sambr7/s2i-python-container

Python container images based on Red Hat Software Collections and intended for OpenShift and general usage, that provide a platform for building and running Python applications. Users can choose between Red Hat Enterprise Linux, Fedora, and CentOS based images.

Python container images

This repository contains the source for building various versions of the Python application as a reproducible container image using source-to-image. Users can choose between RHEL, Fedora and CentOS based builder images. The resulting image can be run using podman or docker.

For more information about using these images with OpenShift, please see the official OpenShift Documentation.

For more information about concepts used in these container images, see the Landing page.

Contributing

In this repository distgen > 1.0 is used for generating directories for Python versions. Also make sure distgen imports the jinja2 package >= 2.10.

Files in directories for a specific Python version are generated from templates in the src directory with values from specs/multispec.yml.

A typical way how to contribute is:

1. Add a feature or fix a bug in templates (src directory) or values (specs/multispec.yml file).
2. Commit the changes.
3. Regenerate all files via make generate-all.
4. Commit generated files.
5. Test changes via make test TARGET=fedora VERSIONS=3.7 which will build, tag and test an image in one step.
6. Open a pull request!

For more information about contributing, see the Contribution Guidelines.

Versions

Python versions currently provided are:

• python-2.7
• python-3.6
• python-3.7
• python-3.8

RHEL versions currently supported are:

• RHEL7

CentOS versions currently supported are:

• CentOS7

Installation

To build a Python image, choose either the CentOS or RHEL based image:

• RHEL based image

  These images are available in the Red Hat Container Catalog. To download it run:

  $ podman pull registry.access.redhat.com/rhscl/python-36-rhel7
  

  To build a RHEL based Python image, you need to run the build on a properly subscribed RHEL machine.

  $ git clone https://github.com/sclorg/s2i-python-container.git
  $ cd s2i-python-container
  $ make build TARGET=rhel7 VERSIONS=3.6
  

• CentOS based image

  This image is available on DockerHub. To download it run:

  $ podman pull centos/python-36-centos7
  

  To build a Python image from scratch run:

  $ git clone https://github.com/sclorg/s2i-python-container.git
  $ cd s2i-python-container
  $ make build TARGET=centos7 VERSIONS=3.6
  

Note: while the installation steps are calling podman, you can replace any such calls by docker with the same arguments.

Notice: By omitting the VERSIONS parameter, the build/test action will be performed on all provided versions of Python.

Usage

For information about usage of Dockerfile for Python 2.7, see usage documentation.

For information about usage of Dockerfile for Python 3.6, see usage documentation.

Test

This repository also provides a S2I test framework, which launches tests to check functionality of a simple Python application built on top of the s2i-python-container image.

Users can choose between testing a Python test application based on a RHEL or CentOS image.

• RHEL based image

  To test a RHEL7-based Python image, you need to run the test on a properly subscribed RHEL machine.

  $ cd s2i-python-container
  $ make test TARGET=rhel7 VERSIONS=3.6
  

• CentOS based image

  $ cd s2i-python-container
  $ make test TARGET=centos7 VERSIONS=3.6
  

Notice: By omitting the VERSIONS parameter, the build/test action will be performed on all provided versions of Python.

Repository organization

• <python-version>

  • Dockerfile

    CentOS based Dockerfile.

  • Dockerfile.rhel7

    RHEL based Dockerfile. In order to perform build or test actions on this Dockerfile you need to run the action on a properly subscribed RHEL machine.

  • s2i/bin/

    This folder contains scripts that are run by S2I:

    • assemble

      Used to install the sources into the location where the application will be run and prepare the application for deployment (eg. installing dependencies, etc.)

    • run

      This script is responsible for running the application by using the application web server.

    • usage*

      This script prints the usage of this image.

  • contrib/

    This folder contains a file with commonly used modules.

  • test/

    This folder contains a S2I test framework with a simple server.

    • setup-test-app/

      Simple Gunicorn application used for testing purposes by the S2I test framework.

    • standalone-test-app/

      Simple standalone application used for testing purposes by the S2I test framework.

    • run

      Script that runs the S2I test framework.