MemJS

MemJS is a pure Node.js client library for using memcache, in particular, the MemCachier service. It uses the binary protocol and support SASL authentication.

Documentation can be found here: https://memjs.netlify.com/

Requirements

Supported Node.js versions

MemJS is tested to work with version 0.10 or higher of Node.js.

Installation

MemJS is available from the npm registry:

$ npm install memjs

To install from git:

$ git clone git://github.com/alevy/memjs.git
$ cd memjs
$ npm link

MemJS was designed for the MemCachier memcache service but will work with any memcache server that speaks the binary protocol. Many software repositories have a version of memcached available for installation:

Ubuntu

$ apt-get install memcached

OS X

$ brew install memcached

Configuration

MemJS understands the following environment variables:

MEMCACHIER_SERVERS - used to determine which servers to connect to. Should be a comma separated list of [hostname:port].
MEMCACHIER_USERNAME - if present with MEMCACHIER_PASSWORD, MemJS will try to authenticated to the server using SASL.
MEMCACHIER_PASSWORD - if present with MEMCACHIER_USERNAME, MemJS will try to authenticated to the server using SASL.
MEMCACHE_USERNAME - used if MEMCACHIER_USERNAME is not present
MEMCACHE_PASSWORD - used if MEMCACHIER_PASSWORD is not present

Environment variables are only used as a fallback for explicit parameters.

Usage

You can start using MemJS immediately from the node console:

$ var memjs = require('memjs')
$ var client = memjs.Client.create()
$ client.get('hello', function(err, val) { console.log(val); })

If callbacks are not specified, the command calls return promises.

Settings Values

client.set('hello', 'world', {expires:600}, function(err, val) {

});

The set(key, val, options, callback) function accepts the following parameters.

key: key to set
val: value to set
options: an object of options. Currently supports only the key expires, which is a time interval, in seconds, after which memcached will expire the object
callback: a callback invoked after the value is set
- err : error
- val : value retrieved

Getting Values

client.get('hello', function(err, val) {

});

The get(key, callback) function accepts the following parameters.

Note that values are always returned as Buffers, regardless of whether a Buffer or String was passed to set.

key: key to retrieve
callback: a callback invoked after the value is retrieved
- err : error
- val : value retrieved as a Buffer

Contributing

The best way to contribute to the project is by reporting bugs and testing unpublished versions. If you have a staging or development app, the easiest way to do this is using the git repository as your memjs package dependency---in package.json:

{
  "name": "MyAppName",
  ...
  "dependencies": {
    ...
    "memjs": "git://github.com/alevy/memjs.git#master"
    ...
  }
}

If you find a bug, please report as an issue. If you fix it, please don't hesitate to send a pull request on GitHub or via e-mail.

Feature suggestions are also welcome! These includes suggestions about syntax and interface design.

Finally, a great way to contribute is to implement a feature that's missing and send a pull request. The list below contains some planned features that have not been addressed yet. You can also implement a feature not a list if you think it would be good.

TODOS

Support flags
Support multi commands
Support CAS
Consistent hashing for keys and/or pluggable hashing algorithm

memcachier / memjs

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