BlockFlix

This is a Flask application that implements an DVD Rental company's online transaction processing (OLTP) application. This application implements a database schema similar to loosely modeled after MySQL's Sakila sample database.

This project is designed to be used in a Full Stack Data Engineering course. There is no real front end functionality beyond a few data tables. Use this application for practicing seeding data, deploying applications, and performing ETL operations.

Running with Docker

Build the Docker image for Blockflix:

docker build -t blockflix .

Run the application and database with Docker Compose:

docker-compose up

Access the applicaiton on port 5000:

http://localhost:5000

Development Setup

Follow these instructions to install the application on your computer.

Install OS Dependencies

Install these OS dependencies:

• MySQL
• Python 3
• Nodejs

Application Installation

Download the application codebase, install the Python packages and Node.js packages:

git clone https://github.com/mikeghen/blockflix
cd blockflix
pip install -r requirements/dev.txt
npm install

Set the following Flask environment variables before running the application:

export FLASK_APP=autoapp.py
export FLASK_DEBUG=1

Database Setup

Start by creating the application's database on your MySQL database server and database user:

CREATE DATABASE blockflix_development;
CREATE USER 'blockflix'@'127.0.0.1' IDENTIFIED BY 'blockflix';
GRANT ALL PRIVILEGES ON blockflix_development.* TO 'blockflix'@'localhost';

Run the following to create database tables for the application:

flask db upgrade

Start the Application

Finally, run the development server with:

npm start

Deployment

To deploy:

export FLASK_DEBUG=0
npm run build   # build assets with webpack
flask run       # start the flask server

In your production environment, make sure the FLASK_DEBUG environment variable is unset or is set to 0, so that ProdConfig is used.

ℹ️ We will use Elastic Beanstalk to deploy the application.

Shell

To open the interactive shell, run ::

flask shell

By default, you will have access to the flask app.

Running Tests

To run all tests, run:

flask test

Migrations

Whenever a database migration needs to be made. Run the following commands ::

flask db migrate

This will generate a new migration script. Then run ::

flask db upgrade

To apply the migration.

For a full migration command reference, run flask db --help.

Asset Management

Files placed inside the assets directory and its subdirectories (excluding js and css) will be copied by webpack's file-loader into the static/build directory, with hashes of their contents appended to their names. For instance, if you have the file assets/img/favicon.ico, this will get copied into something like static/build/img/favicon.fec40b1d14528bf9179da3b6b78079ad.ico. You can then put this line into your header::

<link rel="shortcut icon" href="{{asset_url_for('img/favicon.ico') }}">

to refer to it inside your HTML page. If all of your static files are managed this way, then their filenames will change whenever their contents do, and you can ask Flask to tell web browsers that they should cache all your assets forever by including the following line in your settings.py::

SEND_FILE_MAX_AGE_DEFAULT = 31556926  # one year