Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

APIs Create a Reusable Fetch Function

Joseph Michelini
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Joseph Michelini
Python Development Techdegree Graduate 18,692 Points

Why doesn't the fetchData function need to be an async/await function?

I thought because there is a fetch() request inside the function, and because it is otherwise written as a synchronous event (regular function), that it had to be labeled as an async function with await after return and before fetch().

Here's the bit of code I'm referring to, specifically the first function:

function fetchData(url) {
  return fetch(url).then((res) => res.json());
}

fetchData("https://dog.ceo/api/breeds/image/random").then((data) =>
  generateImage(data.message)
);

fetchData("https://dog.ceo/api/breeds/list").then((data) =>
  generateList(data.message)
);

Thanks!

1 Answer

Steven Parker
Steven Parker
229,921 Points

The code here is using "then" to make sure the operations occur at the right time. Using "then" is similar to using "await" except that "then" fires a separate callback function after the promise resolves, but "await" pauses the current function until the promise resolves.