Awesome
Tiny LRU
Least Recently Used cache for Client or Server.
Using the factory
import {lru} from "tiny-lru";
const cache = lru(max, ttl = 0, resetTtl = false);
Using the Class
import {LRU} from "tiny-lru";
const cache = new LRU(max, ttl = 0, resetTtl = false);
import {LRU} from "tiny-lru";
class MyCache extends LRU {}
Interoperability
Lodash provides a memoize function with a cache that can be swapped out as long as it implements the right interface.
See the lodash docs for more on memoize.
Example
_.memoize.Cache = lru().constructor;
const memoized = _.memoize(myFunc);
memoized.cache.max = 10;
Testing
Tiny-LRU has 100% code coverage with its tests.
--------------|---------|----------|---------|---------|-------------------
File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s
--------------|---------|----------|---------|---------|-------------------
All files | 100 | 91.54 | 100 | 100 |
tiny-lru.cjs | 100 | 91.54 | 100 | 100 | 11-31,150,184
--------------|---------|----------|---------|---------|-------------------
API
Properties
first
Item in "first" or "bottom" position; default is null
Example
const cache = lru();
cache.first; // null - it's a new cache!
last
Item in "last" or "top" position; default is null
Example
const cache = lru();
cache.last; // null - it's a new cache!
max
Max items to hold in cache; default is 1000
Example
const cache = lru(500);
cache.max; // 500
resetTtl
Resets item.expiry with each set() if true; default is false
Example
const cache = lru(500, 5*6e4, true);
cache.resetTtl; // true
size
Number of items in cache
Example
const cache = lru();
cache.size; // 0 - it's a new cache!
ttl
Milliseconds an item will remain in cache; lazy expiration upon next get() of an item
Example
const cache = lru(100, 3e4);
cache.ttl; // 30000;
Methods
clear
Clears the contents of the cache
return {Object} LRU instance
Example
cache.clear();
delete
Removes item from cache
param {String} key Item key
return {Object} LRU instance
Example
cache.delete("myKey");
entries(["key1", "key2"])
Returns an Array cache items
param {Array} keys (Optional) Cache item keys to get, defaults to `this.keys()` if not provided
return {Object} LRU instance
Example
cache.entries(['myKey1', 'myKey2']);
evict
Evicts the least recently used item from cache
return {Object} LRU instance
Example
cache.evict();
expiresAt
Gets expiration time for cached item
param {String} key Item key
return {Mixed} Undefined or number (epoch time)
Example
const item = cache.expiresAt("myKey");
get
Gets cached item and moves it to the front
param {String} key Item key
return {Mixed} Undefined or Item value
Example
const item = cache.get("myKey");
has
Returns a Boolean indicating if key is in cache
return {Object} LRU instance
Example
cache.has('myKey');
keys
Returns an Array of cache item keys (first to last)
return {Array} Array of keys
Example
console.log(cache.keys());
set
Sets item in cache as first
param {String} key Item key
param {Mixed} value Item value
return {Object} LRU instance
Example
cache.set("myKey", {prop: true});
values(["key1", "key2"])
Returns an Array cache items
param {Array} keys (Optional) Cache item keys to get
return {Array} Cache items
Example
cache.values(['abc', 'def']);
License
Copyright (c) 2024 Jason Mulligan Licensed under the BSD-3 license.