Swift URLSession – Network

URLSession

URLSession is network API provided by Apple.

Simple Usage

In this time cover simple API.

• http://localhost:8000/list (GET : return json list)
• http://localhost:8000/users/1 (GET : return one json object)
• https://localhost:8000/post (POST : any body acceptable)

This is sample codes

import UIKit
import Foundation
import PlaygroundSupport

PlaygroundPage.current.needsIndefiniteExecution = true

class HttpClient: NSObject {
    func getRequest(url urlString: String) {
        guard let url = URL(string: urlString) else {return}
        let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
            self.printData(error: error, response: response)
            guard let data = data else { return }
            print(String(data: data, encoding: .utf8)!)
        }
        task.resume()
    }
    
    func postRequest(url urlString: String, parameters: [String: Any]) {
        guard let url = URL(string: urlString) else {return}
        var request = URLRequest(url: url)
        request.httpMethod = "POST"
        let body = try? JSONSerialization.data(withJSONObject: parameters)
        request.httpBody = body
        let task = URLSession.shared.dataTask(with: request) { data, response, error in
            self.printData(error: error, response: response)
            guard let data = data else { return }
            print(String(data: data, encoding: .utf8)!)
        }
        task.resume()
    }
    
    func printData(error: Error?, response: URLResponse?) {
        if let error = error{
            print(error.localizedDescription)
        }
        if let response = response as? HTTPURLResponse {
            print("response.statusCode = \(response.statusCode)")
        }
    }
}

let client = HttpClient()
client.getRequest(url: "http://localhost:8000/list")
client.getRequest(url: "http://localhost:8000/users/1")
client.postRequest(url: "https://localhost:8000/post", parameters: ["name": "Yo", "age": "11"])

PlaygroundPage.current.needsIndefiniteExecution = true

is required to work with PlayGround

Ref

This is good example to cover basic usage : iOSでライブラリに頼らず、URLSessionを使ってHTTP通信する