aws-serverless

A TypeScript AWS Lambda service backed by MongoDB Atlas, with a GitHub Actions pipeline for CI and deployment. It was originally built as the backend authentication service for Find My Roommates, a roommate-matching web product. It is kept here as a code sample.

What it does

The Lambda handler (src/index.ts) implements user registration and login:

• POST /registration — validates input with Joi, checks for an existing user in MongoDB, sends a confirmation email via SendGrid, and hashes the password with bcrypt before storing the new user.
• POST /login — verifies credentials and issues a JWT access token.

Tech stack

• TypeScript
• AWS Lambda (Node.js 18)
• MongoDB Atlas (mongodb driver)
• SendGrid (@sendgrid/mail) for transactional email
• Joi for request validation
• bcryptjs for password hashing
• jsonwebtoken for auth tokens
• Gulp for the build (TypeScript compile + asset copy)
• GitHub Actions for CI and deployment to AWS Lambda via S3

Project structure

src/
  index.ts             # Lambda handler: registration and login routes
  sendgrid.service.ts  # Sends confirmation emails via SendGrid
  crypto.service.ts    # Password hashing and comparison (bcrypt)
  helper.ts            # writeLog — structured console logging with a request hash
.github/workflows/
  ci.yml               # Runs npm ci + build on pull requests
  main.yml             # Builds, zips, and deploys to Lambda via S3 on push to main
gulpfile.js            # Build pipeline: clean -> compile -> copy deps -> copy env files

Running locally

nvm use          # Node 18.17.1, see .nvmrc
npm install
cp .env.example .env   # fill in real values, see table below
npm run build     # compiles src/ to dist/ with gulp

There is no local HTTP server here. The dist/ build output is what the GitHub Actions workflow zips and uploads to AWS Lambda; to exercise the handler locally, invoke handler from dist/index.js with a mock event.

Environment variables

Variable	Description
MONGO_DB_PASSWORD	Password for the roommates MongoDB Atlas user
SENDGRID_API_KEY	API key used to send confirmation emails via SendGrid
DOMAIN	Base URL used to build the email confirmation link
PASSPORT_SECRET	Secret used to sign JWT access tokens on login

In CI, these are injected from GitHub Actions secrets (main.yml).

Status

Find My Roommates is no longer in production. This repository is preserved as a code sample and is not actively deployed.