Using a memory database causes tests/test_build to intermittently
fail, because using the same pysqlite3 connection object from multiple
threads - as was done so that the threads shared the same memory database
- is not, in the end, thread safe. One thread will stomp on the transaction
state of other threads, resulting in errors from starting a new transaction
when another is already in progress, or trying to commit a transaction
that is not in progress.
To avoid a significant speed penalty, the session-scope fixture sets up
a database in the pytest temporary directory, which will typically be on
tmpfs. Time to complete all tests:
memory backend: 38 seconds
file on tmpfs: 40 seconds
file on nvme ssd with btrfs: 137 seconds
MBSSQLAlchemy, which attempted to make the memory backend work, is removed.
Session hooks are installed on the Session class rather than on the
scoped_session instance - this works better when we're changing from
one database to another at test setup time.
No implementations of MBS are using Greenwave, and there are no current plans
to do so. Koji Resolver will be sufficient for any usecase dependent on gating.
There is a need to rebuild the module builds done in CentOS 9 Stream
internally in MBS to include them in RHEL. This is currenly a hard task,
because the RPM components included in a module are usually
taken from HEAD of the branch defined by their `ref` value.
For the rebuild task, it means we would have to ensure that the HEAD
of all RPM components points to right commit hash right before we start
rebuilding CentOS 9 Stream module in internal MBS. This is very hard
and fragile thing to do, especially if there are two different modules
using the RPM component from the same branch. This is prone to race
condition and makes the rebuilds quite complex and in some cases
not possible to do without force pushes to RPM component repositories
which is not acceptable by internal dist-git policy.
This commit fixes it by allowing overriding the commit hash while
submitting the module build. This helps in the mentioned situation,
because we can keep internal RPM components branches in 1:1 sync with
CentOS 9 Stream branches and HEAD can always point to the same commit
in both internal and CentOS 9 Stream repositories.
When the module rebuild is submitted in internal MBS,
we can use this new feature to override the `ref` for each RPM component
so it points to particular commit and the requirement for HEAD to point
to this commit is no longer there.
The `ref` is overriden only internally in MBS (but it is recorded in logs
and in XMD section), so the input modulemd file is not altered. This is
the same logic as used for other overrides (`buildrequire_overrides` or
`side_tag`).
This does not bring any security problem, because it is already possible
to use commit hash in `ref`, so the package maintainer can already change
the commit hash to any particular commit by using this `ref` value.
Signed-off-by: Jan Kaluza <jkaluza@redhat.com>
