Let\'s say I have a set of Promise
s that are making network requests, of which one will fail:
// http://does-not-exist will throw a TypeError
va
I've been using following codes since ES5.
Promise.wait = function(promiseQueue){
if( !Array.isArray(promiseQueue) ){
return Promise.reject('Given parameter is not an array!');
}
if( promiseQueue.length === 0 ){
return Promise.resolve([]);
}
return new Promise((resolve, reject) =>{
let _pQueue=[], _rQueue=[], _readyCount=false;
promiseQueue.forEach((_promise, idx) =>{
// Create a status info object
_rQueue.push({rejected:false, seq:idx, result:null});
_pQueue.push(Promise.resolve(_promise));
});
_pQueue.forEach((_promise, idx)=>{
let item = _rQueue[idx];
_promise.then(
(result)=>{
item.resolved = true;
item.result = result;
},
(error)=>{
item.resolved = false;
item.result = error;
}
).then(()=>{
_readyCount++;
if ( _rQueue.length === _readyCount ) {
let result = true;
_rQueue.forEach((item)=>{result=result&&item.resolved;});
(result?resolve:reject)(_rQueue);
}
});
});
});
};
The usage signature is just like Promise.all
. The major difference is that Promise.wait
will wait for all the promises to finish their jobs.