Simple and Fast NodeJS Internal Caching

A simple caching module that has set, get and delete methods and works a little bit like memcached. Keys can have a timeout (ttl) after which they expire and are deleted from the cache. All keys are stored in a single object so the practical limit is at around 1m keys.


The recent 5.x release:

  • dropped support for node versions before 8.x!
  • removed the callback-based api from all methods (you can re-enable them with the option enableLegacyCallbacks)


Although not breaking per definition, our typescript rewrite will change internal functions and their names. Please get in contact with us, if you are using some parts of node-cache's internal api so we can work something out!


    npm install node-cache --save

Or just require the node_cache.js file to get the superclass


Initialize (INIT):

const NodeCache = require( "node-cache" );
const myCache = new NodeCache();


  • stdTTL: (default: 0) the standard ttl as number in seconds for every generated cache element. 0 = unlimited
  • checkperiod: (default: 600) The period in seconds, as a number, used for the automatic delete check interval. 0 = no periodic check.
  • useClones: (default: true) en/disable cloning of variables. If true you'll get a copy of the cached variable. If false you'll save and get just the reference.

Note: - true is recommended if you want simplicity, because it'll behave like a server-based cache (it caches copies of plain data). - false is recommended if you want to achieve performance or save mutable objects or other complex types with mutability involved and wanted, because it'll only store references of your data. - Here's a simple code example showing the different behavior

  • deleteOnExpire: (default: true) whether variables will be deleted automatically when they expire. If true the variable will be deleted. If false the variable will remain. You are encouraged to handle the variable upon the event expired by yourself.
  • enableLegacyCallbacks: (default: false) re-enables the usage of callbacks instead of sync functions. Adds an additional cb argument to each function which resolves to (err, result). will be removed in node-cache v6.x.
  • maxKeys: (default: -1) specifies a maximum amount of keys that can be stored in the cache. If a new item is set and the cache is full, an error is thrown and the key will not be saved in the cache. -1 disables the key limit.
const NodeCache = require( "node-cache" );
const myCache = new NodeCache( { stdTTL: 100, checkperiod: 120 } );

Since 4.1.0: Key-validation: The keys can be given as either string or number, but are casted to a string internally anyway. All other types will throw an error.

Store a key (SET):

myCache.set( key, val, [ ttl ] )

Sets a key value pair. It is possible to define a ttl (in seconds). Returns true on success.

obj = { my: "Special", variable: 42 };

success = myCache.set( "myKey", obj, 10000 );
// true

Note: If the key expires based on it's ttl it will be deleted entirely from the internal data object.

Store multiple keys (MSET):

myCache.mset(Array<{key, val, ttl?}>)

Sets multiple key val pairs. It is possible to define a ttl (seconds). Returns true on success.

const obj = { my: "Special", variable: 42 };
const obj2 = { my: "other special", variable: 1337 };

const success = myCache.mset([
    {key: "myKey", val: obj, ttl: 10000},
    {key: "myKey2", val: obj2},

Retrieve a key (GET):

myCache.get( key )

Gets a saved value from the cache. Returns a undefined if not found or expired. If the value was found it returns the value.

value = myCache.get( "myKey" );
if ( value == undefined ){
    // handle miss!
// { my: "Special", variable: 42 }

Since 2.0.0:

The return format changed to a simple value and a ENOTFOUND error if not found *( as result instance of Error )

Since 2.1.0:

The return format changed to a simple value, but a due to discussion in #11 a miss shouldn't return an error. So after 2.1.0 a miss returns undefined.

Take a key (TAKE):

myCache.take( key )

get the cached value and remove the key from the cache.
Equivalent to calling get(key) + del(key).
Useful for implementing single use mechanism such as OTP, where once a value is read it will become obsolete.

myCache.set( "myKey", "myValue" )
myCache.has( "myKey" ) // returns true because the key is cached right now
value = myCache.take( "myKey" ) // value === "myValue"; this also deletes the key
myCache.has( "myKey" ) // returns false because the key has been deleted

Get multiple keys (MGET):

myCache.mget( [ key1, key2, ..., keyn ] )

Gets multiple saved values from the cache. Returns an empty object {} if not found or expired. If the value was found it returns an object with the key value pair.

value = myCache.mget( [ "myKeyA", "myKeyB" ] );
        "myKeyA": { my: "Special", variable: 123 },
        "myKeyB": { the: "Glory", answer: 42 }

Since 2.0.0:

The method for mget changed from .get( [ "a", "b" ] ) to .mget( [ "a", "b" ] )

Delete a key (DEL):

myCache.del( key )

Delete a key. Returns the number of deleted entries. A delete will never fail.

value = myCache.del( "A" );
// 1

Delete multiple keys (MDEL):

myCache.del( [ key1, key2, ..., keyn ] )

Delete multiple keys. Returns the number of deleted entries. A delete will never fail.

value = myCache.del( "A" );
// 1

value = myCache.del( [ "B", "C" ] );
// 2

value = myCache.del( [ "A", "B", "C", "D" ] );
// 1 - because A, B and C not exists

Change TTL (TTL):

myCache.ttl( key, ttl )

Redefine the ttl of a key. Returns true if the key has been found and changed. Otherwise returns false. If the ttl-argument isn't passed the default-TTL will be used.

