KeyvNest

KeyvNest is a hierarchical caching adapter for the Keyv module. It allows you to nest multiple caching layers, such as memory cache, disk cache, and network cache, to create a multi-layered caching mechanism.

Table of Contents

• Installation
• Usage
• API
• Examples
• Contributing
• License

Installation

You can install the module via npm:

npm install keyv-nest

Usage

First, import the module and create instances of your cache stores. Then, use KeyvNest to create a hierarchical caching structure.

import Keyv from 'keyv';
import KeyvNest from 'keyv-nest';

const memoryCache = new Keyv({ store: new Map() });
const diskCache = new Keyv({ store: new KeyvFileStore('/path/to/store') });
const networkCache = new Keyv({ store: new SomeNetworkStore() });

const nestedCache = KeyvNest(memoryCache, diskCache, networkCache);

(async () => {
  await nestedCache.set('foo', 'bar');
  const value = await nestedCache.get('foo');
  console.log(value); // 'bar'
})();

API

KeyvNest

KeyvNest(cache: KeyvStore<T>, store: KeyvStore<T>, ...rest: KeyvStore<T>[]): KeyvStore<T>

Creates a nested cache adapter that allows for multi-layered caching.

• cache: The primary cache store (usually memory cache).
• store: The secondary cache store (usually disk cache).
• rest: Additional cache stores (e.g., network cache).

Returns a KeyvStore instance with the following methods:

get(key: string): Promise<T>

Retrieves a value from the cache hierarchy. If the value is found in the primary cache, it is returned. Otherwise, it checks the secondary cache and so on. If a value is found in any cache layer, it is promoted to the primary cache.

• key: The cache key.
• returns: A promise that resolves to the cached value or undefined.

set(key: string, value: T, ...rest: any[]): Promise<any>

Sets a value in all layers of the cache hierarchy.

• key: The cache key.
• value: The value to cache.
• ...rest: Additional arguments for cache store set operations.
• returns: A promise that resolves when the operation has completed.

delete(key: string): Promise<any>

Deletes a value from all layers of the cache hierarchy.

• key: The cache key.
• returns: A promise that resolves when the operation has completed.

clear(): Promise<any>

Clears all values from all layers of the cache hierarchy.

• returns: A promise that resolves when the operation has completed.

Examples

Here is an example of using KeyvNest with memory and disk caches:

import Keyv from 'keyv';
import KeyvNest from 'keyv-nest';

const memoryCache = new Keyv({ store: new Map() });
const diskCache = new Keyv({ store: new KeyvFileStore('/path/to/store') });

const nestedCache = KeyvNest(memoryCache, diskCache);

(async () => {
  await nestedCache.set('username', 'john_doe');
  const username = await nestedCache.get('username');
  console.log(username); // 'john_doe'

  await nestedCache.delete('username');
  const deletedUsername = await nestedCache.get('username');
  console.log(deletedUsername); // undefined

  await nestedCache.clear();
})();

Contributing

Contributions are welcome! Please open an issue or submit a pull request for any feature requests, bug reports, or improvements.

License

This module is open-source and licensed under the MIT License. For more details, see the LICENSE file.