potential issue with GitHub svn checkouts on Ubuntu

[Roland Haas]

While testing the ET on various Linux distributions @Steven R. Brandt found that, with some level of repeatability, checking out ExternalLibraries hosted on GitHub via svn would lead to error messages of the form

Warning: Could not checkout module ExternalLibraries/OpenBLAS
svn: E170000: URL 'https://github.com/EinsteinToolkit/ExternalLibraries-OpenBLAS.git/trunk' doesn't exist

Directly calling svn info on the repository URL gives:

svn info https://github.com/EinsteinToolkit/ExternalLibraries-OpenBLAS.git/trunk
svn: warning: W170000: URL 'https://github.com/EinsteinToolkit/ExternalLibraries-OpenBLAS.git/trunk' non-existent in revision 233

svn: E200009: Could not display info for all targets because some targets don't exist

indicating that svn could talk to the GtiHub server, otherwise it would not know of the revision number 233, but somehow was told that there is nothing present.

This does not happen with Fedora, Centos 7, OpenSuSE, Debian and was so far only observed on Ubuntu (16.04 and 20.04) and Mint.

@Roland Haas confirmed the issue in a Ubuntu VM ruling out networking issues.

The same svn version (version 1.13.0 (r1867053)) works without problems on a Debian laptop.

If this persists we may want to switch over to git only checkouts, which seems to have worked even for GitHub, and re-investigate if the, already present, --shallow option of GetComponents, is fully functional.

[Roland Haas]

Shallow clones had issues filed against them: #942 and #2070 in particular it seems to have problems with branches, which would rule out its use in a release.

[Roland Haas]

This happened as well during the ET ICERM workshop on 2020-09-18 with ExternalLibraries/MPI hosted on github. It seems github does not return an error message that GetComponents identifies and one ends up with no error message but one repository short since MPI ends up being an empty repository (but not fully missing).

Might be an rate limit issue on GitHub’s end.

[Roland Haas]

The issue most likely still exists but since git hash be9c164 "einsteintoolkit.th: use git checkout for RePrimAnd" of manifest and git hash 15eac20 "GetComponents: max --shallow and --branch work together (#6)" (sic) of CRL we no longer use svn in the ET thornlist, instead relying on shallow git checkouts.

So most likely the issue will no longer happen to new installs.

[Roland Haas]

Nothing we can do to fix really, since it is a GitHub problem and nothing we control. Just why it (mostly) affects Ubuntu (and WSL which is also Ubuntu), is not clear.