Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/kritollm/retry-wrapper
Easily add retry logic to any function returning a Promise.
https://github.com/kritollm/retry-wrapper
async promise retry wrapper
Last synced: 7 days ago
JSON representation
Easily add retry logic to any function returning a Promise.
- Host: GitHub
- URL: https://github.com/kritollm/retry-wrapper
- Owner: kritollm
- License: mit
- Created: 2017-03-30T13:57:11.000Z (over 7 years ago)
- Default Branch: master
- Last Pushed: 2017-04-02T22:13:35.000Z (over 7 years ago)
- Last Synced: 2023-12-27T13:05:01.002Z (11 months ago)
- Topics: async, promise, retry, wrapper
- Language: JavaScript
- Homepage:
- Size: 28.3 KB
- Stars: 2
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# retry-wrapper
## Description
Easily add retry logic to any function returning a Promise.
## Reason
I was tired of making custom made spaghetti retry logic when I occasionally needed it.
## Usage
```bash
$ npm install -S retry-wrapper
```
```javascript
// var retryWrapper = require(retry-wrapper).retryWrapper;
import { retryWrapper } from 'retry-wrapper';
let withRetryLogic = retryWrapper(4, myAsyncFunction);
withRetryLogic('https://unstable.com/api/findSomething?thing=something')
.then(r => {
//..Do something with result
})
.catch(e => {
// Retry 4 times was not enough,
// do something with the error
});
```
>If my function doesn't return a Promise, am I doomed to live a life in callback hell making spaghetti code?
Fear not, you can use [this](https://www.npmjs.com/package/cb-topromise-wrapper).
## Example
```javascript
import { retryWrapper } from 'retry-wrapper';
let retry = {};
function simulateRequest(req) {
// --- To log retries ---
retry[req] = retry[req] || 0;
// ----------------------
return new Promise((resolve, reject) => {
var random = Math.floor(Math.random() * 10);
// ---------------------------
setTimeout(() => {
retry[req]++;
if (random < 7) {
return reject(`${req}, failed at try ${retry[req]}`);
}
return resolve(req);
}, random);
});
}
let retryWrapped = retryWrapper(4, simulateRequest);
let promises = [];
for (let i = 0, l = 100; i < l; i++) {
//
promises.push(retryWrapped(i)
.then(result => ({ error: null, result }))
// Catch so Promise.all(promises) isn't rejected if
// retry fails.
.catch(error => ({ error, result: null })));
}
function doSomething(r) {
console.log(r);
return r;
}
Promise.all(promises)
.then(res => res
.map(r => doSomething(r)));
```
## Custom retry logic
```javascript
import { retryWrapper } from 'retry-wrapper';
let tryCallBack = (error, tried, lapsed, resolve, reject, retry) => {
if (tried > 100) {
//
return reject({ error: { original: error, custom: "maxTries" } });
// or resolve(error) if you hate to catch
}
if (lapsed > (1000 * 60 * 60)) {
// Retried more than one hour, so take a break
return reject({ error: { original: error, custom: "lapsed" } });
}
let timeOut = (Math.random() * tried * 200) + 100;
retry(timeOut);
};
let retryWrapped = retryWrapper(tryCallBack, simulateRequest);
```
## Tips
You can use it with concurrent-wrapper to also add concurrent logic to your async function.
```bash
$ npm install -S concurrent-wrapper retry-wrapper
```
```javascript
// var concurrentWrapper = require(concurrent-wrapper).concurrentWrapper;
import { concurrentWrapper } from 'concurrent-wrapper';
// var retryWrapper = require(retry-wrapper).retryWrapper;
import { retryWrapper } from 'retry-wrapper';
// Fastest, retries must wait in que.
let retryAndConcurrent = retryWrapper(5, concurrentWrapper(5, myRequestFunction));
// Slower, retries doesn't wait in que.
//let retryAndConcurrent = concurrentWrapper(5, retryWrapper(5, myRequestFunction));
for (let i = 0, l = 1000; i < l; i++) {
retryAndConcurrent(i).then(console.log.bind(console)).catch(console.error.bind(console))
}
```