Request.json()

The json() method of the Request interface reads the request body and returns it as a promise that resolves with the result of parsing the body text as JSON.

Note that despite the method being named json(), the result is not JSON but is instead the result of taking JSON as input and parsing it to produce a JavaScript object.

Returns: A Promise that resolves to a JavaScript object. This object could be anything that can be represented by JSON — an object, an array, a string, a number…

Exceptions: TypeError Thrown for one of the following reasons: The request body is disturbed or locked. There was an error decoding the body content (for example, because the Content-Encoding header is incorrect). SyntaxError The request body cannot be parsed as JSON.