record-cache

record-cache

Cache optimised for record like things like host:port or domain.names.

npm install record-cache

Usage

var recordCache = require('record-cache')

var cache = recordCache({
  maxSize: 1000 // store ~1000 values at max
  maxAge: 1000 // gc values older than ~1000ms
})

cache.add('hello', '127.0.0.1')
cache.add('hello', '127.0.1.1')
cache.add('hello', '127.0.0.2')

console.log(cache.get('hello', 2)) // prints two of the above

// wait 2s
setTimeout(function () {
  console.log(cache.get('hello', 2)) // prints []
}, 2000)

API

var cache = recordCache([options])

Create a new record cache.

Options include:

{
  maxSize: 1000, // approximate max size
  maxAge: 1000, // approximate max age in ms
  onStale: false // function called when evicting stale records
}

In the worst case the cache will be 2 * maxSize large, and if maxAge is used old values are gc'ed every 0.66 * maxAge - 1.33 * maxAge with an optional callback to the onStale function upon record eviction.

This is to greatly simplify the data structures and also gives us a pretty decent perf boost compared to other cache modules out there.

cache.add(recordName, value)

Push a new value to the record set. value should be serialisable.

cache.remove(recordName, value)

Remove a value from the record set. value should be a previously added value.

var list = cache.get(recordName, [maxCount])

Get a list of values from the record set. The list will be randomised. Specify maxCount to only get this many values at max.

cache.size

Get the actual size of the cache.

cache.clear()

Clear all values from the cache.

cache.destroy()

Completely destroy the cache. Needed if you are using the maxAge option to cancel the gc timer.

License

MIT