Cache Library

A simple caching library for TypeScript that provides a decorator for caching method results.

Installation

To install the cache library, use npm:

npm i @tyagoveras/cache-library

Usage

Importing the Library

You can import the library in your TypeScript project as follows:

import { cacheInjectable, CacheInvalidate } from '@tyagoveras/cache-library';

Using the Cache Decorator

You can use the cacheInjectable decorator to cache the results of class methods. Here’s an example:

class ExampleService {
  @cacheInjectable({ cacheKey: 'exampleMethod', ttl: 5000 })
  exampleMethod() {
    console.log('Executing exampleMethod');
    return 'result';
  }
}

Parameters

• cacheKey: A unique key for the cached result.
• ttl: Time-to-live for the cached result in milliseconds.

Configuration file cache-config.json

The library uses a configuration file named cache-config.json to manage cache settings. The file should be placed in the root directory of your project.

{
  "strategy": "node-cache | redis",
  "connectionUrl": "redis://localhost:6379",
  "defaultRootKey": "app",
  "defaultTtl": 60000
}

• strategy: The caching strategy to use. Options are node-cache or redis.

cacheInjectable(options: { cacheKey: string; ttl: number })

This decorator can be applied to any class method to enable caching.

CacheInvalidate(options: CacheInvalidateOptions)

This decorator invalidates cache entries after the method executes successfully. Useful for clearing cache when data is updated or deleted.

Options

• cacheKeys: Array of cache keys to invalidate (uses the same key format as cacheInjectable)
• patterns: Array of patterns to match multiple cache keys (supports wildcards with *)
• invalidateAll: Boolean to invalidate all cache entries with the default root key

Examples

class UserService {
  @cacheInjectable({ cacheKey: 'getUser', ttl: 60000 })
  async getUser(userId: string) {
    console.log('Fetching user from database');
    return { id: userId, name: 'John Doe' };
  }

  @CacheInvalidate({ cacheKeys: ['getUser'] })
  async updateUser(userId: string, data: any) {
    console.log('Updating user in database');
    // Update logic here
    return { id: userId, ...data };
  }

  @CacheInvalidate({ patterns: ['getUser*', 'listUsers*'] })
  async deleteUser(userId: string) {
    console.log('Deleting user from database');
    // Delete logic here
  }

  @CacheInvalidate({ invalidateAll: true })
  async resetAllUsers() {
    console.log('Resetting all users');
    // Reset logic here
  }
}

Contributing

Feel free to submit issues or pull requests to improve the library.

License

This project is licensed under the MIT License.