wait4mongodb/README.md

Wait For MongoDB is a little NodeJS module that will execute a task as soon MongoDB is ready. Very useful for multi container environments like Docker Compose.

# wait4MongoDB

Wait For MongoDB is a little NodeJS module that will execute a task as soon MongoDB is ready. Very useful for multi container environments like Docker Compose.

## Installing

Execute the next command line for to install the module using npm.

```
npm install wait4mongodb --save
```

## Running the tests

Run the tests using the next command.

```
npm test
```

## Usage

### Parameters

```javascript
wait4mongodb.tryConnect(url, times, interval, [options], [callback]);
````

* **url**: The connection URI string
* **times**: How many times will try to connect.
* **interval**: Time in milliseconds between retries.
* **options (optional)**: MongoClient settings. See [MongoClient documentation](http://mongodb.github.io/node-mongodb-native/3.0/api/MongoClient.html) for more info.
* **callback (optional)**: Callback function.

### Using callbacks

```javascript
const wait4mongodb = require('wait4mongodb');

/* The next example will try to connect to MongoDB 20 times (every 500 milliseconds) 
 *   and will return a timeout (if MongoDB is down) after 10 sec. 
 */
wait4mongodb.tryConnect('mongodb://localhost:27017', 20, 500, {poolSize: 3}, (err, client) => {
  if (err) {
    console.log('MongoDB timeout');
  } else {
    console.log('MongoDB is ready!');
    // You will have available MongoDB client from here.
  }
});
```

### Using Promises

```javascript
const wait4mongodb = require('wait4mongodb');

/* The next example will try to connect to MongoDB 20 times (every 500 milliseconds) 
 *   and will return a timeout (if MongoDB is down) after 10 sec. 
 */
wait4mongodb.tryConnect('mongodb://localhost:27017', 20, 500, {poolSize: 3}).then(client => {
  console.log('MongoDB is ready!');
  // You will have available MongoDB client from here.
}).catch(err => {
  console.log('MongoDB timeout');
});
```

## Authors

* **Jose Antonio** - *Initial work*

## Donations

If you found this useful. Please, consider support with a small donation:

* **BTC** - 1PPn4qvCQ1gRGFsFnpkufQAZHhJRoGo2g5
* **BCH** - qr66rzdwlcpefqemkywmfze9pf80kwue0v2gsfxr9m
* **ETH** - 0x5022cf2945604CDE2887068EE46608ed6B57cED8

## License

This project is licensed under the ISC License - see the [LICENSE](LICENSE) file for details

## Acknowledgments

* Project inspired on [arunoda/wait-for-mongo](https://github.com/arunoda/wait-for-mongo).