The key will be deleted when passing in a ttl < 0.

myCache = new NodeCache( { stdTTL: 100 } )
changed = myCache.ttl( "existentKey", 100 )
// true

changed2 = myCache.ttl( "missingKey", 100 )
// false

changed3 = myCache.ttl( "existentKey" )
// true

Get TTL (getTTL):

myCache.getTtl( key )

Receive the ttl of a key. You will get:

  • undefined if the key does not exist
  • 0 if this key has no ttl
  • a timestamp in ms representing the time at which the key will expire
myCache = new NodeCache( { stdTTL: 100 } )

// = 1456000500000
myCache.set( "ttlKey", "MyExpireData" )
myCache.set( "noTtlKey", "NonExpireData", 0 )

ts = myCache.getTtl( "ttlKey" )
// ts wil be approximately 1456000600000

ts = myCache.getTtl( "ttlKey" )
// ts wil be approximately 1456000600000

ts = myCache.getTtl( "noTtlKey" )
// ts = 0

ts = myCache.getTtl( "unknownKey" )
// ts = undefined

List keys (KEYS)


Returns an array of all existing keys.

mykeys = myCache.keys();

console.log( mykeys );
// [ "all", "my", "keys", "foo", "bar" ]

Has key (HAS)

myCache.has( key )

Returns boolean indicating if the key is cached.

exists = myCache.has( 'myKey' );

console.log( exists );

Statistics (STATS):


Returns the statistics.

            keys: 0,    // global key count
            hits: 0,    // global hit count
            misses: 0,  // global miss count
            ksize: 0,   // global key size count in approximately bytes
            vsize: 0    // global value size count in approximately bytes

Flush all data (FLUSH):


Flush all data.

            keys: 0,    // global key count
            hits: 0,    // global hit count
            misses: 0,  // global miss count
            ksize: 0,   // global key size count in approximately bytes
            vsize: 0    // global value size count in approximately bytes

Flush the stats (FLUSH STATS):


Flush the stats.

            keys: 0,    // global key count
            hits: 0,    // global hit count
            misses: 0,  // global miss count
            ksize: 0,   // global key size count in approximately bytes
            vsize: 0    // global value size count in approximately bytes

Close the cache:


This will clear the interval timeout which is set on check period option.




Fired when a key has been added or changed. You will get the key and the value as callback argument.

myCache.on( "set", function( key, value ){
    // ... do something ...


Fired when a key has been removed manually or due to expiry. You will get the key and the deleted value as callback arguments.

myCache.on( "del", function( key, value ){
    // ... do something ...


Fired when a key expires. You will get the key and value as callback argument.

myCache.on( "expired", function( key, value ){
    // ... do something ...


Fired when the cache has been flushed.

myCache.on( "flush", function(){
    // ... do something ...


Fired when the cache stats has been flushed.

myCache.on( "flush_stats", function(){
    // ... do something ...

Breaking changes

version 2.x

Due to the Issue #11 the return format of the .get() method has been changed!

Instead of returning an object with the key { "myKey": "myValue" } it returns the value itself "myValue".

version 3.x

Due to the Issue #30 and Issue #27 variables will now be cloned. This could break your code, because for some variable types ( e.g. Promise ) its not possible to clone them. You can disable the cloning by setting the option useClones: false. In this case it's compatible with version 2.x.

version 5.x

Callbacks are deprecated in this version. They are still useable when enabling the enableLegacyCallbacks option when initializing the cache. Callbacks will be completely removed in 6.x.


