Package: docker-jinja
docker-jinja - dj=================Extend your dockerfiles with Jinja2 syntax and logic.Create new filter and functions for Jinja with simple datasource files.Build status: [![Build Status](https://travis-ci.org/Grokzen/docker-jinja.svg?branch=master)](https://travis-ci.org/Grokzen/docker-jinja) [![Coverage Status](https://coveralls.io/repos/Grokzen/docker-jinja/badge.png)](https://coveralls.io/r/Grokzen/docker-jinja)Installation------------Install from pypi with `pip install docker-jinja`To install in development mode, first navigate to root of project and then run `pip install -r dev-requirements.txt; pip install -e .`. It is recommended to install inside a virtualenv to avoid conflicts with dependencies.Quickstart guide----------------Create a Dockerfile.jinja that contains all regular Dockerfile build steps and the jinja syntax. For exapmle:```$ cat Dockerfile.jinjaFROM {{ OS }}MAINTAINER {{ MAINTAINER }}ARG {{ ARG1 }}```Run `dj` command. For example:```dj --dockerfile Dockerfile.jinja --outfile Dockerfile --env OS=ubuntu:12.04 --env MAINTAINER=Grokzen --env ARG1=foobar --config test-config.json```And you will get the output:```FROM ubuntu:12.04MAINTAINER GrokzenARG foobar```Configuration files-------------------It is possible to create predefined configuration files with settings, enviroment variables and datasources.`dj` tries to load the following configuration files in the following order:- /etc/dj.yaml- /etc/dj.json- ~/.dj.yaml- ~/.dj.json- $CWD + '.dj.yaml'- $CWD + '.dj.json'YAML is the file format to prefer but json is also supported.Currently it is not possible to automatically load a config file next to the source Dockerfile.Datasources-----------If you want to extend the Jinja syntax with additional filters and global functions you have the datasource pattern to help you.A datasource file is a python script that can contain any code you want so you can extend `dj` to be capable to perform any task you want.You can tell `dj` to load a datasource file in multiple ways.- In any config file create a key `datasources` with a list of strings paths pointing to all files that `dj` should import. (Must be absolute path)- Point to a file with cli key -s/--datasource and `dj` will load that file. (Relative paths is supported)- Add a python file to contrib folder and it will auto load during execution.Global functions################A global function is a regular python function that you can call from jinja. These functions can be used to perform any usefull task you require.To create a global function you define a method within a datasource and its name should starts with `_global_` and then follow by the name you want to use in your Dockerfile.For example if you have the following code:```pythondef _global_foo():return "bar"```You can call it from jinja with:```ShellRUN echo '{{ foo() }}'```and it will render into```ShellRUN echo 'bar'```Filter functions################To create a new filter function you define a method within a datasource and its name should starts with `_filter_` and then follow by the name you want to use in your Dockerfile.For example if you have the following code```pythondef _filter_bar(arg):return arg.upper()```You can call it from jinja with:```ShellRUN echo '{{ "opa"|bar }}'```and it will render into```ShellRUN echo 'OPA'```Other rendering engines-----------------------Currently only Jinja2 is supported as rendering engineSupported python version------------------------- 2.7- 3.3- 3.4Python 3.2 will not be supported because Jinja2 is only supported on python >= 3.3 (Reference: http://jinja.pocoo.org/docs/intro/). If other rendering engines would be supported then python 3.2 can be supported for those engines.Contribute----------Open an Issue on github describing the problem you have.If you have a fix for the problem or want to add something to contrib library, open a PR with your fix. The PR must contain some test to verify that it work if it is a bugfix or new feature.  All tests in all supported python environments must pass on TravisCI before a PR will be accepted.All PR:s should have their commits squashed to a single commit.License=======See LICENSE file. (MIT)