docker-alpine-python-flask

This Dockerfile creates a simple container for running Python and Flask using the latest Alpine base, and copies a flask-website.py file into the working directory. The python script enables simple access for http header info, IP addressing and environment variables for testing load balancing, container failure, and orchestration.

Usage

Build the container image from current directory and publish to docker hub.
Replace the user and image names as needed for your setup.

1. docker build -t mutineer612/flask-website .
2. docker push mutineer612/flask-website

• The Dockerfile does not expose a specific port enabling change without rebuilding the container.

Run the container locally passing the MY_PORT environment variable to the flask-website.py script. With MacOS and Windows need to use the -p switch and map the port to the container. With Linux you can optionally use the 'host' network driver.

• docker run -e MY_PORT=8888 -p 8888:8888 --rm --name flask mutineer612/flask-website

• By running the container and remaining attached to the console you can see the http requests/responses

Site Navigation

The flask-website.py script creates the following URL's

1. / Displays 'Hello World! Running on container ID: {hostname}'
2. /health-check Is an empty directory that returns HTTP_204 to satisfy load balancing health checks
3. /headers Returns http header content showing client IP, browser, and OS
4. /ips Returns a list of container and host IP addresses by interface
5. /env Returns a list of the containers environment variables
6. /stop Executes a function call to shutdown the Werkzeug Server (i.e. Flask Development Web Server)

• Navigating to /stop will stop the container. This is a function of the built in dev Flask web server.

Based on original work located here: https://github.com/yafernandes