We now kill active build steps when there are no more referring
builds. This is useful e.g. for preventing cancelled multi-hour TPC-H
benchmark runs from hogging build machines.
If two active steps of the same build failed, then the first would be
marked as "failed", but the second would end up as "orphaned", causing
it to be marked as "aborted" later on. Now it's correctly marked as
"failed".
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.
‘basicDrv.inputSrcs’ also contains the outputs of inputDrvs. These
don't necessarily exist in the local store, so copying them may cause
an exception. We should only copy the real inputSrcs.
Some Hydra API requests were vulnerable to XSRF attacks, e.g. you
could have a form on another website using http://hydra/logout as the
form action. So we now require POST requests to come from the same
origin.
Reported by Hans-Christian Esperer.
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.
Dashboards can now be marked as publically visible in the user
preferences. The dashboard URL has changed from /user/<name>/dashboard
to /dashboard/<name> because /user/<name> requires being logged in as
<name> or as an admin.
