Compose: Docker-compose not able to get into bash if using entrypoint

[tarunlalwani]

I have a simple docker-compose.yml file

version: '2'

services:
  test:
     image: centos:6.7
     entrypoint: echo
     command: echo From compose

Now below is the command i execute

[root@localhost test-compose]# docker-compose run test
echo From compose
[root@localhost test-compose]# docker-compose run test this is best
this is best
[root@localhost test-compose]# docker-compose run --entrypoint "" test /bin/bash
/bin/bash
[root@localhost test-compose]# docker-compose run --entrypoint /bin/bash test
/bin/echo: /bin/echo: cannot execute binary file
[root@localhost test-compose]# docker-compose run --entrypoint /bin/bash test ""
/bin/echo: /bin/echo: cannot execute binary file

As you can see I am not able to get into bash any how. I am using Docker 1.11.1. If any more is needed please let me know

[shin-]

Yes, it would make sense for the CLI to be able to override the value found in the compose file.
Thank you for the report.

[tarunlalwani]

@shin, It's not an enhancement. It's mostly a bug i guess. Because the feature is listed in --help

[root@localhost pp21]# docker-compose run --help
Run a one-off command on a service.

For example:

    $ docker-compose run web python manage.py shell

By default, linked services will be started, unless they are already
running. If you do not want to start linked services, use
`docker-compose run --no-deps SERVICE COMMAND [ARGS...]`.

Usage: run [options] [-p PORT...] [-e KEY=VAL...] SERVICE [COMMAND] [ARGS...]

Options:
    -d                    Detached mode: Run container in the background, print
                          new container name.
    --name NAME           Assign a name to the container
    --entrypoint CMD      Override the entrypoint of the image.
    -e KEY=VAL            Set an environment variable (can be used multiple times)
    -u, --user=""         Run as specified username or uid
    --no-deps             Don't start linked services.
    --rm                  Remove container after run. Ignored in detached mode.
    -p, --publish=[]      Publish a container's port(s) to the host
    --service-ports       Run command with the service's ports enabled and mapped
                          to the host.
    -T                    Disable pseudo-tty allocation. By default `docker-compose run`
                          allocates a TTY.
    -w, --workdir=""      Working directory inside the container

[tarunlalwani]

@shin- , Thoughts on this?

[marpada]

+1

[aanand]

OK, I think we do have a bug here. When --entrypoint is passed to docker run, the container's Cmd is emptied out, even if the image sets a default. We should do the same with docker-compose run.

[aanand]

There's an additional bug where passing "" as the command is equivalent to passing nothing at all.

I've fixed both in https://github.com/docker/compose/pull/3718.

[4c74356b41]

db | /usr/bin/tail: /usr/bin/tail: cannot execute binary file
I don't think you did, thou ;)
Docker version 1.12.2, build bb80604, experimental
docker-compose version 1.8.1, build 004ddae

[JanBrinker]

@aanand can it be that this issue resurfaced? I'm having this exact issue, but I can't even override the entrypoint by giving the --entrypoint CMD arugment.

Docker version 17.03.1-ce, build c6d412e
docker-compose version 1.11.2, build dfed245

[shin-]

@JanBrinker Can you share your Compose file, the OS you're running on, and the exact command you're running + output so we can investigate?

[JanBrinker]

Sorry for bothering. I discovered it was a bad configuration on my end. I'm not very deep in docker and docker-compose yet. But thanks for asking :)

[sepastian]

How did you solve this, @JanBrinker? I'm facing the same issue with Docker version 17.03.1-ce, build c6d412e.