To quote the function's comment:
Awful hack to handle timeouts in SQLite: just retry the transaction.
DBD::SQLite *has* a 30 second retry window, but apparently it
doesn't work.
Since SQLite is now dropped entirely, this wrapper can be removed
completely.
SQLite isn't properly supported by Hydra for a few years now[1], but
Hydra still depends on it. Apart from a slightly bigger closure this can
cause confusion by users since Hydra picks up SQLite rather than
PostgreSQL by default if HYDRA_DBI isn't configured properly[2]
[1] 78974abb69
[2] https://logs.nix.samueldr.com/nixos-dev/2020-04-10#3297342;
* 'eval_started' has the format '<tmpId>\t<project>\t<jobset>'.
* 'eval_failed' has the format '<tmpId>'. (The cause of the error can
be found in the database.)
* 'eval_added' has the format '<tmpId>:<evalId>'.
It now receives notifications about started/finished builds/steps via
PostgreSQL. This gets rid of the (substantial) overhead of starting
hydra-notify for every event. It also allows other programs (even on
other machines) to listen to Hydra notifications.
When using the "build" or "sysbuild" jobset input types in conjunction
with a binary cache store, the evaluator needs to be able to fetch
store paths from the binary cache. Typical usage:
store_uri = s3://nix-test-cache?secret-key=...
eval_substituter = s3://nix-test-cache
Also, the public key of the binary cache must be added to
binary-cache-public-keys in nix.conf, otherwise the local nix-daemon
won't allow the store paths to be copied over.
Also, remove support in hydra-eval-jobs for multiple jobset input
alternatives. The web interface hasn't supported this in a long
time. Thus we can use the regular "--arg" handler.
When creating a Hydra user with the `hydra-create-user` command, you can now
provide a SHA1 password hash with the `--password-hash` flag. This is useful for
the upcoming work on Fully Declarative Hydra, since the end user should not have
to specify plaintext passwords in their `configuration.nix` file.
As @dtzWill discovered, with the concurrent hydra-evaluator, there can
be multiple active transactions adding builds to the database. As a
result, builds can become visible in a non-monotonically increasing
order, breaking the queue monitor's assumption that build IDs only go
up.
The fix is to have hydra-eval-jobset provide the lowest build ID it
just added in the builds_added notification, and have the queue
monitor check from there.
Fixes#496.
This can take an excessive amount of time. For example, on
hydra.nixos.org, a call to hydra-notify takes 0.7s even if there are
no plugins. So for an eval with ~45K new builds, the calls to
hydra-notify add up to about 9 hours.
The proper fix would be to pass a list of build IDs, or an eval ID.
* The "Jobset" page now shows when evaluations are in progress (rather
than just pending).
* Restored the ability to do a single evaluation from the command line
by doing "hydra-evaluator <project> <jobset>".
* Fix some consistency issues between jobset status in PostgreSQL and
in hydra-evaluator. In particular, "lastCheckedTime" was never
updated internally.
Without this, if (failed or aborted) derivations have been
garbage-collected, there is no way to restart them, which is very
annoying. Now we set a forceEval flag in the jobset to cause it to be
re-evaluated even if none of the inputs have changed.
This rewrites the top-level loop of hydra-evaluator in C++. The Perl
stuff is moved into hydra-eval-jobset. (Rewriting the entire evaluator
would be nice but is a bit too much work.) The new version has some
advantages:
* It can run multiple jobset evaluations in parallel.
* It uses PostgreSQL notifications so it doesn't have to poll the
database. So if a jobset is triggered via the web interface or from
a GitHub / Bitbucket webhook, evaluation of the jobset will start
almost instantaneously (assuming the evaluator is not at its
concurrency limit).
* It imposes a timeout on evaluations. So if e.g. hydra-eval-jobset
hangs connecting to a Mercurial server, it will eventually be
killed.
This prevents the server from gradually filling up due to store paths
fetched by hydra-server that then get turned into a GC root by
hydra-update-gc-roots.
This allows fully declarative project specifications. This is best
illustrated by example:
* I create a new project, setting the declarative spec file to
"spec.json" and the declarative input to a git repo pointing
at git://github.com/shlevy/declarative-hydra-example.git
* hydra creates a special ".jobsets" jobset alongside the project
* Just before evaluating the ".jobsets" jobset, hydra fetches
declarative-hydra-example.git, reads spec.json as a jobset spec,
and updates the jobset's configuration accordingly:
{
"enabled": 1,
"hidden": false,
"description": "Jobsets",
"nixexprinput": "src",
"nixexprpath": "default.nix",
"checkinterval": 300,
"schedulingshares": 100,
"enableemail": false,
"emailoverride": "",
"keepnr": 3,
"inputs": {
"src": { "type": "git", "value": "git://github.com/shlevy/declarative-hydra-example.git", "emailresponsible": false },
"nixpkgs": { "type": "git", "value": "git://github.com/NixOS/nixpkgs.git release-16.03", "emailresponsible": false }
}
}
* When the "jobsets" job of the ".jobsets" jobset completes, hydra
reads its output as a JSON representation of a dictionary of
jobset specs and creates a jobset named "master" configured
accordingly (In this example, this is the same configuration as
.jobsets itself, except using release.nix instead of default.nix):
{
"enabled": 1,
"hidden": false,
"description": "js",
"nixexprinput": "src",
"nixexprpath": "release.nix",
"checkinterval": 300,
"schedulingshares": 100,
"enableemail": false,
"emailoverride": "",
"keepnr": 3,
"inputs": {
"src": { "type": "git", "value": "git://github.com/shlevy/declarative-hydra-example.git", "emailresponsible": false },
"nixpkgs": { "type": "git", "value": "git://github.com/NixOS/nixpkgs.git release-16.03", "emailresponsible": false }
}
}
This is currently done by a separate program that periodically
calls "hydra-queue-runner --status". Eventually, I'll do this
in the queue runner directly.
Fixes#220.
Hydra-queue-runner now no longer polls the queue periodically, but
instead sleeps until it receives a notification from PostgreSQL about
a change to the queue (build added, build cancelled or build
restarted).
Also, for the "build added" case, we now only check for builds with an
ID greater than the previous greatest ID. This is much more efficient
if the queue is large.
These give warnings in Perl >= 5.18:
given is experimental at /home/hydra/src/hydra/src/lib/Hydra/Helper/CatalystUtils.pm line 241.
when is experimental at /home/hydra/src/hydra/src/lib/Hydra/Helper/CatalystUtils.pm line 242.
...
Maximilian Bosch
Samuel Dionne-Riel