chore: add podman-compose fix and readme

[sunya-ch]

The current dev compose cannot be up with podman-compose command.

The main problem with podman-compose compatibility is the include directive, which is a Docker Compose v2.20+ feature that podman-compose doesn't fully support.

This PR adds that fix by explicitly merge including compose and add README with instruction to install and maintain for podman-compose compatibility.

Also, must note that the Scaphandre service is not available for ARM architecture (not available image for this architecture).

[vimalk78]

I tested this PR.

Testing Environment: Fedora 42, Podman 5.7.1, podman-compose 1.5.0, podman compose (docker-compose v5.0.1 backend)

---

What works

• docker compose up -d works out of the box with the standard compose.yaml (no changes needed)
• sudo podman compose up -d can start all 6 services using compose-podman.yaml
• All services come up, kepler reads RAPL, scaphandre and node-exporter collect metrics

Issues found

1. Grafana cannot reach Prometheus (network isolation)

Podman compose creates all networks with "isolate": "true" by default, which blocks inter-container communication. Docker compose does not do this.

Post "http://prometheus:9090/api/v1/query": dial tcp: lookup prometheus: i/o timeout

• Tried driver_opts: { isolate: "false" } in compose file → ignored (known bug)
• Tried creating networks manually (podman network create) and using external: true → DNS stops working entirely (connection refused on port 53)
• Docker compose on the same machine creates networks without isolation and DNS works fine

2. RAPL requires sudo

Docker daemon runs as root, so docker compose accesses RAPL without sudo. Podman is rootless by default, so sudo podman compose is required. This also means images are stored in root's storage, separate from the user's.

3. podman-compose (Python) vs podman compose (plugin)

• podman-compose: -d flag doesn't properly detach from terminal
• podman compose: -d works correctly (uses docker-compose backend)
• podman-compose: build --network=host not supported (builds fail when container can't reach internet)

4. include directive works with podman compose

Tested: podman compose -f compose.yaml config parses the include directive correctly. However, podman compose has a bug where dependencies from included files are not honored:

# Docker: starts prometheus (grafana's dependency from included file)
docker compose up grafana kepler-dev -d  → starts grafana, prometheus, kepler-dev, sushy-static ✅

# Podman: skips prometheus
sudo podman compose up grafana kepler-dev -d  → starts grafana, kepler-dev, sushy-static ❌

# Podman with flattened file: starts prometheus correctly
sudo podman compose -f compose-podman.yaml up grafana kepler-dev -d  → starts all 4 ✅

This validates the need for compose-podman.yaml to fix the dependency resolution.

5. SELinux (Fedora/RHEL)

When running rootless podman, bind mounts fail with permission denied due to SELinux. This is moot since sudo is required anyway for RAPL (sudo bypasses SELinux).

What we couldn't resolve

The network isolation issue (isolate: true) appears to be a Podman bug with no working workaround from the compose file. This means Grafana cannot connect to Prometheus using service names when using podman compose on native Linux.

Suggestions

1. Could you confirm your test environment? (macOS with podman machine may have different networking behavior)
2. Consider documenting in README-podman.md:
   • sudo is required for RAPL
   • Recommend podman compose over podman-compose
   • Known networking limitations on Linux
3. Minor: remove # Made with Bob comment (line 204)

[vprashar2929]

I think we can simplify this by having a single compose manifest. Adding this will increase the effort to maintain both manifests and duplication

[vimalk78]

I think we can simplify this by having a single compose manifest. Adding this will increase the effort to maintain both manifests and duplication

we cannot have single compose file. podman compose does not start dependencies from other include compose files, thats why we need a single composite compose file

[github-actions]

This PR is stale because it has been open 60 days with no activity.