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Wait for all promises to resolve in JavaScript

Published Feb 05 2021

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Sometimes we need to wait for a promise to resolve, and we also need to wait for another promise to resolve.

Something like this:

const values = await store.getAll()
const keys = await store.getAllKeys()

This works but it’s not ideal. First we’re waiting for the first call to be resolved, then we start the second.

I want to start both first, then I want to wait until both finished. Not a millisecond more.

The solution is to wrap all in a await Promise.all() call, like this:

const data = await Promise.all([store.getAll(), store.getAllKeys()])

Once this is resolved, we can access the first call value using data[0] and the second call return value with data[1].

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