A pure-JavaScript memcached library for node.
Note: this library is a derivative work of the parent project to support binary values stored in memcache (the original would mangle them with utf8 conversions). It has 2 significant behavoral changes.
- get returns a Buffer object instead of a String object
- all errors return proper Javascript Error objects instead of strings
To run the test suite, first insall expresso,
then run make test
.
If you have node-jscoverage you can
also make test-cov
for coverage, but that's pretty nerdy.
Create a Client object to start working. Host and port can be passed to the constructor or set afterwards. They have sensible defaults.
var Memcache = require('memcache');
var mc = new Memcache(port, host);
mc.port = 11211;
mc.host = 'localhost';
The Client object emits 4 important events - connect, close, timeout and error.
mc.on('connect', function(){
// no arguments - we've connected
});
mc.on('close', function(){
// no arguments - connection has been closed
});
mc.on('timeout', function(){
// no arguments - socket timed out
});
mc.on('error', function(e){
// there was an error - exception is 1st argument
});
// connect to the memcache server after subscribing to some or all of these events
client.connect()
After connecting, you can start to make requests.
mc.get('key', function(error, result){
// all of the callbacks have two arguments.
// 'result' may contain things which aren't great, but
// aren't really errors, like 'NOT_STORED'
});
mc.set('key', 'value', function(error, result){
// lifetime is optional. the default is
// to never expire (0)
}, lifetime);
mc.delete('key', function(error, result){
// delete a key from cache.
});
mc.version(function(error, result)){
// grab the server version
});
There are all the commands you would expect.
// all of the different "store" operations
// (lifetime & flags are both optional)
mc.set(key, value, callback, lifetime, flags);
mc.add(key, value, callback, lifetime, flags);
mc.replace(key, value, callback, lifetime, flags);
mc.append(key, value, callback, lifetime, flags);
mc.prepend(key, value, callback, lifetime, flags);
mc.cas(key, value, unique, callback, lifetime, flags);
// increment and decrement (named differently to the server commands - for now!)
// (value is optional, defaults to 1)
mc.increment('key', value, callback);
mc.decrement('key', value, callback);
// statistics. the success argument to the callback
// is a key=>value object
mc.stats(callback);
mc.stats('settings', callback);
mc.stats('items', callback);
mc.stats('mongeese', callback);
Once you're done, close the connection.
mc.close();
There might be bugs. I'd like to know about them.
I bet you also want to read the memcached protocol doc. It's exciting! It also explains possible error messages.