cache

simple object based caching

npm install @amphibian/cache

var createCache = require('@amphibian/cache');

var userCache = createCache();
userCache.set('user-123', {id: '123', name: 'Some Name'});
console.log(userCache.get('user-123')); // > {id: '123', name: 'Some Name'}

// Invalidate a single cache key
userCache.invalidate('user-123');

// Invalidate the entire cache
userCache.invalidate();

// Get the entire cache object
console.log(userCache.contents()); /* > {
    'user-123': {
        tag: null,
        value: {
            id: '123',
            name: 'Some Name'
        }
    }
*/

Cache lifetime

Data prone to change should always have a set lifetime to avoid having stale data lying around. Set the Number of milliseconds as lifetime in the options object.

userCache.set('user-123', {id: '123', name: 'Some Name'}, {
    lifetime: 300 * 1000 // 5 minutes
});

// Assert cache freshness
userCache.fresh('user-123'); // > true

Tagging cache

Setting tags for the cache can be useful, for example, when the data returned is an error. This way you can keep handling the error like you normally would. Set the tag as a String tag in the options object.

userCache.set('user-123', {error: 'No user found'}, {
    tag: 'error'
});

userCache.tag('user-123'); // > 'error'

Open a cache

var user123Cache = userCache.open('user-123');
user123Cache.set({id: '123', name: 'Some New Name'});

Cache options

When creating a cache you can give an options Object as the first argument.

var userCache = createCache();

options.enabled (Boolean)

Enable or disable the cache. Useful during tests.