Utility to run arbitrary commands on a container

[n1ngu]

Most projects need some kind of initialization. So far I am copy-pasting this kind of scripts all over the projects

import pytest
import textwrap


@pytest.fixture(scope="session")
def backend_init(docker_services):

    def backend_run(command):
        docker_services._docker_compose.execute(
            "run --rm backend " + textwrap.dedent(command))

    backend_run("python -m django migrate")
    backend_run("python -m django configure")
    backend_run("""\
    bash <<EOF
    set -exo pipefail
    pip install pipenv
    pipenv install --dev --deploy
    python -m django load-fake-data
    EOF
    """)

    return

This sort of works, but I wonder if it would be worth to have some kind of utility to address this kind of need in pytest-docker.

Also, using docker_services._docker_compose.execute feels odd.

[n1ngu]

I realize I am writing this as a workaround on a docker_setup fixture shortcoming: the docker executor is not available as a fixture and you can't yield multiple compose subcommands interleaved with some python instructions, only a single docker compose subcommand.

Ideally I'd like to be able to write something like

@pytest.fixture(scope="session")
def docker_setup(docker_services):
    execute = docker_services._docker_compose.execute
    execute("up -d service-a service-b")
    docker_services.wait_until_responsive(check=is_service_a_ready)
    docker_services.wait_until_responsive(check=is_service_b_ready)
    execute(dedent("""\
    run --rm service-c my-shell << EOF
    something
    very
    complicated
    EOF
    """))
   execute("up -d service-c service-d")

but the docker_service fixture depends on the docker_setup fixture already!

[SRv6d]

This seems like a common use case and fairly trivial to implement. Is anyone working on this / are the maintainers open to MRs that would simplify this?