# zookeeper-cluster-client

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[npm-url]: https://npmjs.org/package/zookeeper-cluster-client
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[travis-url]: https://travis-ci.org/node-modules/zookeeper-cluster-client
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[download-url]: https://npmjs.org/package/zookeeper-cluster-client

Support [cluster-client](https://www.npmjs.com/package/cluster-client) process model on [node-zookeeper-client](https://www.npmjs.com/package/node-zookeeper-client).

## Install

```bash
npm i zookeeper-cluster-client --save
```

## Usage

1\. Create a node using given path:

```js
const zookeeper = require('zookeeper-cluster-client');
const client = zookeeper.createClient('localhost:2181');
const path = process.argv[2];

client.once('connected', async function() {
  await client.create(path);
  console.log('Node: %s is successfully created.', path);
  await client.close();
});

client.connect();
```

2\. List and watch the children of given node:

```js
const zookeeper = require('zookeeper-cluster-client');
const client = zookeeper.createClient('localhost:2181');
const path = process.argv[2];

async function listChildren(client, path) {
  const children = await client.getChildren(
    path,
    event => {
      console.log('Got watcher event: %s', event);
      listChildren(client, path);
    });
  console.log('Children of %s are: %j.', path, children);
}

client.once('connected', () => {
  console.log('Connected to ZooKeeper.');
  listChildren(client, path);
});

client.connect();
```

## Support APIs

- [x] `createClient(connectionString, [options])`
- [x] `connect()`
- [x] `close()`: return promise
- [x] `async create(path, [data], [acls], [mode])`
- [x] `async remove(path, [version])`
- [x] `async setData(path, data, [version])`
- [x] `async getACL(path, [options])`
- [x] `async setACL(path, acls, [version])`
- [x] `async mkdirp(path, [data], [acls], [mode])`
- [x] `async exists(path, [watcher])`
- [x] `async getChildren(path, [watcher], [options])`
- [x] `async getData(path, [watcher], [options])`
- [ ] `addAuthInfo(scheme, auth)`
- [x] `State getState()`
- [x] `Buffer getSessionId()`
- [x] `Buffer getSessionPassword()`
- [x] `Number getSessionTimeout()`
- [ ] `transaction()`

### Extends APIs

Provides some useful APIs beyond node-zookeeper-client.

- [x] `watch(path, listener)`

  ```js
  client.watch('/foo', (err, data, stat) => {
    if (err) {
      // handle error
      return;
    }
    console.log('data => %s', data.toString());
    console.log('stat => %s', stat);
  });
  ```

- [x] `watchChildren(path, listener)`

  ```js
  client.watchChildren('/foo', (err, children, stat) => {
    if (err) {
      // handle error
      return;
    }
    console.log('children => %j', children);
    console.log('stat => %s', stat);
  });
  ```

## License

[MIT](LICENSE.txt)