Passing of environment variables does not match behaviour of docker-compose

[ztane]

Given compose file

---
version: '3.7'
services:
  test:
    image: ubuntu:20.04
    container_name: ubuntu
    environment:
    - FOO
    command: bash -c 'set | grep FOO'

and having the FOO set in .env, the variable is not passed into the container. Using - FOO=${FOO} works but either one works with docker-compose.

podman-compose version: 1.0.4
using podman version: 3.4.2

[john-waczak]

Just ran into the same issue

[acteq]

agree

[ifoughal]

I've also run into this issue, including the fact that I can't map my variables to my docker-compose values.

Eg:

---
version: '3.7'
services:
  test:
    image: $DIST:$VERSION
    container_name: $DIST
    environment:
    - FOO

This build would fail, as podman-compose fails to load the DIST and VERSION while attempting to spin up the container.

[l3ender]

We ran into issues when environment variables had quotes, e.g. - FOO="abc". Once we removed quotes, the - FOO=${FOO} approach worked.

[xmnlab]

I had the same issue here.

I am used to use something like this with docker-compose:

ports:
      - ${POSTGRES_PORT}:${POSTGRES_PORT}

and it gets the value from the .env file:

env_file:
      - ../.env

with podman-compose it doesn't work.

but if I export this variable before I run the podman-compose command, it works just fine.

[devurandom]

When running docker-compose -f docker-compose.yml -f docker-compose.extras.yml up with these files:

# docker-compose.yml
version: "3.2"
services:
  srv:
    environment:
      - MY_VAR

and

# docker-compose.extras.yml
version: "3.2"
  srv:
    environment:
      - MY_VAR=value

I get:

['podman', '--version', '']
using podman version: 4.3.1
Traceback (most recent call last):
  File "/usr/bin/podman-compose", line 33, in <module>
    sys.exit(load_entry_point('podman-compose==1.0.3', 'console_scripts', 'podman-compose')())
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 1774, in main
    podman_compose.run()
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 1021, in run
    self._parse_compose_file()
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 1090, in _parse_compose_file
    rec_merge(compose, content)
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 917, in rec_merge
    ret = rec_merge_one(target, source)
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 907, in rec_merge_one
    rec_merge_one(value, value2)
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 907, in rec_merge_one
    rec_merge_one(value, value2)
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 907, in rec_merge_one
    rec_merge_one(value, value2)
  File "/usr/lib/python3.11/site-packages/podman_compose.py", line 895, in rec_merge_one
    raise ValueError("can't merge value of {} of type {} and {}".format(key, type(value), type(value2)))
ValueError: can't merge value of HOSTING_DOMAIN of type <class 'NoneType'> and <class 'str'>

[superev12]

Also have this issue. For docker-compose.yaml with the content

services:
  postgres:
    image: "postgres"
    environment:
      - POSTGRES_USER=postgres
      - POSTGRES_PASSWORD=postgres
      - POSTGRES_DB=postgres
    ports:
      - "5432:5432"

When running the container,
POSTGRES_USER=user
POSTGRES_PASSWORD=pass
POSTGRES_DB=db

and port 5432 is instead mapped to 35432.

[Movion]

Any news for this? I also had the problem with podman-compose & mattermost as root when using variables

When im using the recommended .env file example and change postgres information, it is not forwarded to the container.

How to reproduce:
Use the env example file of mattermost, copy to .env, change the postgres information,:

POSTGRES_USER=mmuser
POSTGRES_PASSWORD=yourbelovedpassword
POSTGRES_DATABASE=mattermost

docker-compose.yml is having this information:

      # necessary Postgres options/variables
      - POSTGRES_USER
      - POSTGRES_PASSWORD
      - POSTGRES_DB

When you hit the command to start:
podman-compose --env-file=./.env -f docker-compose.yml -f docker-compose.nginx.yml up -d

The containers are starting up, but the variables are not forwarded
Seeing in the logs of the postgres container:

Fix:
It got fixed by adding the =${varibale} in the docker-compose.yml

      # necessary Postgres options/variables
      - POSTGRES_USER=${POSTGRES_USER}
      - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}
      - POSTGRES_DB=${POSTGRES_DB}

Than it works.. had todo this to all other variables too.

Docker also "recomment" todo this: https://docs.docker.com/compose/environment-variables/set-environment-variables/

The result is similar to the one above but Compose gives you a warning if the DEBUG variable is not set in the shell environment.

[mokibit]

@ztane thank you for opening an issue, it was fixed by: #1248.
@p12tic this issue can be closed.