The systemd extender is a scheduled execution that ensures we
repeatedly let systemd know during startup that we are still starting
up. We cancel this scheduled execution once the node has successfully
started up. This extender is wrapped in a set once, which we expose
directly. This commit addresses this by putting the extender behind a
getter, which hides the implementation detail that the extener is
wrapped in a set once. This cleans up some issues in tests, that
ensures we are not making assertions about the set once, but instead
about the extender.
When Elasticsearch is starting up, we schedule a thread to repeatedly
let systemd know that we are still in the process of starting up. Today
we use a non-final field for this. This commit changes this to be a set
once so we can mark the field as final, and get stronger guarantees when
reasoning about the state of execution here.
Today we pass the `RepositoriesService` to the searchable snapshots plugin
during the initialization of the `RepositoryModule`, forcing the plugin to be a
`RepositoryPlugin` even though it does not implement any repositories.
After discussion we decided it best for now to pass this in via
`Plugin#createComponents` instead, pending some future work in which plugins
can depend on services more dynamically.
This commit modifies the codebase so that our production code uses a
single instance of the IndexNameExpressionResolver class. This change
is being made in preparation for allowing name expression resolution
to be augmented by a plugin.
In order to remove some instances of IndexNameExpressionResolver, the
single instance is added as a parameter of Plugin#createComponents and
PersistentTaskPlugin#getPersistentTasksExecutor.
Backport of #52596
When we are notifying systemd that we are fully started up, it can be
that we do not notify systemd before its default timeout of sixty
seconds elapses (e.g., if we are upgrading on-disk metadata). In this
case, we need to notify systemd to extend this timeout so that we are
not abruptly terminated. We do this by repeatedly sending
EXTEND_TIMEOUT_USEC to extend the timeout by thirty seconds; we do this
every fifteen seconds. This will prevent systemd from abruptly
terminating us during a long startup. We cancel the scheduled execution
of this notification after we have successfully started up.
Backport of #48849. Update `.editorconfig` to make the Java settings the
default for all files, and then apply a 2-space indent to all `*.gradle`
files. Then reformat all the files.
These fields can be final, since they are set at construction, and
changing them after that could lead to some confusing test cases. This
commit allows the compiler to enforce that we never modify these values
during tests.
This commit more closely aligns the assertion that we are running in a
package distribution with disabling the systemd integration if somehow
we running on not a package distribution. This is, previously we had an
assertion that we are in a package distribution (RPM or Debian package)
but would disable the systemd integration if we are not on
Linux. Instead, we should disable the systemd integration if we are not
running in a package distribution. Because of our assertion, we expect
this to never hold, but we need a fallback for when this assertion is
violated and assertions are not enabled.
Today our systemd service defaults to a service type of simple. This
means that systemd assumes Elasticsearch is ready as soon as the
ExecStart (bin/elasticsearch) process is forked off. This means that the
service appears ready long before it actually is, so before it is ready
to receive requests. It also means that services that want to depend on
Elasticsearch being ready to start can not as there is not a reliable
mechanism to determine this. This commit changes the service type to
notify. This requires that Elasticsearch sends a notification message
via libsystemd sd_notify method. This commit does that by using JNA to
invoke this native method. Additionally, we use this integration to also
notify systemd when we are stopping.
Jason Tedor
David Turner
Jay Modi
Rory Hunter