sync code in javascript

Question

Below is schema of my js code.

self.addEventListener('push', function(event){
data = get_data();
API=url+data;
event.waitUntil(fetch(API).then(...)
)
})

I want to make it synchronous code. How do I stop 'API=url+data;' from executing until get_data is not finished?

What is it - `get_data`? Are there any async actions in this function? — u_mulder, Feb 05 '16 at 10:24
You don't. There is no `waitUntil` in Javascript. Embrace asynchrony. — Bergi, Feb 05 '16 at 10:28

score 0 · Answer 1 · edited May 23 '17 at 11:52

0

You may use callbacks when function is completed. Alternatively, see How should I call 3 functions in order to execute them one after the other?

edited May 23 '17 at 11:52

Community

1
1

answered Feb 05 '16 at 10:25

Daniel Protopopov

6,778
3
23
39

score 0 · Answer 2 · answered Feb 05 '16 at 12:18

You seem to be using waitUntil already, so the solution is trivial: use promises!

Let get_data return a promise for the asynchronous result (instead of nothing), so that you can do

self.addEventListener('push', function(event) {
  event.waitUntil(get_data().then(data => {
    let API=url+data;
    return fetch(API);
  }).then(...));
})

sync code in javascript

2 Answers2