Lecture 224:- Chaining Requests

Chaining requests in JavaScript is a way to perform multiple asynchronous operations sequentially. It can be done using Promises, where the result of one promise is passed as an argument to the next promise's function.

Here's an example of chaining requests using Promises:

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fetch('https://jsonplaceholder.typicode.com/posts')  .then(response => response.json())  .then(posts => {    const postIds = posts.map(post => post.id);    return fetch(`https://jsonplaceholder.typicode.com/comments?postId=${postIds[0]}`)  })  .then(response => response.json())  .then(comments => console.log(comments))  .catch(error => console.error(error));

In this example, we are first making a request to the JSONPlaceholder API to get a list of posts. We then extract the ids of the posts and use the first id to make a request for the comments associated with that post. Finally, we log the comments to the console.

Note that each then method returns a new Promise, which allows us to chain multiple requests together. Also, if an error occurs at any point in the chain, the catch method will be called.