Query About Creating Volumes Without Services in Docker Compose v2

[fti-rgurav]

Description

In Docker Compose v1, I was able to create volumes independently using the following syntax:

version: '3.2'
volumes:
  volume1:
    driver: local
    name: "volume1"

However, upon migrating to Docker Compose v2, I attempted to use the same approach. Unfortunately, I encountered an error message "no service selected." It seems that the behavior has changed in v2 regarding how volumes are define

I'm looking for advice on how to create volumes in Docker Compose v2  without associating them with any specific service in Docker Compose v2. This was possible in v1, and I'm curious whether there's a workaround or new syntax in v2 that achieves the same result.

Steps To Reproduce

1. Up Docker Compose with the YAML file using v1 syntax to define volumes. Use the following YAML code:

version: '3.2'
volumes:
  volume1:
    driver: local
    name: "volume1"

2. Attempt to use the same file in Docker Compose v2 environment.
3. Observe the "no service selected" error.

Compose Version

Docker Compose version v2.20.3

Docker Environment

Client:
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.11.2
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx

Server:
 Containers: 16
  Running: 16
  Paused: 0
  Stopped: 0
 Images: 63
 Server Version: 23.0.1
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: journald
 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: 2456e983eb9e37e47538f59ea18f2043c9a73640
 runc version: v1.1.4-0-g5fd4c4d
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.1.0-11-amd64
 Operating System: Debian GNU/Linux 12 (bookworm)
 OSType: linux
 Architecture: x86_64
 CPUs: 8
 Total Memory: 15.27GiB
 Name: DEB-NUC11PAH-G6PA250003P9
 ID: 09e27f09-76c5-45dc-b50d-bb2b05611aac
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Experimental: true
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false
 Default Address Pools:
   Base: 172.128.0.1/9, Size: 16
   Base: fdd0:df31:dff5::1/104, Size: 112

Anything else?

No response

[ndeloof]

Docker Compose v2 removes unused resources from the model so that only required resources get created. This is why an "unused" volume won't be created. This decision makes more sense if you consider the introduction for profiles, where some service might be defined with related resources but disabled by default.

There's no workaround. Can you please elaborate on the use-case where you need volumes to be created but no service attached ?

[L-Trump]

Docker Compose v2 removes unused resources from the model so that only required resources get created. This is why an "unused" volume won't be created. This decision makes more sense if you consider the introduction for profiles, where some service might be defined with related resources but disabled by default.

There's no workaround. Can you please elaborate on the use-case where you need volumes to be created but no service attached ?

Since I use multiple compose files to manage multiple applications, sometimes I need a persistent volume for sharing files between applications, e.g. I want there to be a media volume that should not be belong to any of the fixed applications. Thus it may be a better way to create it in an independent compose file. Is it possible to provide an option of creating volume without checking whether it is used?

[ndeloof]

@L-Trump IIUC you use a single compose file as a yaml version for docker volume create XXX the refer to this volume as an external one in your other compose applications ?

[L-Trump]

@ndeloof Yes, that's what I want. This way I can avoid manually create volumes via the docker volume command and manage every thing in docker compose. A compose file is easier to manage than storing/remembering shell commands. Similarly, I think networks can be created in such a way so I don't need to bind a network to a specific proxy server.

[hrubi]

Note that this also affects the situation when I no longer have any services in the compose file and I want to clean up any leftover containers with docker compose up --remove-orphans. The new flag --all-resources works for this use case. Command docker compose down --remove-orphans works even without the new flag.

I am generating the compose file, so it more suitable for me to always run the same command and let docker compose figure out what it should do.