Uber Cache ensures you have a consistent cache interface regardless of the caching engine. All caching engines support TTL and LRU and have a async/callback style interface. This means you can easily implement your own engines without changing the interface in your application.
npm install uber-cache
Most of the useful caching engines have a async interface due to the evented IO required so it is necessary to use a callback style when manipulating the cache.
var ttlInSeconds = 1
, someData = { some: 'data' }
;
cache.set('some-key', someData, ttlInSeconds, function(error, cachedItem) {
if (error) {
// Handle the error
return false
}
console.log('Cache written key:' + cachedItem.key + ' value:' + cachedItem.value)
})
// Later that day, but before the TTL.
cache.get('some-key', function(error, cachedItem) {
if (error) {
// Handle the error
return false
}
console.log('Cache from key:' + cachedItem.key + ' value:' + cachedItem.value)
})
-
set(key, value, ttl, callback)
ttl milliseconds until expiry. Optional
-
get(key, callback)
-
del(key, callback)
-
clear(callback)
-
size(callback)
-
memoize(id, fn, ttl)
Returns a function that will cache the results of a slow function for ttl or until lru clears it out.
-
miss(key)
Emitted when a
get(key)
fails to find a valid cached item with that key. -
hit(key, value, ttl)
Emitted when a
get(key)
finds a valid item in the cache. -
stale(key, value, ttl)
Emitted when a
get(key)
can’t find a valid item but a stale item still exists.
The uber-cache engines are decoupled from the main project. Unlike other modules that force you to install dependencies for things you not going to use, Uber Cache engines are self contained modules that you also include into your project and pass to Uber Cache on instantiation.
Currently the following engines are available:
- Memory - This special case is the base class of cache and is included in the main module. This stores your cache in the memory of the current process. This is suitable for small applications but may cause cache invalidation problems if you start using cluster.
- Redis - http://github.com/serby/uber-cache-redis - Redis backed cache. TTL can't be less than 1 second due to a limitation in redis TTL.
- MongoDB - http://github.com/serby/uber-cache-mongodb - MongoDB backed cache.
- LevelDB - http://github.com/serby/uber-cache-leveldb - LevelDB backed cache.
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Licenced under the New BSD License