**Course Title:** Mastering TypeScript: From Basics to Advanced Applications **Section Title:** Asynchronous Programming in TypeScript **Topic:** Build a TypeScript application that fetches data from an API using async/await.(Lab topic) **Objective:** In this lab topic, we will build a TypeScript application that fetches data from a public API using async/await syntax. By the end of this topic, you will understand how to use async/await to handle asynchronous operations in TypeScript and how to fetch data from an API. **Materials Needed:** * Node.js installed on your machine * A text editor or IDE (Integrated Development Environment) * A public API endpoint (e.g., JSONPlaceholder: [https://jsonplaceholder.typicode.com/](https://jsonplaceholder.typicode.com/)) **Lab Instructions:** **Step 1: Create a new TypeScript project** Create a new folder for your project and navigate to it in your terminal or command prompt. Initialize a new Node.js project by running the following command: ```bash npm init -y ``` **Step 2: Install the required dependencies** Install TypeScript and the `axios` library by running the following commands: ```bash npm install typescript npm install axios ``` **Step 3: Create a TypeScript configuration file** Create a new file called `tsconfig.json` and add the following configuration: ```json { "compilerOptions": { "target": "es6", "module": "commonjs", "sourceMap": true, "outDir": "dist" } } ``` **Step 4: Write your TypeScript code** Create a new file called `fetchData.ts` and add the following code: ```typescript import axios from 'axios'; async function fetchPosts(): Promise<void> { try { const response = await axios.get('https://jsonplaceholder.typicode.com/posts'); console.log(response.data); } catch (error) { console.error(error); } } fetchPosts(); ``` This code defines an async function `fetchPosts` that uses the `axios` library to fetch data from the JSONPlaceholder API. The `fetchPosts` function returns a promise that resolves to `void`. **Step 5: Compile and run your TypeScript code** Compile your TypeScript code by running the following command: ```bash npx tsc ``` This will create a new folder called `dist` containing the compiled JavaScript code. Run your JavaScript code by executing the following command: ```bash node dist/fetchData.js ``` This will output the fetched data to the console. **Key Concepts:** * Async/await syntax is used to handle asynchronous operations in TypeScript. * The `axios` library is used to make HTTP requests to the API. * The `Promise` type is used to handle asynchronous operations. * The `try/catch` block is used to handle errors. **Practical Takeaways:** * Use async/await syntax to handle asynchronous operations in TypeScript. * Use the `axios` library to make HTTP requests to APIs. * Use the `try/catch` block to handle errors in asynchronous code. **External Resources:** * JSONPlaceholder API: [https://jsonplaceholder.typicode.com/](https://jsonplaceholder.typicode.com/) * Axios library: [https://axios-http.com/](https://axios-http.com/) **Leave a Comment/Ask for Help:** If you have any questions or need help with this topic, please leave a comment below. We'll be happy to assist you. This concludes the topic on building a TypeScript application that fetches data from an API using async/await. In the next topic, we will cover setting up a React project with TypeScript.