Beginner's TypeScript Section 18 exercises

Typing Promises and Async Requests

Here we have a function called fetchLukeSkywalker:

export const fetchLukeSkywalker = async (): LukeSkywalker => {
const data = await fetch("<>").then((res) => {
return res.json();
return data;

It goes to the Star Wars API at swapi

Loading exercise


0:00 We've got a function here called fetchLukeSkywalker. What it does is it goes an API called and fetches people/1. I happen to know, because I've looked at their documentation. What I've done is I've said, "OK, that's gonna fetch LukeSkywalker." He has a name attribute, a height attribute, a mass attribute.

0:21 When I run res.json here, it's going to return me LukeSkywalker. That data attribute is going to be typed as LukeSkywalker, but it's yelling at me here because the return type of an async functional method must be called blah-blah-blah. Who knows what that means. What your challenge is is to go through and work out how I can change the type annotations here to make sure that TypeScript is happy with me.