docker-py package breaks using docker-compose

[timja]

Issue Type

• Bug report

Molecule and Ansible details

• Molecule installation method: One of source, pip
  pip
• Ansible installation method: One of source, pip, OS package
  os package

Desired Behaviour

I can use docker-compose and molecule on the same machine

Actual Behaviour (Bug report only)

Installing docker-py conflicts with the new package docker

Traceback (most recent call last):
  File "/bin/docker-compose", line 7, in <module>
    from compose.cli.main import main
  File "/usr/lib/python2.7/site-packages/compose/cli/main.py", line 20, in <module>
    from ..bundle import get_image_digests
  File "/usr/lib/python2.7/site-packages/compose/bundle.py", line 13, in <module>
    from .network import get_network_defs_for_service
  File "/usr/lib/python2.7/site-packages/compose/network.py", line 7, in <module>
    from docker.types import IPAMConfig
ImportError: cannot import name IPAMConfig

See:
docker/compose#4401
docker/docker-py#1431

docker-py appears to be obsoleted and docker is the new pip package

[abtreece]

Docker changed the name of the Docker Python SDK to just docker when they bumped to version 2. The last docker-py version is 1.10.6. Molecule is only capable of using docker-py due to changes that have been made to the API in v2. AFAIK we won't be supporting the v2 docker b/c molecule is going to transition to using the Ansible implementation of Docker.

As you've discovered you can't have both docker-py and docker installed which is by design by Docker.

[abtreece]

Thinking about this more... in order to use docker-compose and molecule together you will likely need to install docker-compose via a method other than pip. On a Mac or Windows machine docker-compose comes with the installation of Docker Engine. You can also pull down the docker-compose binary by itself via a curl command documented here... https://docs.docker.com/compose/install/

[retr0h]

AFAIK we won't be supporting the v2 docker b/c molecule is going to transition to using the Ansible implementation of Docker.

Also, the Ansible 2.2 docker_ modules require docker-py, so I probably wont be spending effort porting Molecule v1 to the docker pip package.

[retr0h]

Thinking about this more... in order to use docker-compose and molecule together you will likely need to install docker-compose via a method other than pip. On a Mac or Windows machine docker-compose comes with the installation of Docker Engine. You can also pull down the docker-compose binary by itself via a curl command documented here... https://docs.docker.com/compose/install/

Good point as well. I can run Molecule and the entire docker toolchain, since I have installed docker using the Docker installer. Not through pip.

[retr0h]

Won't be moving to docker anytime soon. See workarounds above.

[timja]

In case anyone is interested ansible devel branch supports both docker-py and docker
Here is the commit that introduced support:
ansible/ansible@e2a1ce2

[timja]

@abtreece @retr0h The workaround of installing the compose binary from somewhere other than pip no longer works.

docker-compose has added a check to see if docker-py exists and fails fast with:

ERROR: Dependency conflict: an older version of the 'docker-py' package is polluting the namespace. Run the following command to remedy the issue:
pip uninstall docker docker-py; pip install docker

Is there another workaround?

[retr0h]

Is there another workaround?

Run molecule in a virtualenv? Since the bug report is about running docker-compose and molecule on the same system, you simply need to run molecule in a venv.

[retr0h]

@kireledan Would you be interested in porting Molecule to the new docker package vs docker-py?

[kireledan]

Sure. I'll take a look