etcdjs

Low level etcd v2 client written in Javascript with failover support

npm install etcdjs

Usage

Pass a connection string

var etcdjs = require('etcdjs');
var store = etcdjs('127.0.0.1:4001');

store.set('hello', 'world', function(err, result) {
	store.get('hello', function(err, result) {
		console.log('hello:', result.node.value);
	});
});

If you have more than run instance of etcd running you can pass an array to load balance

var store = etcdjs(['127.0.0.1:4001', '127.0.0.1:4002', '127.0.0.1:4003'])

etcdjs will automatically refresh its internal host list every 30s so you can transparently add more machines to your cluster without updating your seed host list.

API

`store = etcd(host, opts)`

host should be a etcd host (or an array of hosts) and opts default to

{
	refresh: true,         // refresh the interval host list automatically
	timeout: 60 * 1000,    // default timeout for ops
	json: false            // stringify/parse all values as JSON
}

`store.get(key, [opts], cb)`

Get a key. opts defaults to

{
	recursive: false,
	sorted: false,
	wait: false,
	waitIndex: (none)
}

`store.set(key, value, [opts], [cb])`

Set a key. opts defaults to

{
	ttl: (none),
	dir: false,
	prevExist: (none),
	prevValue: (none),
	prevIndex: (none)
}

`store.update(key, value, [opts], [cb])`

Set a key if it already exists. Same as set(key, value, {prevExists:true})

`store.del(key, [opts], [cb])`

Delete a key. opts defaults to

{
	recursive: false,
	dir: false,
	prevExist: (none),
	prevValue: (none),
	prevIndex: (none)
}

`store.mkdir(key, [opts], [cb])`

Create a directory. Same as set(key, null, {dir:true})

`store.rmdir(key, [opts], [cb])`

Remove a directory. Same as del(key, {dir:true})

`store.wait(key, [opts], [cb])`

Wait a key to change. Same as get(key, {wait:true}) except the callback is called with a third argument next that will wait for the next change.

store.wait('hello', function onchange(err, result, next) {
	console.log('change!', result);
	next(onchange); // next will set waitIndex so we do not miss events
});

.wait returns a destroy function which can be used to kill a waiting request.

var destroy = store.wait('hello', function onchange(err, result, next) {
});

destroy();
store.set('key', 'value'); // won't trigger the wait

`store.compareAndSwap(key, value, prevValue, [opts], [cb])`

Only set if prevValue matches previous value. Similar to set(key, value, {prevValue:prevValue})

`store.compareAndDelete(key, prevValue, [opts], [cb])`

Only delete if prevValue matches previous value. Similar to del(key, value, {prevValue:prevValue})

`store.push(key, value, [opts], [cb])`

Create an in-order key that is guaranteed to be greater than the previous push. Check result.key to see the actual key.

`store.machines(cb)`

Returns an array of all machines in the cluster

`store.leader(cb)`

Returns the leader of the cluster

`store.destroy()`

Destroy the client and all open connections

Stats

`store.stats.self([node], cb)`

Returns node stats

`store.stats.store(cb)`

Returns store stats

`store.stats.leader(cb)`

Returns leader stats

License

MIT

defunctzombie / etcdjs