A simple example for Bonjour

BonjourClient.swift

//
//  BonjourClient.swift
//  BonjourClient
//
//  Created by Jesse Hao on 2019/5/23.
//  Copyright © 2019 ONES. All rights reserved.
//

import Foundation

class ServiceAgent : NSObject, NetServiceDelegate {
    func netServiceDidResolveAddress(_ sender: NetService) {
        if let data = sender.txtRecordData() {
            let dict = NetService.dictionary(fromTXTRecord: data)
            print("Resolved: \(dict)")
            print(dict.mapValues { String(data: $0, encoding: .utf8) })
        }
    }
}

class BrowserAgent : NSObject, NetServiceBrowserDelegate {
    var currentService:NetService?
    let serviceAgent = ServiceAgent()
    
    func netServiceBrowser(_ browser: NetServiceBrowser, didFindDomain domainString: String, moreComing: Bool) {
        print("domain found: \(domainString)")
    }
    
    func netServiceBrowser(_ browser: NetServiceBrowser, didFind service: NetService, moreComing: Bool) {
        print("service found: \(service.name)")
        self.currentService = service
        service.delegate = self.serviceAgent
        service.resolve(withTimeout: 5)
    }
}

let agent = BrowserAgent()
let browser = NetServiceBrowser()
browser.delegate = agent
browser.searchForServices(ofType: "_dragon._tcp", inDomain: "local.")
browser.schedule(in: RunLoop.main, forMode: .common)
RunLoop.main.run()

BonjourService.swift

//
//  BonjourService.swift
//  BonjourService
//
//  Created by Jesse Hao on 2019/5/23.
//  Copyright © 2019 Snoware. All rights reserved.
//

import Foundation

class ServiceAgent : NSObject, NetServiceDelegate {
    func netServiceDidPublish(_ sender: NetService) {
        print("Bonjour Service published!")
    }
    
    func netService(_ sender: NetService, didNotPublish errorDict: [String : NSNumber]) {
        print("Failed to publish Bonjour Service. error: \(errorDict)")
    }
}

let agent = ServiceAgent()
let runloop = RunLoop.main
let service = NetService(domain: "local.", type: "_dragon._tcp", name: "dragon", port: 2333)
service.schedule(in: runloop, forMode: .common)
service.delegate = agent
let dictData = "Hi".data(using: String.Encoding.utf8)
let data = NetService.data(fromTXTRecord: ["key":dictData!])
print("set data: \(service.setTXTRecord(data))")
service.publish()
runloop.run()

How to use this code? @jessehao