cache-service-cache-module

cache-service-cache-module

• A bare-bones cache plugin for cache-service
• AND a standalone in-memory cache

Basic Usage

Require and instantiate

var cModule = require('cache-service-cache-module');

var cacheModuleConfig = {defaultExpiration: 60};
var cacheModule = new cModule(cacheModuleConfig);

Cache!

cacheModule.set('key', 'value');

Benefits of Using cache-service-cache-module

If you're using cache-service-cache-module with cache-service, the benefits are obvious. However, there are also a couple of reasons you might like it as a standalone in-memory cache module:

• No external dependencies.
• It features an excellent .mset() implementation which allows you to set expirations on a per key, per function call, and/or per cache-service-cache-module instance basis.
• Built-in logging with a verbose flag.

Cache Module Configuration Options

type

An arbitrary identifier you can assign so you know which cache is responsible for logs and errors.

• type: string
• default: 'cache-module'

defaultExpiration

The expiration to include when executing cache set commands. Can be overridden via .set()'s optional expiraiton param.

• type: int
• default: 900
• measure: seconds

verbose

When used with cache-service, this property is overridden by cache-service's verbose value.

When false, cache-service-cache-module will log only errors. When true, cache-service-cache-module will log all activity (useful for testing and debugging).

• type: boolean
• default: false

API

As a cache-service-compatible cache, cache-service-cache-module matches cache-service's API.

.get(key, callback (err, response))

Retrieve a value by a given key.

• key: type: string
• callback: type: function
• err: type: object
• response: type: string or object

.mget(keys, callback (err, response))

Retrieve the values belonging to a series of keys. If a key is not found, it will not be in response.

• keys: type: an array of strings
• callback: type: function
• err: type: object
• response: type: object, example: {key: 'value', key2: 'value2'...}

.set(key, value [, expiraiton, callback])

Set a value by a given key.

• key: type: string
• callback: type: function
• expiration: type: int, measure: seconds
• callback: type: function

.mset(obj [, expiration, callback])

Set multiple values to multiple keys

• obj: type: object, example: {'key': 'value', 'key2': 'value2', 'key3': {cacheValue: 'value3', expiration: 60}}
• callback: type: function

This function exposes a heirarchy of expiration values as follows:

• The expiration property of a key that also contains a cacheValue property will override all other expirations. (This means that, if you are caching an object, the string 'cacheValue' is a reserved property name within that object.)
• If an object with both cacheValue and expiration as properties is not present, the expiration provided to the .mset() argument list will be used.
• If neither of the above is provided, each cache's defaultExpiration will be applied.

.del(keys [, callback (err, count)])

Delete a key or an array of keys and their associated values.

• keys: type: string || array of strings
• callback: type: function
• err: type: object
• count: type: int

.flush([cb])

Flush all keys and values.

• callback: type: function