This is a take home assignment for T.

Overview

This API backend provides the following endpoints:

POST /v1/users

Adds a user to the database. The request body should include an email field, as shown in the example below:

{
  "email": "[email protected]"
}

GET /v1/users

Retrieves a list of users with pagination capabilities. This endpoint accepts the following query string parameters:

• searchStr: The search string used to filter users (by email column) to return.
• pageSize: The number of users returned per page. Defaults to 10, with a maximum of 100.
• cursor: The pagination cursor, which must be provided to retrieve the next page of users.

GET /v1/health

A health check endpoint to verify the API's status.

Development

Tech stack:

• Node.js 22+
• Typescript
• Fastify
• Drizzle
• Postgres
• Vitest

Environmental Variables

The .env.dev file must contain the following environmental variables to configure the application:

HOST

Specifies the host IP address that will serve the API.

PORT

Specifies the port on which the app will serve the API. Setting PORT=0 will automatically choose a random available port.

CORS

Specifies the CORS policy for the API. This can be set to:

• CORS=https://somedomain.com to allow requests from a specific domain.
• CORS=https://somedomain.com https://anotherdomain.com to allow requests from multiple domains.
• CORS=* to allow requests from any domain.

DB_URL

The connection string to a Postgres database.

Run from source locally

Start the local Postgres DB.

docker run -d \
  --name test-db \
  -e POSTGRES_USER=postgres \
  -e POSTGRES_PASSWORD=postgres \
  -e POSTGRES_DB=myapp_test \
  -p 5432:5432 \
  postgres:15-alpine

Run server

npm run start:dev

Run in a container locally

Build the image

docker build -t t_takehome .

Run container (this will start both a dockerized Postgres instance and the image built in previous step)

docker-compose up -d

Testing

The code has 100% code coverage as it is supposed to be mission-critical.
Unit tests cover basic functionality and use mock database instead of a real Postgres, while integration tests work with a real PostgresDB to test parts of code that read/write to DB.

npm run test:unit - runs unit tests
npm run test:integration - starts test DB, runs integration tests, stops test DB
npm run coverage - generates a coverage report (for both unit and integration tests)
npm run load-test - with DB and server running runs a basic load test with artillery (Note: these are mostly boilerplate, proper load test would require cloud staging environment to draw meaningful conclusions)