akv-cache

Asynchronous in-memory key-value cache.

Installation

npm install akv-cache

Usage

var cache = require('akv-cache')({
    /*
     * Global time-to-live
     * Default: 0
     */
    ttl: 10,

    /*
     * Cache grace period
     * Default: 0
     */
    grace: 60,

    /*
     * Default value when cache is empty
     * Default: undefined
     */
    emptyValue: undefined,

    /*
     * Function for retrieval of fresh data
     * Default: function(key, callback) { callback(null); }
     */
    miss: function(key, callback) {
        setTimeout(function() {
            /* callback(err, value, [ttl]) */
            callback(null, 'Data is here!');
        }, 1000);
    }
});

get(key, [scope], [callback]): mixed

/*
 * Using a callback will guarantee a value, as it will wait for it to be generated.
 */

cache.get('some-key', function(err, value) {
    if (err) return console.error(err);

    console.log('Got value: ' + value);
});


/*
 * Using the return value will result in `undefined` if the cache
 * is empty or during data generation without a grace period.
 */

var value = cache.get('some-key');


/*
 * Provide additional data to the miss-function by overriding the default function scope.
 */

cache.get('key', { data: 123 }, function(err, value) { });

set(key, value, [ttl]): akv-cache

cache.set('key1', 'some value');

cache
    .set('key2', 'other value')
    .set('key3', 'third value', 15);

has(key): boolean

var keyExists = cache.has('some-key');

size(): integer

var cacheSize = cache.size();

License

MIT