bgio/plugins repository overview

⁠Description

Each python environment is loaded with an ubuntu base image and pyenv installed. The images also come with a version of python installed based on which tag you pull down.

⁠Supported Tags

bgio/plugins image currently supports the below tags. Each link is its Dockerfile:

• python2 [(python2/Dockerfile)][1]
• python3 [(python3/Dockerfile)][2]
• python2-onbuild [(python2/onbuild/Dockerfile)][3]
• python3-onbuild [(python3/onbuild/Dockerfile)][4]

⁠Usage

In order to run your plugin as a docker container, you first need to create a plugin. Let's assume you have a running beer-garden on localhost and you've written your plugin in python as follows:

from brewtils.decorators import command_registrar, plugin_param
from brewtils.plugin import RemotePlugin

@command_registrar
class HelloWorld(object):

    @plugin_param(key="message", type="String")
    def do_something(self, message):
        print(message)
        return message

if __name__ == "__main__":
  my_client = HelloWorld()
  my_plugin = RemotePlugin(my_client, name='hello-world', version='0.0.1',
                           bg_host='localhost', bg_port=2337, ssl_enabled=False)
  my_plugin.run()

Save that off as a file __main__.py. You should be able to run:

docker run -v $(pwd):/src bbgio/plugins:python2

Congratulations! Your plugin works! If you want to name your file something else you can do that, you just need to modify the run statement:

docker run -v $(pwd):/src bgio/plugins:python2 python /src/my_cool_filename.py

⁠onbuild Usage

The onbuild is useful if you have additional dependencies. It operates on two different files:

1. requirements.txt
2. install-prereqs.sh

For python images, it will take your requirements.txt file and feed it automatically to pip in order to make building derivative images easier. For most use cases, creating a Dockerfile in the base of your project directory with the line FROM bgio/plugins:python3-onbuild will be enough to create a stand-alone image for your project. If you have non-python dependencies that you need installed, you can write whatever you like in install-prereqs.sh and it will execute that. Let's assume you have a dependency on libssl-devel, you could add the following to your install-prereqs.sh:

apt-get install libssl-devel

Then you simply build your image and all the python & additional dependencies will be built for you.

While the onbuild variant is really useful for "getting off the ground running" (zero to Dockerized in a short period of time), it's not recommend for long-term usage within a project due to the lack of control over when on ONBUILD triggers fire. Once you've got handle on how your project functions within Docker, you'll probably want to adjust your Dockerfile to inherit from a non-onbuild variant and copy the commands from the onbuild variant Dockerfile (moving the ONBUILD lines to the end and remove the ONBUILD keywords) into your own file so that you have tighter control over them and more transparency for yourself and others looking at your Dockerfile as to what it does. This also makes it easier to add additional requirements as time goes on (such as installing more packages before performing the previously-ONBUILD steps).

⁠Author

loganasherjones [1]: https://github.com/beer-garden/beer-garden/blob/master/docker/dockerfiles/plugins/python2/Dockerfile⁠ [2]: https://github.com/beer-garden/beer-garden/blob/master/docker/dockerfiles/plugins/python3/Dockerfile⁠ [3]: https://github.com/beer-garden/beer-garden/blob/master/docker/dockerfiles/plugins/python2/onbuild/Dockerfile⁠ [4]: https://github.com/beer-garden/beer-garden/blob/master/docker/dockerfiles/plugins/python3/onbuild/Dockerfile⁠