redis-json

redis-json

Nodejs library to store/retreive JSON Objects in RedisDB

Description

Every time set is called JSON object is flattened(embeded objects are converted to path keys) and then stored in Redis just like a normal hashset, on get the hashset is unflattened and converted back to the original JSON object.
Under the hood it uses flat library for flattening and unflattening JSON objects

Installation

npm i redis-json -D

Usage

const Redis = require('ioredis');
const redis = new Redis();

const JSONCache = require('redis-json');

const jsonCache = new JSONCache(redis, {prefix: 'cache:'});

const user = {
  name: 'redis-json',
  age: 25,
  address: {
    doorNo: '12B',
    locality: 'pentagon',
    pincode: 123456
  },
  cars: ['BMW 520i', 'Audo A8']
}

await jsonCache.set('123', user)

const response = await jsonCache.get('123')
console.log(response)
// output
// {
//   name: 'redis-json',
//   age: 25,
//   address: {
//     doorNo: '12B',
//     locality: 'pentagon',
//     pincode: 123456
//   },
//   cars: ['BMW 520i', 'Audo A8']
// }

API

Constructor

JSONCache(redisClient, options)

redisClient: RedisClient instance(Preferred ioredis - cient). It support any redisClient instance that has keys, multi, set, get & del methods implemented

options.prefix: Prefix for redis keys. Defaults to jc: (jsonCache)

Methods

set(key, jsobObject, options): <Promise>

key: The redis key that the JSON object has to be stored against.
jsonObject: JSON obejct that needs to be stored.
options.expire: Max time-to-live before key expiry

if the key already exists, and is of type hashset, then the field in JSON object will get updated along with the existing data.

get(key) <Promise>

key: The redis key in which the JSON object was stored.

Note: if the key is not of type hashset, then redis will through error.

resave rewrite(key, jsonObj): <Promise>

key: The redis key that whose value needs to be replaced with the new one. jsonObject: JSON obejct that needs to be stored.

Even if key is not of type hashset, resave rewrite will delete it and update the JSON object in the provided key.

clearAll(): <Promise>

Clears/removes all the keys with the prefix from redis using multi command.
Useful when trying to refresh the entire cache.

Mocha & Chai (Testing)

npm test

Coverage Report

npm run coverage

Contributions

This is open-source, which makes it obvious for any PRs, but I would request you to add necessary test-cases for the same

LICENCE

MIT License