap { 69 var handler = StreamLogHandler.standardOutput(label: $0) 70 handler.logLevel = .critical 71 return handler 72 } 73 74 let group = MultiThreadedEventLoopGroup(numberOfThreads: 1) 75 defer { 76 try! group.syncShutdownGracefully() 77 } 78 79 // Create some configuration for the server: 80 let configuration = Server.Configuration( 81 target: .hostAndPort("localhost", 0), 82 eventLoopGroup: group, 83 serviceProviders: [Greeter()]) 84 85 // Start the server and print its address once it has started. 86 let server = Server.start(configuration: configuration) 87 server.map { 88 $0.channel.localAddress 89 }.whenSuccess { address in 90 print("server started on port \(address!.port!)") 91 } 92 93 // Wait on the server's `onClose` future to stop the program from exiting. 94 _ = try server.flatMap { 95 $0.onClose 96 }.wait() 97