cache-list v0.1.9

Cache List

Install

$ npm install cache-list

How to use

import { MemoryCache } from 'cache-list';

const cache = new MemoryCache({
    defaultDuration: 600, // 10 min
});

const data = [
    {
        name: 'Tom',
        age: 35
    },
    {
        name: 'Emma',
        age: 29
    }
];

cache.set('users', data, 3600); // 60 min

if (cache.exists('users')) {
    return cache.get('users');
}

List:

• MemoryCache
• RedisCache

Properties

• defaultDuration integer - Default duration in seconds before a cache entry will expire.
• keyPrefix string - A string prefixed to every cache key so that it is unique globally in the whole cache storage.
• serialization boolean - Store serialized or unserialized cached data.

Methods

• buildKey - Builds a normalized cache key from a given key.
• exists - Checks whether a specified key exists in the cache.
• get - Retrieves a value from cache with a specified key.
• multiGet - Retrieves multiple values from cache with the specified keys.
• set - Stores a value identified by a key into cache.
• multiSet - Stores multiple items in cache. Each item contains a value identified by a key.
• add - Stores a value identified by a key into cache if the cache does not contain this key.
• multiAdd - Stores multiple items in cache. Each item contains a value identified by a key.
• delete - Deletes a value with the specified key from cache.
• flush - Deletes all values from cache.

Property Details

defaultDuration

Default duration in seconds before a cache entry will expire. Default value is 0, meaning infinity. This value is used by set() if the duration is not explicitly given.

keyPrefix

A string prefixed to every cache key so that it is unique globally in the whole cache storage. It is recommended that you set a unique cache key prefix for each application if the same cache storage is being used by different applications.

To ensure interoperability, only alphanumeric characters should be used.

serialization

If this property is set false, data will be directly sent to and retrieved from the cache component without any serialization or deserialization.

Method Details

buildKey

Builds a normalized cache key from a given key.

If the given key is a string containing alphanumeric characters only and no more than 32 characters, then the key will be returned back prefixed with keyPrefix. Otherwise, a normalized key is generated by serializing the given key, applying MD5 hashing, and prefixing with keyPrefix.

exists

Checks whether a specified key exists in the cache.

This can be faster than getting the value from the cache if the data is big.

get

Retrieves a value from cache with a specified key.

multiGet

Retrieves multiple values from cache with the specified keys.

Some caches allow retrieving multiple cached values at the same time, which may improve the performance. In case a cache does not support this feature natively, this method will try to simulate it.

set

Stores a value identified by a key into cache.

If the cache already contains such a key, the existing value and expiration time will be replaced with the new ones, respectively.

multiSet

Stores multiple items in cache. Each item contains a value identified by a key.

If the cache already contains such a key, the existing value and expiration time will be replaced with the new ones, respectively.

add

Stores a value identified by a key into cache if the cache does not contain this key.

Nothing will be done if the cache already contains the key.

multiAdd

Stores multiple items in cache. Each item contains a value identified by a key.

If the cache already contains such a key, the existing value and expiration time will be preserved.

delete

Deletes a value with the specified key from cache.

flush

Deletes all values from cache.

Be careful of performing this operation if the cache is shared among multiple applications.

MemoryCache

Use memory as a storage.

RedisCache

Use Redis as a storage.

Properties

• isSharedDatabase boolean - If you use a separated database to store a cache, set keyPrefix
• clientOptions object - Config for redis connections. You can find a full list of redis client options here.

const cache = new RedisCache();

const cache = new RedisCache({
    clientOptions: {
        db: 2
    }
});

const cache = new RedisCache(
    {
        isSharedDatabase: true,
        keyPrefix: 'active_users',
        clientOptions: {
            db: 1
        }
    }
);

Redis Client Options