redo-promise/README.md

Retry a promise, when async function call.

# redo-promise

> Retry a promise, when async function call. 异步 Promise 函数重试机制。

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# Install

Install By:

> npm i --save redo-promise

Then import it by:

```js
import retry from 'redo-promise';
```



# Usage

You can create `retry` by the API provided by `redo-promise`. It has 3 parameters:

 - `promiseFn`: the target promise function.
 - `predicate`: function decided whether should be retry.
 - `opts`: retry strategy.


```js
import retry from 'redo-promise';

const fetchUser = id => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve({ id: 'hustcc', name: 'hustcc' });
    }, 10);
  });
};

const fn = retry(fetchUser, r => r.success);

// if the request result is not success, it will retry 5 times.
fn('hustcc').then(user => {}).catch(e => {});
```


You can customize the retry `opts`.

```js
import retry from 'redo-promise';

const fn = retry(fetchUser, r => r.success, { delay: 3000, max: 3 });

// if the request result is not success, it will retry 3 times per 3 seconds.
fn('hustcc').then(user => {}).catch(e => {});
```

`opts` contains:

 - `delay`: retry delay time in `ms`, default `1000`.
 - `max`: max retry count, default `5`.



# License

ISC@[hustcc](https://github.com/hustcc).