docker-alpine-python

Docker containers for running Python applications, based on Alpine Linux with s6 for process management. The goal is to provide small and reliable containers to run Python applications (e.g. Flask web apps).

The containers are based on the alpine-base containers from smebberson/docker-alpine. The alpine-base containers provides highly configurable Docker images running Alpine Linux and s6 process management.

Features

This image features:

Supported Tags

2.7 (Dockerfile)
2.7-onbuild (Dockerfile)
3.5 (Dockerfile)
3.5-onbuild (Dockerfile)

Note

The onbuild images are running pip install -r requirements.txt during the build. This ensures that the dependencies are cached during the build. In order to make this work ensure that your requirements.txt file are in the same directory.

Goals

Provide small Docker images for Python applications
The containers should be highly and simple configurable
Usage of s6-supervise as a simple and reliable process manager

Usage

By default, this container doesn't actually do anything other than provide the building blocks for a Docker container that includes Python.

If you want to run a Python application, you can specify your own command:

docker run -rm -it -v "$(pwd)":/app -w /app sruml/alpine-python:2.7 python app.py

Custom Dockerfile

In most cases you will extend this Docker image in order to run your own application.

To use this image include sruml/alpine-python:2.7 at the top of your Dockerfile.

Inheriting from sruml/alpine-python:2.7 provides you with the ability to easily start your Python application using s6. You have two options for process management:

s6 can keep it running for you, restarting it when it crashes.
The entire container can exit allowing the host machine to kick in and restart it.

See docker-alpine for more information.

The following example shows how to run a simple web application (e.g. Flask app) with the later option:

FROM sruml/alpine-python:2.7-onbuild

# Expose the port for the Flask app
EXPOSE 5000

# Run the Flask app
CMD ["python", "flask_app.py"]

Build your image:

docker build -i sruml/webapp .

Mount your application folder into the container and run it:

docker run -rm -v "$(pwd)":/app -w /app -p 5000:5000 sruml/webapp

Use s6 for automatic restarts

You can also run your Python application as a service with the help of the s6 process manager. In this case the application gets automatically restarted if it exits.

In order to use s6-supervise to manage your application you need to create a run file and put it into the /etc/services.d directory.

Create a folder /etc/services.d/app
Create a file called run in this folder and make it executable
This file starts your Python application

#!/usr/bin/with-contenv sh

# cd into our directory
cd /app

# start your Python application
python app.py

FROM sruml/alpine-python:2.7-onbuild

# Add your application
ADD . /app

# Expose the port for the Flask app
EXPOSE 5000

Examples

See the examples for more usage examples.

License

The code in this repository, unless otherwise noted, is MIT licensed. See the LICENSE file in this repository.

hypebeast/docker-alpine-python