docker stack config does not resolve values from .env

[membersound]

Description

I'm trying to set some variables like the image name from .env, to run it in docker swarm as follows:

docker stack deploy -c <(docker stack config -c docker-compose.yml) my-app

Problem: docker stack config loses tags that use values from .env file, see steps to reproduce.

Reproduce

cat docker-compose.yml:

services:
  app:
    image: $APPLICATION_IMAGE
      #env_file: '.env'
    ports:
      - 8090:8080

.env:
APPLICATION_IMAGE=my.docker.repo/my-app:latest

docker stack config -c docker-compose.yml:

services:
  app:
    ports:
    - mode: ingress
      target: 8080
      published: 8090
      protocol: tcp

Expected behavior

image tag should be present and filled with value from .env:

services:
  app:
    image: my.docker.repo/my-app:latest
    ports:
    - mode: ingress
      target: 8080
      published: 8090
      protocol: tcp

docker version

Client: Docker Engine - Community
 Version:           24.0.5
 API version:       1.43
 Go version:        go1.20.6
 Git commit:        ced0996
 Built:             Fri Jul 21 20:35:23 2023
 OS/Arch:           linux/amd64
 Context:           default

Server: Docker Engine - Community
 Engine:
  Version:          24.0.5
  API version:      1.43 (minimum version 1.12)
  Go version:       go1.20.6
  Git commit:       a61e2b4
  Built:            Fri Jul 21 20:35:23 2023
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.6.22
  GitCommit:        8165feabfdfe38c65b599c4993d227328c231fca
 runc:
  Version:          1.1.8
  GitCommit:        v1.1.8-0-g82f18fe
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

docker info

Client: Docker Engine - Community
 Version:    24.0.5
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.11.2
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.20.2
    Path:     /usr/libexec/docker/cli-plugins/docker-compose

Server:
 Containers: 34
  Running: 11
  Paused: 0
  Stopped: 23
 Images: 479
 Server Version: 24.0.5
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: systemd
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: active
  NodeID: m98663673nkszvyj3f2fnctvd
  Is Manager: true
  ClusterID: 4tigljlfpmc4aqt5yb2nrz7x6
  Managers: 1
  Nodes: 1
  Default Address Pool: 10.0.0.0/8  
  SubnetSize: 24
  Data Path Port: 4789
  Orchestration:
   Task History Retention Limit: 5
  Raft:
   Snapshot Interval: 10000
   Number of Old Snapshots to Retain: 0
   Heartbeat Tick: 1
   Election Tick: 10
  Dispatcher:
   Heartbeat Period: 5 seconds
  CA Configuration:
   Expiry Duration: 3 months
   Force Rotate: 0
  Autolock Managers: false
  Root Rotation In Progress: false
  Node Address: 192.168.134.214
  Manager Addresses:
   192.168.134.214:2377
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 8165feabfdfe38c65b599c4993d227328c231fca
 runc version: v1.1.8-0-g82f18fe
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 5.15.0-73-generic
 Operating System: Ubuntu 22.04.3 LTS
 OSType: linux
 Architecture: x86_64
 CPUs: 2
 Total Memory: 11.66GiB
 Name: svdev4
 ID: DKLD:FBO7:72JP:LPYR:JKGE:GKJR:CQEA:AWEC:HGNC:DFCZ:HDES:LN4H
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false
 Default Address Pools:
   Base: 11.0.0.0/16, Size: 24

Additional Info

No response

[thaJeztah]

This looks like a duplicate of #29133

closing this one, so that the conversation doesn't diverge.