[BUG] `'version' is obsolete`

[frepke]

Description

After updating to version v2.25.0, the command docker compose pull docker-compose.yaml gives the error 'version' is obsolete

Steps To Reproduce

No response

Compose Version

v2.25.0

Docker Environment

Client: Docker Engine - Community
 Version:    24.0.7
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.12.1
    Path:     /root/.docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.25.0
    Path:     /root/.docker/cli-plugins/docker-compose

Server:
 Containers: 27
  Running: 27
  Paused: 0
  Stopped: 0
 Images: 24
 Server Version: 24.0.7
 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: inactive
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 3dd1e886e55dd695541fdcd67420c2888645a495
 runc version: v1.1.10-0-g18a0cb0
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.5.13-1-pve
 Operating System: Debian GNU/Linux 12 (bookworm)
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 6.723GiB
 Name: hpt630
 ID: beea869f-20a2-4a3f-a514-6ff0f77b5433
 Docker Root Dir: /srv/dev-disk-by-uuid-c1677ca2-07a1-4495-b5c3-ec3f921e2e60/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

Anything else?

No response

[Xeckt]

As I recall, this isn't a bug, version is only informative since a long time ago now. You can use loose options and you don't need it, check the spec:

https://github.com/compose-spec/compose-spec/blob/master/spec.md#version-and-name-top-level-elements

[frepke]

As I recall, this isn't a bug, version is only informative since a long time ago now. You can use loose options and you don't need it, check the spec:

https://github.com/compose-spec/compose-spec/blob/master/spec.md#version-and-name-top-level-elements

Thanks, didn't know that

[frepke]

@Xeckt gave the answer

[HenriWahl]

How will docker-compose.yml files for versions 2.x and 3.x be distinguished without the version tag?

[bkraul]

How will docker-compose.yml files for versions 2.x and 3.x be distinguished without the version tag?

I have the same question. How is this going to work...there are definitely differences between 2.x and 3.x that are not compatible with one another?

[luciangabor]

The version had (and in one case still has) a very ... limited relevance. It's purpose was to ... limit what you were allowed to write in those yaml files. The only case where that's still "relevant" is for docker stack.

The current file format is more of a "descendant" of the 2.x series and the 3.x series is, again, only relevant for docker stack, where 2.x had no ... relevance.

I'm glad it's gone. It was tiring to see "3" as version

[rseymour]

Could the docs be updated?