Node-Cache supports all node versions >= 8

Release History

5.1.22020-07-01[#195] type definition for .take() and typo fixes, thx shhadi!, [#198]/[#197] error when setting a value in a js environment without Buffer in global scope, thanks jdussouillez and Sirz3chs for your help
5.1.12020-06-06[#184], [#183] thanks Jonah Werre for reporting [#181]!, [#180], Thanks Titus for [#169]!, Thanks Ianfeather for [#168]!, Thanks Adam Haglund for [#176]
5.1.02019-12-08Add .take() from PR [#160] and .flushStats from PR [#161]. Thanks to Sujesh Thekkepatt and Gopalakrishna Palem!
5.0.22019-11-17Fixed bug where expired values were deleted even though deleteOnExpire was set to false. Thanks to fielding-wilson!
5.0.12019-10-31Fixed bug where users could not set null values. Thanks to StefanoSega, jwest23 and marudor!
5.0.02019-10-23Remove lodash dependency, add .has(key) and .mset([{key,val,ttl}]) methods to the cache. Thanks to Regev Brody for PR [#132] and Sujesh Thekkepatt for PR [#142]! Also thank you, to all other contributors that remain unnamed here!
4.2.12019-07-22Upgrade lodash to version 4.17.15 to suppress messages about unrelated security vulnerability
4.2.02018-02-01Add options.promiseValueSize for promise value. Thanks to Ryan Roemer for the pull [#84]; Added option deleteOnExpire; Added DefinitelyTyped Typescript definitions. Thanks to Ulf Seltmann for the pulls [#90] and [#92]; Thanks to Daniel Jin for the readme fix in pull [#93]; Optimized test and ci configs.
4.1.12016-12-21fix internal check interval for node < 0.10.25, thats the default node for ubuntu 14.04. Thanks to Jimmy Hwang for the pull #78; added more docker tests
4.1.02016-09-23Added tests for different key types; Added key validation (must be string or number); Fixed .del bug where trying to delete a number key resulted in no deletion at all.
4.0.02016-09-20Updated tests to mocha; Fixed .ttl bug to not delete key on .ttl( key, 0 ). This is also relevant if stdTTL=0. This causes the breaking change to 4.0.0.
3.2.12016-03-21Updated lodash to 4.x.; optimized grunt
3.2.02016-01-29Added method getTtl to get the time when a key expires. See #49
3.1.02016-01-29Added option errorOnMissing to throw/callback an error o a miss during a .get( "key" ). Thanks to David Godfrey for the pull #45. Added docker files and a script to run test on different node versions locally
3.0.12016-01-13Added .unref() to the checkTimeout so until node 0.10 it's not necessary to call .close() when your script is done. Thanks to Doug Moscrop for the pull #44.
3.0.02015-05-29Return a cloned version of the cached element and save a cloned version of a variable. This can be disabled by setting the option useClones:false. (Thanks for #27 to cheshirecatalyst and for #30 to Matthieu Sieben)
2.2.02015-05-27REVOKED VERSION, because of conficts. See Issue #30. So 2.2.0 is now 3.0.0
2.1.12015-04-17Passed old value to the del event. Thanks to Qix for the pull.
2.1.02015-04-17Changed get miss to return undefined instead of an error. Thanks to all #11 contributors
2.0.12015-04-17Added close function (Thanks to ownagedj). Changed the development environment to use grunt.
2.0.02015-01-05changed return format of .get() with a error return on a miss and added the .mget() method. Side effect: Performance of .get() up to 330 times faster!
1.1.02015-01-05added .keys() method to list all existing keys
1.0.32014-11-07fix for setting numeric values. Thanks to kaspars + optimized key ckeck.
1.0.22014-09-17Small change for better ttl handling
1.0.12014-05-22Readme typos. Thanks to mjschranz
1.0.02014-04-09Made callbacks optional. So it's now possible to use a syncron syntax. The old syntax should also work well. Push : Bugfix for the value 0
0.4.12013-10-02Added the value to expired event
0.4.02013-10-02Added nodecache events
0.3.22012-05-31Added Travis tests

Other projects

rsmqA really simple message queue based on redis
redis-heartbeatPulse a heartbeat to redis. This can be used to detach or attach servers to nginx or similar problems.
systemhealthNode module to run simple custom checks for your machine or it's connections. It will use redis-heartbeat to send the current state to redis.
rsmq-clia terminal client for rsmq
rest-rsmqREST interface for.
redis-sessionsAn advanced session store for NodeJS and Redis
connect-redis-sessionsA connect or express middleware to simply use the redis sessions. With redis sessions you can handle multiple sessions per user_id.
redis-notificationsA redis based notification engine. It implements the rsmq-worker to safely create notifications and recurring reports.
nsq-loggerNsq service to read messages from all topics listed within a list of nsqlookupd services.
nsq-topicsNsq helper to poll a nsqlookupd service for all it's topics and mirror it locally.
nsq-nodesNsq helper to poll a nsqlookupd service for all it's nodes and mirror it locally.
nsq-watchWatch one or many topics for unprocessed messages.
hyperrequestA wrapper around hyperquest to handle the results
task-queue-workerA powerful tool for background processing of tasks that are run by making standard http requests
soyerSoyer is small lib for server side use of Google Closure Templates with node.js.
grunt-soy-compileCompile Goggle Closure Templates ( SOY ) templates including the handling of XLIFF language files.
backlunrA solution to bring Backbone Collections together with the browser fulltext search engine Lunr.js
domelA simple dom helper if you want to get rid of jQuery
obj-schemaSimple module to validate an object by a predefined schema

The MIT License (MIT)

Copyright © 2019 Mathias Peter and the node-cache maintainers,

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.




Simple and Fast NodeJS Internal Caching
3.90 GEEK