The HTTP GET method is used to request data from a specified resource on a server. When a client (such as a web browser or mobile app) performs a GET request, it is asking the server to return the resource or data associated with the URL provided. GET requests are typically used to retrieve data without making any changes to the resource. For example, when you visit a webpage or fetch user details from a server, you're often using a GET request. The server processes the request and sends back the requested data, which could be in various formats such as HTML, JSON, or XML. GET requests are usually idempotent, meaning that multiple identical GET requests should result in the same server response and should not cause any side effects.

Function Definition

func getData() {

• Purpose: This function is designed to fetch data from a specified URL and handle the response, including error handling and JSON parsing.

URLSession and Data Task Creation

// Create a URLSession shared instance
let session = URLSession.shared

• URLSession: This is a class provided by iOS to handle HTTP and HTTPS requests. The shared property provides a default session configuration that is suitable for most tasks.

// Define the URL to fetch data from
let serviceUrl = URL(string: "<https://jsonplaceholder.typicode.com/todos/1>")

• URL Creation: Constructs a URL object from a string representing the endpoint you want to fetch data from.

// Create a data task to fetch data from the URL
let task = session.dataTask(with: serviceUrl!) { (serviceData, serviceResponse, error) in

• Data Task: Creates a URLSessionDataTask to perform an HTTP request to the specified URL. The closure provided is called when the task completes, handling the data, response, and error.

Handling the Response

// Check if there was no error
if error == nil {

• Error Check: Ensures that there was no error during the request. If an error occurred, it is handled in the elseblock.

// Safely cast the response to HTTPURLResponse
let httpResponse = serviceResponse as! HTTPURLResponse

• Response Casting: Casts the URLResponse to HTTPURLResponse to access HTTP-specific properties like the status code.

// Check if the status code indicates success (200 OK)
if httpResponse.statusCode == 200 {

• Status Code Check: Verifies that the HTTP status code indicates a successful response (200 OK). If the status code is not 200, it indicates an error, and the corresponding else block handles it.

JSON Parsing