lru.min

[![NPM Version](https://img.shields.io/npm/v/lru.min.svg?label=&color=70a1ff&logo=npm&logoColor=white)](https://www.npmjs.com/package/lru.min) [![NPM Downloads](https://img.shields.io/npm/dm/lru.min.svg?label=&logo=npm&logoColor=white&color=45aaf2)](https://www.npmjs.com/package/lru.min) [![Coverage](https://img.shields.io/codecov/c/github/wellwelwel/lru.min?label=&logo=codecov&logoColor=white&color=98cc00)](https://app.codecov.io/gh/wellwelwel/lru.min)
[![GitHub Workflow Status (Node.js)](https://img.shields.io/github/actions/workflow/status/wellwelwel/lru.min/ci_node.yml?event=push&label=&branch=main&logo=nodedotjs&logoColor=535c68&color=badc58)](https://github.com/wellwelwel/lru.min/actions/workflows/ci_node.yml?query=branch%3Amain) [![GitHub Workflow Status (Bun)](https://img.shields.io/github/actions/workflow/status/wellwelwel/lru.min/ci_bun.yml?event=push&label=&branch=main&logo=bun&logoColor=ffffff&color=f368e0)](https://github.com/wellwelwel/lru.min/actions/workflows/ci_bun.yml?query=branch%3Amain) [![GitHub Workflow Status (Deno)](https://img.shields.io/github/actions/workflow/status/wellwelwel/lru.min/ci_deno.yml?event=push&label=&branch=main&logo=deno&logoColor=ffffff&color=079992)](https://github.com/wellwelwel/lru.min/actions/workflows/ci_deno.yml?query=branch%3Amain) 🔥 An extremely fast, efficient, and lightweight LRU Cache for JavaScript (Browser compatible).

## Why another LRU? - 🎖️ **lru.min** is fully compatible with both **Node.js** _(8+)_, **Bun**, **Deno** and, browser environments. All of this, while maintaining the same high performance [_(and a little more)_](https://github.com/wellwelwel/lru.min?tab=readme-ov-file#performance) as the most popular **LRU** packages. --- ## Install ```bash # Node.js npm i lru.min ``` ```bash # Bun bun add lru.min ``` ```bash # Deno deno add npm:lru.min ``` --- ## Usage ### Quickstart ```js import { createLRU } from 'lru.min'; const max = 2; const onEviction = (key, value) => { console.log(`Key "${key}" with value "${value}" has been evicted.`); }; const LRU = createLRU({ max, onEviction, }); LRU.set('A', 'My Value'); LRU.set('B', 'Other Value'); LRU.set('C', 'Another Value'); // => Key "A" with value "My Value" has been evicted. LRU.has('B'); LRU.get('B'); LRU.delete('B'); // => Key "B" with value "Other Value" has been evicted. LRU.peek('C'); LRU.clear(); // ← recommended | LRU.evict(max) → (slower alternative) // => Key "C" with value "Another Value" has been evicted. LRU.set('D', "You're amazing 💛"); LRU.size; // 1 LRU.max; // 2 LRU.available; // 1 LRU.resize(10); LRU.size; // 1 LRU.max; // 10 LRU.available; // 9 ``` > For _up-to-date_ documentation, always follow the [**README.md**](https://github.com/wellwelwel/lru.min?tab=readme-ov-file#readme) in the **GitHub** repository. ### Import #### ES Modules ```js import { createLRU } from 'lru.min'; ``` #### CommonJS ```js const { createLRU } = require('lru.min'); ``` #### Browser > Requires **ES6**. ```html ``` - You can use tools such as [**Babel**](https://github.com/babel/babel) to increase the compatibility rate. ### Create a new LRU Cache > Set maximum size when creating **LRU**. ```ts const LRU = createLRU({ max: 150_000 }); ``` Also, you can set a callback for every deletion/eviction: ```ts const LRU = createLRU({ max: 150_000, onEviction: (key, value) => { // do something }, }); ``` ### Set a cache Adds a key-value pair to the cache. Updates the value if the key already exists ```ts LRU.set('key', 'value'); ``` > `undefined` keys will simply be ignored. - Complexity: **O(1)**. ### Get a cache Retrieves the value for a given key and moves the key to the most recent position. ```ts LRU.get('key'); ``` - Complexity: **O(1)**. ### Peek a cache Retrieves the value for a given key without changing its position. ```ts LRU.peek('key'); ``` - Complexity: **O(1)**. ### Check if a key exists ```ts LRU.has('key'); ``` - Complexity: **O(1)**. ### Delete a cache ```ts LRU.delete('key'); ``` - Complexity: **O(1)**. ### Evict from the oldest cache Evicts the specified number of the oldest items from the cache. ```ts LRU.evict(1000); ``` - Complexity: **O(key)** — even if passed a number greater than the number of items, only existing items will be evicted. > [!TIP] > > - Methods that perform eviction(s) when maximum size is reached: `set` and `resize`. > - Methods that always perform eviction(s): `delete`, `clear`, and `evict` itself. ### Resize the cache Resizes the cache to a new maximum size, evicting items if necessary. ```ts LRU.resize(50_000); ``` - Complexity: - Increasing: **O(newMax - max)**. - Downsizing: **O(n)**. ### Clear the cache Clears and disposes (if used) all key-value pairs from the cache. ```ts LRU.clear(); ``` - Complexity: - Without `onEviction`: **O(1)**. - Using `onEviction`: **O(entries)**. ### Debugging #### Get the max size of the cache ```ts LRU.max; ``` - Complexity: **O(1)**. #### Get the current size of the cache ```ts LRU.size; ``` - Complexity: **O(1)**. #### Get the available slots in the cache ```ts LRU.available; ``` - Complexity: **O(1)**. ### Iterating the cache #### Get all keys Iterates over all keys in the cache, from most recent to least recent. ```ts const keys = [...LRU.keys()]; ``` - Complexity: **O(keys)**. #### Get all values Iterates over all values in the cache, from most recent to least recent. ```ts const values = [...LRU.values()]; ``` - Complexity: **O(values)**. #### Get all entries Iterates over `[key, value]` pairs in the cache, from most recent to least recent. ```ts const entries = [...LRU.entries()]; ``` - Complexity: **O(entries)**. #### Run a callback for each entry Iterates over each value-key pair in the cache, from most recent to least recent. ```ts LRU.forEach((value, key) => { // do something }); ``` - Complexity: **O(entries)**. --- > [!NOTE] > > - We use `O(keys)`, `O(values)`, `O(entries)`, and `O(newMax - max)` to explicitly indicate what is being iterated over. In traditional complexity notation, this would be represented as `O(n)`. --- ### TypeScript You can set types for both keys and values. For example: ```ts import { createLRU } from 'lru.min'; type Key = number; type Value = { name: string; }; const LRU = createLRU({ max: 1000 }); LRU.set(1, { name: 'Peter' }); LRU.set(2, { name: 'Mary' }); ``` Also: ```ts import { createLRU, type CacheOptions } from 'lru.min'; type Key = number; type Value = { name: string; }; const options: CacheOptions = { max: 10, onEviction(key, value) { console.log(key, value); }, }; // No need to repeat the type params const LRU = createLRU(options); LRU.set(1, { name: 'Peter' }); LRU.set(2, { name: 'Mary' }); ``` --- ### Performance The benchmark is performed by comparing `1,000,000` runs through a maximum cache limit of `100,000`, getting `333,333` caches and deleting `200,000` keys 10 consecutive times, clearing the cache every run. > - [**lru-cache**](https://github.com/isaacs/node-lru-cache) `v11.0.0` ```sh # Time: lru.min: 240.45ms lru-cache: 258.32ms # CPU: lru.min: 275558.30µs lru-cache: 306858.30µs ``` - See detailed results and how the tests are run and compared in the [**benchmark**](https://github.com/wellwelwel/lru.min/tree/main/benchmark) directory. --- ## Security Policy [![GitHub Workflow Status (with event)](https://img.shields.io/github/actions/workflow/status/wellwelwel/lru.min/ci_codeql.yml?event=push&label=&branch=main&logo=github&logoColor=white&color=f368e0)](https://github.com/wellwelwel/lru.min/actions/workflows/ci_codeql.yml?query=branch%3Amain) Please check the [**SECURITY.md**](https://github.com/wellwelwel/lru.min/blob/main/SECURITY.md). --- ## Contributing See the [**Contributing Guide**](https://github.com/wellwelwel/lru.min/blob/main/CONTRIBUTING.md) and please follow our [**Code of Conduct**](https://github.com/wellwelwel/lru.min/blob/main/CODE_OF_CONDUCT.md) 🚀 --- ## Acknowledgements - [![Contributors](https://img.shields.io/github/contributors/wellwelwel/lru.min?label=Contributors)](https://github.com/wellwelwel/lru.min/graphs/contributors) - **lru.min** is inspired by [**lru-cache**](https://github.com/isaacs/node-lru-cache) architecture and [**quick-lru**](https://github.com/sindresorhus/quick-lru) usage, simplifying and improving their concepts for enhanced performance and compatibility. > [!IMPORTANT] > > No [**lru-cache**](https://github.com/isaacs/node-lru-cache) or [**quick-lru**](https://github.com/sindresorhus/quick-lru) code is used in **lru.min**. For more comprehensive features such as **TTL** support, consider using and supporting them 🤝 --- ## License **lru.min** is under the [**MIT License**](https://github.com/wellwelwel/lru.min/blob/main/LICENSE).
Copyright © 2024-present [Weslley Araújo](https://github.com/wellwelwel) and **lru.min** [contributors](https://github.com/wellwelwel/lru.min/graphs/contributors).