Finish remaining code

README.md

@@ -1,12 +1,82 @@
 # jss-devsecops-challenge
 
-This is a practical test for a DevSecOps Engineer candidate at Bank J. Safra Sarasin. Instructions received (on 09.02.2025) from the recruiter are attached to this repo.
+DevSecOps assessment - device registration and statistics API built with Python (Flask) and MariaDB.
 
-### On 09.02.2026
-I created repo on https://git.harshanu.space. I'll work on code changes tomorrow as I will be free in the afternoon (Fashing Tuesday, half day work)
+## What it does
 
-### On 10.02.2026
-- Defined the database schema for the API endpoints in `init.sql`.
-- Pulled the `docker.io/library/mariadb:12` Docker image.
-- Tested the schema by spinning up a MariaDB container and verifying the table creation.
-- Python will be used to write API endpoints
+A single API server that tracks device type registrations per user. It exposes three endpoints:
+
+- `POST /log/auth` - logs a user login event by storing the device type
+- `GET /log/auth/statistics?deviceType=iOS` - returns count of registrations for a given device type
+- `POST /device/register` - directly registers a device type for a user
+
+Accepted device types: iOS, Android, Watch, TV, Tablet, Desktop, IoT.
+In contrast to API endpoints asked in pdf file, I used smaller case here.
+
+## Project structure
+
+```
+app/server.py           - Flask application with all endpoints
+tests/test_app.py       - unit tests (mocked DB)
+init.sql                - MariaDB schema initialization
+Dockerfile              - container image for the API
+docker-compose.yml      - full stack (MariaDB + API)
+requirements.txt        - Python dependencies
+```
+
+## Docker Hub
+
+The API image is published to Docker Hub:
+
+```
+docker.io/harshavmb/jss-devsecops-api:latest
+```
+
+To pull it directly:
+
+```bash
+docker pull harshavmb/jss-devsecops-api:latest
+```
+
+MariaDB is used from the official registry (`docker.io/library/mariadb:12`) and does not need a custom image. The schema is applied at startup via the init SQL script mounted in docker-compose.
+
+## Running locally with Docker Compose
+
+```bash
+docker compose up --build -d
+```
+
+This starts MariaDB, runs the init SQL script, and launches the API on port 5000.
+
+To stop:
+
+```bash
+docker compose down -v
+```
+
+## Running tests
+
+```bash
+pip install -r requirements.txt
+pytest tests/ -v
+```
+
+## Security controls
+
+- Input validation on userKey (regex whitelist) and deviceType (enum whitelist)
+- Parameterized SQL queries to prevent injection
+- Rate limiting (30 req/min per endpoint, 60 req/min global)
+- Non-root container user
+- No secrets hardcoded (configurable via DATABASE_URL env var)
+- No docker/podman container is run as root user (that depends on how docker/podman are configured on host)
+- Authentication of endpoints is left out for brevity
+
+## Configuration
+
+The API reads `DATABASE_URL` from the environment. Format:
+
+```
+mysql://user:password@host:port/database
+```
+
+Default: `mysql://root:my-secret-pw@localhost:3306/devsecops_db`