`gitlab-sardinecake-executor` - gitlab-runner integration

The gitlab-sardinecake-executor can be used for running GitLab-CI jobs within VMs managed by sardinecake.

Configuration

gitlab-runner

Tell gitlab-runner (via /etc/gitlab-runner/config.toml) to use sardinecake as the custom executor:

[[runners]]
  # ...
  builds_dir = "/home/vagrant/build"
  cache_dir = "/home/vagrant/cache"
  executor = "custom"

  [runners.custom]
    config_exec = "gitlab-sardinecake-executor"
    config_args = [ "config" ]
    prepare_exec = "gitlab-sardinecake-executor"
    prepare_args = [ "prepare" ]
    run_exec = "gitlab-sardinecake-executor"
    run_args = [ "run" ]
    cleanup_exec = "gitlab-sardinecake-executor"
    cleanup_args = [ "cleanup" ]

gitlab-sardinecake-executor

gitlab-sardinecake-executor looks for INI-style configuration files in

/etc/gitlab-runner/gitlab-sardinecake-executor.ini
~/.config/gitlab-runner/gitlab-sardinecake-executor.ini (in the home directory of the user running gitlab-sardinecake-executor)

[DEFAULT]
# how to connect to the sardinecake daemon
connect = qemu:///system
# where the downloaded OCI containers are stored
ocidir = /var/lib/sardinecake/OCI/
# where the extracted VMs are stored
vmdir = /var/lib/sardinecake/VMs/

See examples/gitlab-sardinecake-executor.ini

gitlab-ci.yml

Now you can use libvirt VMs in your .gitlab-ci.yml:

# You can use any libvirt VM the executor knows about
image: registry.example.org/sardines/debian12:latest

test:
  # In case you tagged runners that have
  # GitLab sardinecake Executor configured on them
  tags:
    - sardinecake

  script:
    - uname -a

Caveats

sardinecake VMs can be rather large. E.g. a Windows VM with various MSYS2/MinGW flavours installed can easily require a disk-image that takes 60GB. In the sardinecake OCI containers, these disk images are stored compressed (about ½ the size).

Nevertheless, when cloning a VM for the first time, the data has to be downloaded and uncompressed, which may take a while.