docker compose restricts project name, where the spec does not

[simue]

Description

As a follow up to #9216: docker compose denies creating projects with project names containing dots or uppercase letters. Looking at the compose spec, an arbitrary string can be provided as project name. There is no obvious restriction on the project name content:
https://github.com/compose-spec/compose-spec/blob/master/spec.md?plain=1#L48-L52
https://github.com/compose-spec/compose-spec/blob/master/schema/compose-spec.json#L14-L17

Steps to reproduce the issue:

1. create a project with arbitrary name containing dot and/or uppercase letters

Describe the results you received:
"settings_pittsburghFL" is not a valid project name

Describe the results you expected:
Project created successfully

Additional information you deem important (e.g. issue happens only occasionally):

Output of docker compose version:

Docker Compose version v2.6.1

Client:
 Context:    default
 Debug Mode: false

Server:
 Containers: 3
  Running: 1
  Paused: 0
  Stopped: 2
 Images: 7
 Server Version: 20.10.7
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 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.runtime.v1.linux runc io.containerd.runc.v2
 Default Runtime: runc
 Init Binary: docker-init
 containerd version:
 runc version:
 init version:
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.9.253-tegra
 Operating System: Ubuntu 18.04.6 LTS
 OSType: linux
 Architecture: aarch64
 CPUs: 4
 Total Memory: 31.18GiB
 Name: anon
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

Additional environment details:

[yar-sh]

To add to this issue, doesn't seem like name accepts environment variables. Sample docker-compose.yml file:

version: '3.9'
name: $TEST

x-test: &test
  TEST: $TEST

TEST='hello' docker compose convert produces:

name: test
services: {}
x-test:
  TEST: hello

But one would expect to get:

name: hello
services: {}
x-test:
  TEST: hello

[simue]

This behaviour is also observable with docker compose v2.9.0

[mbland]

I was bitten by this today, and after a little digging, found out what happened. The change was part of compose-spec/compose-go#261, which resolved #9434:

• https://github.com/compose-spec/compose-go/blob/fc7f2b85061ff576b5acefc2d9c59f51f2f5e301/cli/options.go#L64-L73
• https://github.com/compose-spec/compose-go/blob/fc7f2b85061ff576b5acefc2d9c59f51f2f5e301/loader/loader.go#L289-L294

If I'm interpreting correctly, the issue is that different project names could canonicalize to the same name, leading to a conflict and surprising behavior. The solution was to enforce only canonical names to begin with, that essentially must satisfy regexp.MustCompile("[a-z0-9_-]") without any trailing leading - or _ characters.

This landed in:

• https://github.com/compose-spec/compose-go/releases/tag/v1.2.5
• 65b827d
• https://github.com/docker/compose/releases/tag/v2.5.1

cc: @paulschuetz

[iMarv]

Had the same issue, but was not setting a name manually. It turns out the directory name in which the docker-compose.yml is located seems to become the default project name. Fix for me was to set a project name manually in the compose file, but I guess renaming the directory to something lowercase would work out aswell.