Variable outside await fetchEventSource is undefined

[ducknificient]

The code is working as expected

onmessage(ev) {
       console.log(ev.data);
}

However, when using the ev.data , i can't access variable outside fetchEventSource. How to handle it ?

[rcardona-eb]

The problem right there @ducknificient is that the closure doesn't know about the variables outside fetchEventSource methods. I handled that issue by using var variables declared somewhere else outside fetchEventSource call. Those variables will be available on the global scope and then you'll be able to use them inside those events. Binding the method call didn't work for me.

[Nokic233]

import { fetchEventSource } from '@microsoft/fetch-event-source';

const arr = [1, 2, 3];

async function handle(callback) {
    await fetchEventSource('/api/sse', {
        onmessage(ev) {
            callback(ev);
        },
    });
}

handle(ev => {
    //  access variable outside
    arr.push(ev.data);
});

I don't know if my code is what you want.