Python for OpenShift - Docker images

This repository contains sources of the images for building various versions of Python applications as reproducible Docker images using source-to-image. User can choose between RHEL and CentOS based builder images. The resulting image can be run using Docker.

Versions

Python versions currently provided are:

• python-3.3

RHEL versions currently supported are:

• RHEL7

CentOS versions currently supported are:

• CentOS7

Installation

To build Python image, choose between CentOS or RHEL based image:

• RHEL based image

  To build a rhel-based python-3.3 image, you need to run the build on a properly subscribed RHEL machine.

  $ git clone https://github.com/openshift/sti-python.git
  $ cd sti-python
  $ make build TARGET=rhel7 VERSION=3.3
  

• CentOS based image

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

  $ docker pull openshift/python-33-centos7
  

  To build Python image from scratch use:

  $ git clone https://github.com/openshift/sti-python.git
  $ cd sti-python
  $ make build VERSION=3.3
  

Notice: By omitting the VERSION parameter, the build/test action will be performed on all provided versions of Python. Since we are now providing only version 3.3, you can omit this parameter.

Usage

To build a simple python-sample-app application, using standalone STI and then run the resulting image with Docker execute:

• For RHEL based image

  $ sti build https://github.com/openshift/sti-python.git --context-dir=3.3/test/setup-test-app/ openshift/python-33-rhel7 python-sample-app
  $ docker run -p 8080:8080 python-sample-app
  

• For CentOS based image

  $ sti build https://github.com/openshift/sti-python.git --context-dir=3.3/test/setup-test-app/ openshift/python-33-centos7 python-sample-app
  $ docker run -p 8080:8080 python-sample-app
  

Accessing the application:

$ curl 127.0.0.1:8080

Test

This repository also provides STI test framework, which launches tests to check functionality of a simple python application built on top of sti-python image.

User can choose between testing python test application based on RHEL or CentOS image.

• RHEL based image

  To test a rhel7-based python-3.3 image, you need to run the test on a properly subscribed RHEL machine.

  $ cd sti-python
  $ make test TARGET=rhel7 VERSION=3.3
  

• CentOS based image

  $ cd sti-python
  $ make test VERSION=3.3
  

Notice: By omitting the VERSION parameter, the build/test action will be performed on all provided versions of Python. Since we are now providing only version 3.3 you can omit this parameter.

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.

  • .sti/bin/

    This folder contains scripts that are run by STI:

    • assemble

      Is used to install the sources into location from 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 file with commonly used modules.

  • test/

    This folder is containing STI test framework with simple server.

    • setup-test-app/

      Simple gunicorn application used for testing purposes in the STI test framework.

    • standalone-test-app/

      Simple standalone application used for testing purposes in the STI test framework.

    • run

      Script that runs the STI test framework.

• hack/

  Folder contains scripts which are responsible for build and test actions performed by the Makefile.

Image name structure

Structure: openshift/1-2-3

1. Platform name - python
2. Platform version(without dots)
3. Base builder image - centos7/rhel7

Examples: openshift/python-33-centos7, openshift/python-33-rhel7

Environment variables

To set these environment variables, you can place them into .sti/environment file inside your source code repository.

• APP_FILE

  This variable specifies file name (defaults to app.py) passed to the python interpreter which is responsible for launching application.

• APP_MODULE

  This variable specifies WSGI callable. It is of the pattern $(MODULE_NAME):$(VARIABLE_NAME), where module name is a full dotted path and the variable name refers to a inside the specified module. If using setup.py for installing the application the module name can be read from that file and variable will default to application, eg. see setup-test-app.

• APP_CONFIG

  This variable indicates path to a module which contains gunicorn configuration.