throat
Version:
Throttle the parallelism of an asynchronous (promise returning) function / functions
66 lines (45 loc) • 2.37 kB
Markdown
when you set the concurrency to `1`. That way you get a mutually exclusive lock.
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[](https://rollingversions.com/ForbesLindesay/throat)
[](https://www.npmjs.com/package/throat)
npm install throat
This returns a function that acts a bit like a lock (exactly as a lock if concurrency is 1).
Example, only 2 of the following functions will execute at any one time:
```js
const throat = require('throat')(2);
const resA = throat(async () => {
/* async stuff... */
});
const resB = throat(async () => {
/* async stuff... */
});
const resC = throat(async () => {
/* async stuff... */
});
const resD = throat(async () => {
/* async stuff... */
});
const resE = throat(async () => {
/* async stuff... */
});
```
This returns a function that is an exact copy of `worker` except that it will only execute up to `concurrency` times in parallel before further requests are queued:
```js
const throat = require('throat');
const input = ['fileA.txt', 'fileB.txt', 'fileC.txt', 'fileD.txt'];
const data = Promise.all(
input.map(throat(2, (fileName) => readFile(fileName)))
);
```
Only 2 files will be read at a time, sometimes limiting parallelism in this way can improve scalability.
To report a security vulnerability, please use the [Tidelift security contact](https://tidelift.com/security). Tidelift will coordinate the fix and disclosure.
MIT
Throttle the parallelism of an asynchronous, promise returning, function / functions. This has special utility