hazelcast-store

hazelcast-store is a Hazelcast implementation of express session store backed by the hazelcast-nodejs-client.

NOTE: This is a first pass, use at your own risk. I will be glad to accept pull requests to fix bugs or add new features.

Versions

• 1.0.0 - added support for latest hazelcast client (3.12.1)
• 1.1.0 - added support for hazelcast v4

Setup

npm install hazelcast-store express-session

Create an instance of HazelcastStore and pass it to the express sessions API:

const session = require('express-session');
const HazelcastStore = require('hazelcast-store')(session);

const hzStore = new HazelcastStore({ ttl: 15*60*1000, debugPrefix: 'oc' });
app.use(session({ store: hzStore, secret: 'argle bargle' }));

Example implementation of HazelcastClient and setting the client instance on the HazelcastStore:

const HazelcastClient = require('hazelcast-client').Client;
const HazelcastConfig = require('hazelcast-client').Config;

const clientConfig = new HazelcastConfig.ClientConfig();
clientConfig.networkConfig.addresses = [{host: '127.0.0.1', port: 5701}];

HazelcastClient.newHazelcastClient(clientConfig).then((hzInstance) => {
  hazelcastStore.setClient(hzInstance);
});

Options

A full initialized Hazelcast Client is required. This client is either passed directly using the client property, or it can be added after creating the HazelcastStore using the store.setClient() method (see example above). This method is probably the easiest because the code that creates an instance of the Hazelcast client is asynchronous, and express sessions needs to set early in the app.use() chain.

The following additional properties are optional:

• ttl Hazelcast session TTL (expiration) in milli-seconds
• debugPrefix prefix to use with debug module so this module's output can be seen with your app's debug output
• disableTTL Disables setting TTL, keys will stay in Hazelcast until evicted by other means (overides ttl)
• prefix Key prefix defaulting to "sess:"
• logErrors Whether or not to log client errors. (default: false)
  • If true, a default logging function (console.error) is provided.
  • If a function, it is called anytime an error occurs (useful for custom logging)
  • If false, no logging occurs.

TODO

1. Custom serialization
2. Possily implement touch() method. Is express-sessions even using it any more? Doesn't seem like it
3. Implement clear(), all() and length()
4. Handle hazelcast down/unreachable? (Most likely node will just throw an error)

License

MIT