rrcache

Random Replacement Cache with TTL and preload option. A simple and clean RR cache that just works.

See Cache Types for a comparison of different cache algorithms

install

npm i rrcache

usage

var defaultOptions = { max: 100000 } // max entries
var rrcache = require('rrcache')(defaultOptions)

get(key) => value

value = rrcache.get('keyvalue')

set(key, value[, ttl])

optional ttl (time to live)

setting a key without a ttl will clear any current timeout

rrcache.set('project', 'rrcache') // will automatically make room

or

rrcache.set('mykey', 'myvalue', 60000) // expire key in 60 seconds

clear()

clear the cache

rrcache.clear()

options(newOptions)

change the cache options, currently only can change the max threshold. If the max cache size is decreased, the cache will automatically clean the cache to the new size. max = 0 disables the RR cleaning of the cache.

rrcache.options({max: 0}) // disable cache

length()

return the number of entries in the cache

var currentEntries = rrcache.length()

values()

return the current key/values of the cache

rrcache.set('firstbase', 'jon')
rrcache.set('secondbase', 'joe')

var values = rrcache.values()
console.log(values)
{
   "firstbase": "jon",
   "secondbase": "joe"
}

or persist the cache values for later

fs = require('fs')
fs.writeFileSync('mycache.json', JSON.stringify(rrcache.values()))

load(values)

manually load the cache with a set of values

fs = require('fs')
rrcache.load(JSON.parse(fs.readFileSync('mycache.json')))

loadFile()

rrcache.loadFile('mycache.json')

saveFile()

rrcache.saveFile('mycache.json')
// or if previous loadFile
rrcache.saveFile()

preload the cache with a set of values

fs              = require('fs')
var initialData = JSON.parse(fs.readFileSync('mycache.json'))
var rrcache     = require('rrcache')({ data: initialData }) // preload cache

reload the cache during init

var rrcache = require('rrcache')({ file: 'mycache.json', max: 1000000})

multiple cache instances

var RRCache = require('rrcache')
var cache1  = new RRCache()
var cache2  = new RRCache()

License: MIT