Unable to change mount point of mounted directories

[jlsalmon]

Hi folks,

I just ran into an issue where a build which uses a custom --builds-dir argument in the config stage failed due to spaces in the path (/Volumes/My Shared Files/...) in a component I don't have control over. I'm aware that the mount point can be changed via mount_virtiofs, but it doesn't seem to be possible to achieve this at the moment inside a GitLab job.

I tried changing the mountpoint in a pre_get_sources_script block in config.toml, but unfortunately the GitLab job environment has already been created by this point, and the buildsdir (and cachedir) are already hard-coded with the default mountpoint.

Would it be possible to provide a way to customise the builds dir on the guest to support non-default mount points? Perhaps with a syntax similar to tart's own --dir option, e.g. --builds-dir=/host/builds:/guest/builds?

Perhaps this could also be unified somehow with the --guest-builds-dir option? I tried using --guest-builds-dir but it's mutually exclusive with --builds-dir.

Many thanks in advance 🙏

[edigaryev]

I tried changing the mountpoint in a pre_get_sources_script block in config.toml, but unfortunately the GitLab job environment has already been created by this point, and the buildsdir (and cachedir) are already hard-coded with the default mountpoint.

You can work around this by creating a symbolic link:

ln -s "/Volumes/My Shared Files/buildsdir" /Users/admin/buildsdir

...and then passing the /Users/admin/buildsdir to the component I don't have control over.

[jlsalmon]

@edigaryev many thanks for the suggestion, unfortunately that doesn't seem to be a complete workaround for what I'm currently trying to do, since the component I don't have control over uses getcwd() which does not appear to resolve symlinks and returns the real path 🙁

[fkorotkov]

I guess we can try to change the default mount location given recent improvements to Tart. I've drafted the idea in #65. @edigaryev is on PTO until Monday and he'll take a look next week since he has more context.