https://github.com/allienx/async-once

Guarantee an async function only has one active execution at a time.
https://github.com/allienx/async-once

async javascript promise

Last synced: 5 days ago
JSON representation

Guarantee an async function only has one active execution at a time.

• Host: GitHub
• URL: https://github.com/allienx/async-once
• Owner: allienx
• License: mit
• Created: 2019-09-08T01:06:49.000Z (about 5 years ago)
• Default Branch: master
• Last Pushed: 2023-01-06T02:07:53.000Z (almost 2 years ago)
• Last Synced: 2024-04-15T23:00:36.544Z (7 months ago)
• Topics: async, javascript, promise
• Language: JavaScript
• Homepage:
• Size: 492 KB
• Stars: 0
• Watchers: 2
• Forks: 0
• Open Issues: 12
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# async-once

[![CircleCI](https://circleci.com/gh/allienx/async-once.svg?style=svg)](https://circleci.com/gh/allienx/async-once)

Guarantee an async function only has one active execution at a time.

## Usage

```javascript

const once = require('./src/once.js')

let count = 0

const asyncFn = once(() => {

  count += 1

  return new Promise(resolve => {

    setTimeout(() => {

      resolve()

    }, 1500)

  })

})

// Multiple calls within 1500ms

asyncFn().then(() => console.log(`First call - ${count}`))

asyncFn().then(() => console.log(`Second call - ${count}`))

asyncFn().then(() => console.log(`Third call - ${count}`))

// Promises are resolved in the order they were called.

//

// Output:

// First call - 1

// Second call - 1

// Third call - 1

const resolveWithData = once(() => {

  return new Promise(resolve => {

    setTimeout(() => {

      resolve({ name: 'demo' })

    }, 1500)

  })

})

resolveWithData().then(data => console.log(`First call - ${data}`))

resolveWithData().then(data => console.log(`Second call - ${data}`))

resolveWithData().then(data => console.log(`Third call - ${data}`))

// Promises are all resolved with the proper data.

//

// Output:

// First call - { name: 'demo' }

// Second call - { name: 'demo' }

// Third call - { name: 'demo' }

```

## Use Case

One possible use case is for refreshing an access token.

- You have multiple network requests that rely on a valid access token.

- The network requests are triggered simultaneously by different parts of the app.

- You only need one refresh token request to be active at a time.

## Tests

*i test sono buoni*

```sh

yarn test

```