On Thu, Dec 10, 2020 at 12:32:52PM -0500, Robert Haas wrote: > It would probably be good to fix as much of this as we can, but there > are a couple of cases I think would be particularly good to cover. One > is 'pg_basebackup -Ft -Xnone -D -', which tries to write the output as > a single tar file on standard output, injecting the backup_manifest > file into the tar file instead of writing it out separately as we > normally would. This case requires special handling in a few places > and it would be good to check that it actually works. The other is the > -z or -Z option, which produces a compressed tar file. > > Now, there's nothing to prevent us from running commands like this > from the pg_basebackup tests, but it doesn't seem like we could really > check anything meaningful. Perhaps we'd notice if the command exited > non-zero or didn't produce any output, but it would be nice to verify > that the resulting backups are actually correct. The way to do that > would seem to be to extract the tar file (and decompress it first, in > the -z/-Z case) and then run pg_verifybackup on the result and check > that it passes. However, as far as I can tell there's no guarantee > that the user has 'tar' or 'gunzip' installed on their system, so I > don't see a clean way to do this. A short (but perhaps incomplete) > search didn't turn up similar precedents in the existing tests. > > Any ideas?
I would probe for the commands with "tar -cf- anyfile | tar -xf-" and "echo foo | gzip | gunzip". If those fail, skip any test that relies on an unavailable command.
