With https://github.com/NixOS/nix/pull/9839, the `storeUri` field is
much better structured, so we can use it while still opening the SSH
connection ourselves.
Nixpkgs only contains a `hydra_unstable`, not `hydra`, package, so
adjust the default accordingly, and then override it to our package in
the separate module which does that.
This fixes:
> Caught exception in Hydra::Controller::Root->realisations "Undefined subroutine &Hydra::Controller::Root::queryRawRealisation called at /nix/store/v842xb35ph8ka1yi1xanjhk4xh1pn5nm-hydra-2024-04-22/libexec/hydra/lib/Hydra/Controller/Root.pm line 371."
Re-creating `nix-next` after using it in #1375.
Flake lock file updates:
• Updated input 'nix':
'github:NixOS/nix/60824fa97c588a0faf68ea61260a47e388b0a4e5' (2024-04-11)
→ 'github:NixOS/nix/aa438b8fbaebbbdb922655127053c4e8ea3e55bb' (2024-04-12)
When content addressed derivations are built on the hydra server,
one may run into an issue where some builds suddenly don't load anymore.
This seems to be caused by outPaths that are NULL (which is
allowed for ca-derivations). Filter them out to prevent querying the
database for them, which is not supported by the database abstraction
layer that's currently in use.
On my instance this appears to resolve the issue.
I feel like I might be doing this at the wrong abstraction layer, but on
the other hand -- it seems to resolve it and it also doesn't really look
like it will hurt anything.
The test added in a previous commit uncovers this issue, and this commit
resolves it. So I'm happy with this patch for now.
The issue I was seeing on my server:
hydra-server[2549]: [error] Couldn't render template "undef error - DBIx::Class::SQLMaker::ClassicExtensions::puke(): Fatal: NULL-within-IN not implemented: The upcoming SQL::Abstract::Classic 2.0 will emit the logically correct SQL instead of raising this exception. at /nix/store/<hash>-hydra-unstable-2024-03-08_nix_2_20/libexec/hydra/lib/Hydra/Helper/Nix.pm line 190
See also short discussion here: https://github.com/NixOS/nixpkgs/pull/297392#issuecomment-2035366263
Closes#1336
When restarting postgresql, the connections are still reused in
`hydra-queue-runner` causing errors like this
main thread: Lost connection to the database server.
queue monitor: Lost connection to the database server.
and no more builds being processed.
`hydra-evaluator` doesn't have that issue since it crashes right away.
We could let it retry indefinitely as well (see below), but I don't
want to change too much.
If the DB is still unreachable 10s later, the process will stop with a
non-zero exit code because of a missing DB connection. This however
isn't such a big deal because it will be immediately restarted
afterwards. With the current configuration, Hydra will never give up,
but restart (and retry) infinitely. To me that seems reasonable, i.e. to
retry DB connections on a long-running process. If this doesn't work
out, the monitoring should fire anyways because the queue fills up, but
I'm open to discuss that.
Please note that this isn't reproducible with the DB and the queue
runner on the same machine when using `services.hydra-dev`, because of
the `Requires=` dependency `hydra-queue-runner.service` ->
`hydra-init.service` -> `postgresql.service` that causes the queue
runner to be restarted on `systemctl restart postgresql`.
Internally, Hydra uses Nix's pool data structure: it basically has N
slots (here DB connections) and whenever a new one is requested, an idle
slot is provided or a new one is created (when N slots are active, it'll
be waited until one slot is free). The issue in the code here is however
that whenever an error is encountered, the slot is released, however the
same broken connection will be reused the next time. By using
`Pool::Handle::markBad`, Nix will drop a broken slot. This is now being
done when `pqxx::broken_connection` was caught.
This was the source of a flaky test because sometimes hydra-notify was
quick enough to send out `buildStarted` and sometimes it apparently
wasn't which was quickly spottable with `nix build --rebuild`.
Removing that status update doesn't make a difference functionally,
gitea doesn't differentiate between "queued" and "running", so we send
the same status ("pending") out on both events, so we'd even safe one
avoidable request.
It's a pet peeve from me when logging into my personal Hydra that I
always have to press the button rather than hitting Return after entering
my password.
Reason for that is that the form doesn't have a "submit" button, so far
it was always listened to the "click" event. Submit does that and you
can hit Return alternatively.
