Ventnurenox Associate Backend Engineer Hiring Test

Overview:

The aim of this assessment is to evaluate your backend skills using NodeJS and by adopting a microservice architecture. The assessment will primarily be a web app where you'll be exposing API endpoints, interacting with Database via ORM, producing and consuming event via Kafka.

Suggested Techstack:

• NodeJS

• ExpressJS (web server)

• Objection JS (ORM)

• KnexJS (Query Builder)

• KafkaJS

Note: you may use whichever ORM or Qerybuilder you arer comfortable with.

Assissting Technology (provided in the starter code)

• Docker Compose file for orchestrating multiple services

• Postgres

• Adminer

• Kafka

Assessment:

For this assessment you will be using the following ERD. The following have 2 major tables having a single one to many relationship between them.

Task 0: Running the repo

The repo has been created in a microservice fashion using docker and docker compose. In order to run the whole repo use the following command to run all the services/containers:

docker-compose up -d --build

To stop all containers use the following command:

docker-compose down

To run a specific microservice:

docker-compose up -d --build <servicename>

Note: For every change that you make in the code, in order to rerflect those you need to re-run the container using the first command given in this section.

If you dont have docker and docker-compose setup in your system consult the following:

For Debain based linux distros:

Install docker and docker-compose using the following command in terminal:

sudo apt install docker docker-compose

For windows systems:

Install docker desktop.

For other OS:

Consult the installation guide relevant to your system on the Docker offical website.

NOTE: A service named social has already been setup with kafka for you to work in. Start working in ./backend/social/

Task 1: Checking the Sample web server code

Study the starter code for the web service provided. In which a sample web server has been created for you with a sample router/endpoint in it. You are to run the endpoint successfully via browser or Postman to check if you able to run the web app successfully.

Task 2: Creating the database using ORM/Query builder

Using the ERD provided above create the database using an ORM/Query builder. Throughout this assessment you are required to use only the ORM/Query builder to interact with the database and the tables inside of it. Add this code to the web server started code provided.

Postgres Credentials

Postgres credentials are provided via enviornment variables.

- host:- process.env.POSTGRES_HOST
- username:- process.env.POSTGRES_USERNAME
- password:- process.env.POSTGRES_PASSWORD
- database:- process.env.POSTGRES_DATABASE 

Task 3: Adding routes/endpoints

For the tables in the database you are to create separate API group(s). In each API group you will have the following category of endpoint with the described funcitonality:

• POST - add data to the corresponding database table, data has to be passed as a raw request in JSON.
• GET - get all data from the corresponding database table
• GET - get specific record based on the ID of the record, this ID has to be passed as a path parameter when requesting the route/endpoint.
• DELETE - delete specific rercord for the correspinding database table, this ID has to be passed as a path parameter when requestion the route/endpoint.
• PATCH - alter a specific record specified by ID in the corresponding database table, this ID has to be passed as a path parameter when requesting the route/endpoint.

Task 4: Implementing Kafka consumer

Social service contains a file StreamManager.js file. This file outputs the consumed data.

For this task a Kafka server has already been setup and utility classes have been provided in order to seamlessly connect and communicate with the topics. You are to use this provided code of a consumer in order to consume messages from the a specific topic (specified in Kafka utility code), parse them and insert the consumed messaged in appropriate database tables.