Crash on Empty Ports Specification

[cscortes]

If you define a ports section, but leave it empty. It will cause podman-compose to crash on "up" command.

example yml:

version: "3"

services:
  flask-service:
    build: ./flask
    container_name: flask-service
    restart: always

    # notice, we added a "z" so that we can be changing the 
    # file in the directory, and it will change in the container
    volumes:
      - ./flask/app:/opt/flask:z
    ports:  
      # using internal port to communicate to webserver
      # - 9090:9090

Fixed it like so (around line 465 in version 0.1.5):

  # added this extra check
   if not (cnt.get('ports') is None):
        for i in cnt.get('ports', []):
            podman_args.extend(['-p', i])

This is probably not the only place this happens, probably other empty sections will cause the same crash. Maybe the yml parser should be more strict and give an appropriate error message like: ERROR: Ports section is empty.

This is version 0.1.5.

[cornmail]

Same for empty volumes, with the following example:

version: "3"

services:
  test:
    image: alpine
    volumes:
      # ./test:/test

podman-compose up outputs:

Traceback (most recent call last):
  File "~/.local/bin/podman-compose", line 11, in <module>
    sys.exit(main())
  File "~/.local/lib/python3.6/site-packages/podman_compose.py", line 2941, in main
    podman_compose.run()
  File "~/.local/lib/python3.6/site-packages/podman_compose.py", line 1423, in run
    cmd(self, args)
  File "~/.local/lib/python3.6/site-packages/podman_compose.py", line 1754, in wrapped
    return func(*args, **kw)
  File "~/.local/lib/python3.6/site-packages/podman_compose.py", line 2067, in compose_up
    podman_args = container_to_args(compose, cnt, detached=args.detach)
  File "~/.local/lib/python3.6/site-packages/podman_compose.py", line 900, in container_to_args
    for volume in cnt.get("volumes", []):
TypeError: 'NoneType' object is not iterable

In comparison, docker compose outputs a clearer message:

validating ~/test/docker-compose.yaml: services.test.volumes must be a list

My version is 1.0.6