If a data only container starts with the same name than the active container, compose fails

[MBuffenoir]

Example docker-compose.yml:

dbdata:
  image: postgres:9.3
  command: echo "data only container (might already exists)"

db:
  image: postgres:9.3
  environment:
    DB_PASSWORD: postgres
    DB_USER: postgres
    DB_NAME: postgres
  ports:
    - "5432:5432"
  volumes_from: 
    - dbdata

Error raised is:
A service can not mount itself as volume

I believe the error is due to the usage of "in" here:
https://github.com/docker/compose/blob/master/compose/project.py#L38

[thaJeztah]

Ah, interesting :)

@aanand I wonder if this can be tweaked as well, now that labels are used?

[kojiromike]

I couldn't reproduce this behavior with docker-compose 1.3.0 dev (889d363). I tried this simplified test case:

aa:
    image: busybox
    volumes:
        - /foo
    command: echo 'oof'
a:
    image: busybox
    volumes_from:
        - aa

And then I tried OP's original example. I tried with both up and run. I did not get an error in any of those four attempts.

[dnephin]

The "in" on that line means "in the list" not "not in the string".

If this is still an issue please feel free to re-open with an update config and the full output of the docker-compose command you ran.

[richfletcher]

For the benefit of future searchers, this appears to be caused when a string is used as the value of volumes_from instead of a list. Then, the 'in' above checks for a substring of the given value for volumes_from.

Of course, a possible enhancement could be to either refuse a string or automatically listify it.

[dnephin]

Ah, this should be fixed by #129