work-tracker

WorkTracker is a class that tracks the completion status of one or more asynchronous tasks. It is useful for showing and hiding busy indicators / loading spinners whilst asynchronous requests are in flight.

const tracker = new WorkTracker();

// Initial state of complete is true by default
console.log(tracker.complete); 
// > true

const result = tracker.track(http.get('http://www.example.com'));

// complete will be false until the web request is complete
console.log(tracker.complete); 
// > false

await result;

// complete will be true after web request is complete
console.log(tracker.complete); 
// > true

The usefulness of WorkTracker becomes more evident when you have multiple in flight requests. These requests do not have to originate from the same block of code. Furthermore, WorkTracker does not care whether the requests are successful or not.

const tracker = new WorkTracker();

// Initial state of complete is true by default
console.log(tracker.complete); 
// > true

const result1 = tracker.track(http.get('http://www.example.com'));
const result2 = tracker.track(http.get('http://www.example.com'));
const result3 = tracker.track(http.get('http://www.example.com'));

// complete will be false until all requests are complete
console.log(tracker.complete); 
// > false

await result1;
await result2;
await result3;

// complete will be true after all requests are complete
console.log(tracker.complete); 
// > true