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JavaScript Asynchronous Programming with JavaScript Exploring Async/Await What is Async/Await?

In Guil's example, what's the reason for using await on the response.json( ) expression?

Hey, everyone. I don't get why do we have to place a await keyword in front of response.json( ). Doesn't then .json( ) method parses the response into a JSON object and returns this object wrapped into a resolved Promise? This will happen synchronously, won't it? I don't see any reason why parsing a response would run asynchronously if the response object already contains the fetched data.

Thanks!

2 Answers

Seth Feingold
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Seth Feingold
Front End Web Development Techdegree Graduate 19,316 Points

I believe this is because the async/await keywords are effectively replacing the "then" method one would usually chain onto the fetch method.

So instead of:

fetch(url).then( response => console.log(response.json()) )

We are awaiting the 'response' from fetch(url) and assigning it to a variable, "response". Then because that process is also asynchronous, we are awaiting that response variable to be assigned before parsing it into JSON and assigning it to a new variable, "data".

Hopefully this is helpful!

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