[BUG] Compose with OCI artifacts is failing on Windows

[mikesir87]

Description

I'm unable to launch Compose stacks on Windows machines that are sourced from OCI artifacts.

Steps To Reproduce

1. Run command:

   docker compose -f oci://dockersamples/labspace-mcp-gateway config

See error:

CreateFile C:\Users\mikesir87\oci:\dockersamples\.env: The filename, directory name, or volume label syntax is incorrect.

Compose Version

Docker Compose version v5.0.2

Docker Environment

Client:
 Version:    29.2.0
 Context:    desktop-linux
 Debug Mode: false
 Plugins:
  ai: Docker AI Agent - Ask Gordon (Docker Inc.)
    Version:  v1.17.2
    Path:     C:\Program Files\Docker\cli-plugins\docker-ai.exe
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.31.1-desktop.1
    Path:     C:\Program Files\Docker\cli-plugins\docker-buildx.exe
  compose: Docker Compose (Docker Inc.)
    Version:  v5.0.2
    Path:     C:\Program Files\Docker\cli-plugins\docker-compose.exe
  debug: Get a shell into any image or container (Docker Inc.)
    Version:  0.0.47
    Path:     C:\Program Files\Docker\cli-plugins\docker-debug.exe
  desktop: Docker Desktop commands (Docker Inc.)
    Version:  v0.3.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-desktop.exe
  extension: Manages Docker extensions (Docker Inc.)
    Version:  v0.2.31
    Path:     C:\Program Files\Docker\cli-plugins\docker-extension.exe
  init: Creates Docker-related starter files for your project (Docker Inc.)
    Version:  v1.4.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-init.exe
  mcp: Docker MCP Plugin (Docker Inc.)
    Version:  v0.38.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-mcp.exe
  model: Docker Model Runner (Docker Inc.)
    Version:  v1.0.8
    Path:     C:\Program Files\Docker\cli-plugins\docker-model.exe
  offload: Docker Offload (Docker Inc.)
    Version:  v0.5.42
    Path:     C:\Program Files\Docker\cli-plugins\docker-offload.exe
  pass: Docker Pass Secrets Manager Plugin (beta) (Docker Inc.)
    Version:  v0.0.24
    Path:     C:\Program Files\Docker\cli-plugins\docker-pass.exe
  sandbox: Docker Sandbox (Docker Inc.)
    Version:  v0.11.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-sandbox.exe
  sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc.)
    Version:  0.6.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-sbom.exe
  scout: Docker Scout (Docker Inc.)
    Version:  v1.19.0
    Path:     C:\Program Files\Docker\cli-plugins\docker-scout.exe

Server:
 Containers: 6
  Running: 0
  Paused: 0
  Stopped: 6
 Images: 76
 Server Version: 29.2.0
 Storage Driver: overlayfs
  driver-type: io.containerd.snapshotter.v1
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 CDI spec directories:
  /etc/cdi
  /var/run/cdi
 Discovered Devices:
  cdi: docker.com/gpu=webgpu
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 nvidia runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: dea7da592f5d1d2b7755e3a161be07f43fad8f75
 runc version: v1.3.4-0-gd6d73eb8
 init version: de40ad0
 Security Options:
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.6.87.2-microsoft-standard-WSL2
 Operating System: Docker Desktop
 OSType: linux
 Architecture: aarch64
 CPUs: 12
 Total Memory: 15.37GiB
 Name: docker-desktop
 ID: d5353205-c6de-4882-bc73-dcd3460c1cb4
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 HTTP Proxy: http.docker.internal:3128
 HTTPS Proxy: http.docker.internal:3128
 No Proxy: hubproxy.docker.internal
 Labels:
  com.docker.desktop.address=npipe://\\.\pipe\docker_cli
 Experimental: false
 Insecure Registries:
  hubproxy.docker.internal:5555
  ::1/128
  127.0.0.0/8
 Live Restore Enabled: false
 Firewall Backend: iptables

Anything else?

No response

[mikesir87]

Reverting my machine back to v5.0.1 still showed the error, where v5.0.0 did not. Therefore, regression is between v5.0.0 and v5.0.1.

[thaJeztah]

Just from the error, I think the path it's using is invalid due to the colon (:) being in there;

C:\Users\mikesir87\oci:\dockersamples\.env

Wonder if something is trying to concatenate a project path, perhaps trimming the project dir (/dockersamples/labspace-mcp-gateway), enduing up with the remainder (oct:/) and using that to set the path to store things.

I don't have a Windows machine, but tried running the command in a docker-in-docker container to see what files it produces on Linux (using docker diff as an easy way to see what files are touched 😅);

/ # docker compose version
Docker Compose version v5.0.2
/ # docker compose -f oci://dockersamples/labspace-mcp-gateway config
INFO[0002] fetch failed after status: 404 Not Found      host=registry-1.docker.io spanID=4c4984f11dfbcc55 traceID=df042b6ccc5cad9568c22afc510b3b80
INFO[0003] fetch failed after status: 404 Not Found      host=registry-1.docker.io spanID=4c4984f11dfbcc55 traceID=df042b6ccc5cad9568c22afc510b3b80
INFO[0004] fetch failed after status: 404 Not Found      host=registry-1.docker.io spanID=4c4984f11dfbcc55 traceID=df042b6ccc5cad9568c22afc510b3b80
WARN[0005] The "CONTENT_REPO_URL" variable is not set. Defaulting to a blank string.
project name must not be empty

Looking at the diff of the container;

docker diff 5d28ec7ac180 | grep root
C /root
A /root/.ash_history
A /root/.cache
A /root/.cache/docker-compose
A /root/.cache/docker-compose/34eb11bf8af4bee251fe63bc196f81cb240f550eaac1823a7e75467de43d8428
A /root/.cache/docker-compose/34eb11bf8af4bee251fe63bc196f81cb240f550eaac1823a7e75467de43d8428/compose.yaml