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//===----------------------------------------------------------------------===//
//
// This source file is part of the SwiftNIO open source project
//
// Copyright (c) 2017-2018 Apple Inc. and the SwiftNIO project authors
// Licensed under Apache License v2.0
//
// See LICENSE.txt for license information
// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
//
// SPDX-License-Identifier: Apache-2.0
//
//===----------------------------------------------------------------------===//
import NIO
private final class EchoHandler: ChannelInboundHandler {
public typealias InboundIn = ByteBuffer
public typealias OutboundOut = ByteBuffer
public func channelRead(context: ChannelHandlerContext, data: NIOAny) {
// As we are not really interested getting notified on success or failure we just pass nil as promise to
// reduce allocations.
context.write(data, promise: nil)
}
// Flush it out. This can make use of gathering writes if multiple buffers are pending
public func channelReadComplete(context: ChannelHandlerContext) {
context.flush()
}
public func errorCaught(context: ChannelHandlerContext, error: Error) {
print("error: ", error)
// As we are not really interested getting notified on success or failure we just pass nil as promise to
// reduce allocations.
context.close(promise: nil)
}
}
let group = MultiThreadedEventLoopGroup(numberOfThreads: System.coreCount)
let bootstrap = ServerBootstrap(group: group)
// Specify backlog and enable SO_REUSEADDR for the server itself
.serverChannelOption(ChannelOptions.backlog, value: 256)
.serverChannelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1)
// Set the handlers that are appled to the accepted Channels
.childChannelInitializer { channel in
// Ensure we don't read faster than we can write by adding the BackPressureHandler into the pipeline.
channel.pipeline.addHandler(BackPressureHandler()).flatMap { v in
channel.pipeline.addHandler(EchoHandler())
}
}
// Enable SO_REUSEADDR for the accepted Channels
.childChannelOption(ChannelOptions.socketOption(.so_reuseaddr), value: 1)
.childChannelOption(ChannelOptions.maxMessagesPerRead, value: 16)
.childChannelOption(ChannelOptions.recvAllocator, value: AdaptiveRecvByteBufferAllocator())
defer {
try! group.syncShutdownGracefully()
}
// First argument is the program path
let arguments = CommandLine.arguments
let arg1 = arguments.dropFirst().first
let arg2 = arguments.dropFirst(2).first
let defaultHost = "::1"
let defaultPort = 9999
enum BindTo {
case ip(host: String, port: Int)
case unixDomainSocket(path: String)
}
let bindTarget: BindTo
switch (arg1, arg1.flatMap(Int.init), arg2.flatMap(Int.init)) {
case (.some(let h), _ , .some(let p)):
/* we got two arguments, let's interpret that as host and port */
bindTarget = .ip(host: h, port: p)
case (.some(let portString), .none, _):
/* couldn't parse as number, expecting unix domain socket path */
bindTarget = .unixDomainSocket(path: portString)
case (_, .some(let p), _):
/* only one argument --> port */
bindTarget = .ip(host: defaultHost, port: p)
default:
bindTarget = .ip(host: defaultHost, port: defaultPort)
}
let channel = try { () -> Channel in
switch bindTarget {
case .ip(let host, let port):
return try bootstrap.bind(host: host, port: port).wait()
case .unixDomainSocket(let path):
return try bootstrap.bind(unixDomainSocketPath: path).wait()
}
}()
print("Server started and listening on \(channel.localAddress!)")
// This will never unblock as we don't close the ServerChannel
try channel.closeFuture.wait()
print("Server closed")
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