Key Value Data-Store

This is a file based Key value data store built using node js

Core Functionalities

1. Supports CREATE , READ , DELETE and UPDATE operation
2. Restricts key size to 32 chars and value size to 16KB
3. Allows client to instantiate the class and work on
4. File can be created using optional file path , if it is not provided it will be created in current working directory
5. Allows only one client to access file at a time
6. Every key will have a optional timeToLive property
7. Uses Singleton approach
8. Thread safe

Steps to run file locally:

1. run npm i to install dependencies
2. run npm start to run the application [ This will run the sample client file provided in the repo ]
3. run npm test to run tests

Usage

Import the data store

let dataStore = require("./src/dataStore")    

Creating an instance for the dataStore
This takes two arguments clientId and file path(optional)
note: clientId is a four digit number provided by user, it restricts the file access to only one client process at any given time in a computer

let clientId = 2343; //sample clientId
let myDataStore = new dataStore(clientId);
let instance = myDataStore.getInstance()   

Create operation

let key = "person1";
let value = { age: 22, userId: 2345, city: "chennai" };
let timeToLive = 3;
instance.create(key, value, timeToLive);

Read operation

let myValue = instance.get("person1");    

Delete operation

instance.delete("person1");   

Update operation

let newValue = { age: 24, userId: 2345, city: "pune" };
instance.update("person1", newValue);