Quadlet: Handle multiple Exec= entries

[wnhrt]

Feature request description

Allowing multiple Exec= entries, like with Label=, would provide better readability and maintainability.

A prime example is the example docker-compose.yml of treafik with four long entries.
My own configuration is 18 arguments long and at exactly 1000 characters not easily manageable in a single line.

Suggest potential solution

Allowing multiple Exec= entries, like with Label=.

Have you considered any alternatives?

No. I am in the progress of migrating from docker compose and have not much experience with quadlets.
If there is an alternative approach, which I overlooked, please let me know.

Additional context

Related issue: #22027

I was able to start a container with multiple Exec= entries but podman ps shows only the arguments from the last entry.
This case, silently ignoring present configuration, seems more problematic than failing with an error.

[Container]
Image=docker.io/library/traefik
Exec="--api.insecure=true"
Exec="--providers.docker=true"
Exec="--providers.docker.exposedbydefault=false"
Exec="--entryPoints.web.address=:80"
Notify=true
Volume=%t/podman/podman.sock:/var/run/docker.sock
SecurityLabelDisable=true

CONTAINER ID  IMAGE                             COMMAND               CREATED        STATUS        PORTS       NAMES
1ab2d3e4f5g6  docker.io/library/traefik:latest  --entryPoints.web...  7 minutes ago  Up 7 minutes  80/tcp      systemd-traefik

[ygalblum]

When deciding whether to all the occurrences of a key or only the last, Quadlet follows what is supported by podman. For this reason, keys like Label may be set multiple times while for others that may be set only once, such as Entry, only the last occurrence is used. Furthermore, using only the last occurrence allows overriding the value in drop-in unit files.

As for you case, have you tried using the line continuation feature? For the example above it will look like:

[Container]
Image=docker.io/library/traefik
Exec=--api.insecure=true \
--providers.docker=true \
--providers.docker.exposedbydefault=false \
--entryPoints.web.address=:80
Notify=true
Volume=%t/podman/podman.sock:/var/run/docker.sock
SecurityLabelDisable=true