nQueensChallenge

This project resolves the eight queens puzzle: problem description.
It uses a Postgres db to store the results wrapped by SqlAlchemy API, tested via pytest module and some plugins for db fixtures and mocking. Also it it uses Travis for CI, alembic for migrations and all the solution is dockerized within docker compose.

Prerequisites

You can run only the sollution algorithm with python3 or install as a whole with docker-compose

pytest, sqlalchemy, psycopg2

Installation

I strongly recomend to use a virtual enviroment to install the

git clone https://github.com/allanstone/nQueensChallenge.git .
pip install -r requirements.txt #run as standalone script without db
python main.py <number-of-queens>

Installation with Docker

git clone https://github.com/allanstone/nQueensChallenge.git
cd nQueensChallenge/
docker-compose up -d
docker logs #results should be there!

Database

The database url is configured on config.py it can be easily changed for production or another db

DATABASE_URI = 'postgres+psycopg2://postgres:post123@localhost:5432/testdb'

Migrations

Project uses alembic to manage migrations script http://alembic.zzzcomputing.com/en/latest/

Example usage

Add new migrations with

alembic revision --autogenerate -m "migration name"

Upgrade your database with

alembic upgrade head

Tests

Running the tests, using diferent flags from the fixtures, aviod warning due 'postgres' dialect name has been renamed to 'postgresql'

py.test  nQueensChallenge/tests/ --sqlalchemy-connect-url="postgres+psycopg2://postgres:post123@localhost:5432/testdb" -p no:warnings -v
py.test --sqlalchemy-config-file nQueensChallenge/tests/test_db.py  -p no:warnings -v
py.test  nQueensChallenge/tests/test_db.py  -p no:warnings -v

Optimizations

Add code coverage with coveralls or codecov
Use a tool like tox-travis to test diferent python versions
Deploy a more consistent architecture for microservices (e.g using kubernetes or docker swarm)

matin/nQueensChallenge