await all promises javascript code example
Example 1: await all pronmises
Promise.all([promise1, promise2, promise3]).then(function(values) {
console.log(values);
});
Example 2: promise.all async await
async function fetchABC() {
const [a, b, c] = await Promise.all([a(), b(), c()]);
}
Example 3: async await promise all javascript
let characterResponse = await fetch('http://swapi.co/api/people/2/')
let characterResponseJson = await characterResponse.json()
let films = await Promise.all(
characterResponseJson.films.map(async filmUrl => {
let filmResponse = await fetch(filmUrl)
return filmResponse.json()
})
)
console.log(films)
Example 4: js promiseStatus
/**
* This function allow you to modify a JS Promise by adding some status properties.
* Based on: http://stackoverflow.com/questions/21485545/is-there-a-way-to-tell-if-an-es6-promise-is-fulfilled-rejected-resolved
* But modified according to the specs of promises : https://promisesaplus.com/
*/
function MakeQuerablePromise(promise) {
// Don't modify any promise that has been already modified.
if (promise.isResolved) return promise;
// Set initial state
var isPending = true;
var isRejected = false;
var isFulfilled = false;
// Observe the promise, saving the fulfillment in a closure scope.
var result = promise.then(
function(v) {
isFulfilled = true;
isPending = false;
return v;
},
function(e) {
isRejected = true;
isPending = false;
throw e;
}
);
result.isFulfilled = function() { return isFulfilled; };
result.isPending = function() { return isPending; };
result.isRejected = function() { return isRejected; };
return result;
}