docker_host_info: Filter containers by multiple labels

[yajo]

SUMMARY

Cannot filter for multiple labels.

ISSUE TYPE

• Feature Idea

COMPONENT NAME

docker_host_info

ADDITIONAL INFORMATION

This cannot work because we can't define the same key twice in a dict:

- name: find running docker containers
  register: docker_info
  docker_host_info:
    containers: yes
    containers_filters:
      label: com.docker.compose.project=myproject # THIS GETS IGNORED
      label: com.docker.compose.service=backup

Possible solutions:

1. Allow a list in containers_filters:

   - name: find running docker containers
     register: docker_info
     docker_host_info:
       containers: yes
       containers_filters:
         - label=com.docker.compose.project=myproject
         - label=com.docker.compose.service=backup

2. Allow a dict in containers_filters.label filter:

   - name: find running docker containers
     register: docker_info
     docker_host_info:
       containers: yes
       containers_filters:
         label:
           com.docker.compose.project: myproject
           com.docker.compose.service: backup

I have not tested, but I guess the same applies to images_filters, networks_filters and volumes_filters.

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Files identified in the description:

• plugins/modules/cloud/docker/docker_host_info.py

If these files are inaccurate, please update the component name section of the description or use the !component bot command.

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[ansibullbot]

cc @DBendit @WojciechowskiPiotr @akshay196 @chouseknecht @danihodovic @dariko @felixfontein @jwitko @kassiansun @tbouvet
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[felixfontein]

This is the interface provided by Docker itself: it wants a dictionary of filters. If we provide something more sophisticated, we probably have to parse and process this by ourselves.

[yajo]

But you can actually do that filtering with CLI, right?

[felixfontein]

No idea. Feel free to figure out how the CLI does it.

[yajo]

Definitely the CLI can do it:

I think you use docker-py behind the scenes, right? Its docs say you can pass a list to the label fiilter. That would easily map like this to ansible:

- name: find running docker containers
  register: docker_info
  docker_host_info:
    containers: yes
    containers_filters:
      label:
        - com.docker.compose.project=myproject
        - com.docker.compose.service=backup

[felixfontein]

I never claimed the CLI can't do it. I was just stating that I don't know whether it can do it (and honestly, I don't care if it can or not).

Feel free to create a PR to implement this.

[Ajpantuso]

@felixfontein, the OP referred to the higher-level API, but the API used by this module does in fact permit a list of labels.
I could do something like the following to allow lists to remain intact with minimal impact to the other modules. (With a doc update as well)

Update this to

def clean_dict_booleans_for_docker_api(data, allow_sequences=False):
    '''
    Go doesn't like Python booleans 'True' or 'False', while Ansible is just
    fine with them in YAML. As such, they need to be converted in cases where
    we pass dictionaries to the Docker API (e.g. docker_network's
    driver_options and docker_prune's filters).
    '''
    result = dict()
    if data is not None:
        for k, v in data.items():
            if allow_sequences and is_sequence(v):
                pass
            elif v is True:
                v = 'true'
            elif v is False:
                v = 'false'
            else:
                v = str(v)
            result[str(k)] = v
    return result

[felixfontein]

@Ajpantuso it's a bit more complicated, since the sequence's values have to (potentially) be adjusted as well. Besides that, it should work.