Update `EndpointDiscoverer` so that `@Endpoint` and `@EndpointExtension`
beans are created as late as possible.
Prior to this commit, endpoint beans and extension beans would be
created during the discovery phase which could cause early bean
initialization. The problem was especially nasty when using an embedded
servlet container since `ServletEndpointRegistrar` is loaded as the
container is initialized. This would trigger discovery and load all
endpoint beans, including the health endpoint, and all health indicator
beans.
Fixes gh-20714
Prior to this commit, there was a property server.error.include-details
that allowed configuration of the message and errors attributes in a
server error response.
This commit separates the control of the message and errors attributes
into two separate properties named server.error.include-message and
server.error.include-binding-errors. When the message attribute is
excluded from a servlet response, the value is changed from a
hard-coded text value to an empty value.
Fixes gh-20505
This commit updates HazelcastHealthIndicator and
HazelcastCacheMeterBinderProvider so that they work with
Hazelcast 4 while retaining compatibility with Hazelcast 3. Reflection
is used when necessary.
This commit also adds a smoke test that validates those features are
working when Hazelcast 4 is on the classpath.
Closes gh-21169
Prior to this commit, there was a cycle between `StatusAggregator` and
`SimpleStatusAggregator`, which caused a static initialization bug -
depending on which class (the implementation or its interface) was
loaded first.
This commit turns the static field of the `StatusAggregator` interface
into a static method to avoid this problem.
Fixes gh-21211
Prior to this commit, default error responses included the message
from a handled exception. When the exception was a BindException, the
error responses could also include an errors attribute containing the
details of the binding failure. These details could leak information
about the application.
This commit removes the exception message and binding errors detail
from error responses by default, and introduces a
`server.error.include-details` property that can be used to cause
these details to be included in the response.
Fixes gh-20505
Update the `HealthEndpointGroups` customization support to use a
post-processor rather than a mutable registry. Although this approach
is slightly less flexible, it removes a lot of complexity from the
`HealthEndpointGroups` code. Specifically, it allows us to drop the
`HealthEndpointGroupsRegistry` interface entirely.
The probe health groups are now added via the post-processor if they
aren't already defined. Unlike the previous implementation, users are
no longer able to customize status aggregation and http status code
mapping rules _unless_ they also re-define the health indicators that
are members of the group.
See gh-20962
Relocate probe auto-configuration from the `kubernetes` package to
`availability` since probes could also be used on other platforms.
The classes have also been renamed to named to `AvailabilityProbes...`
See gh-20962
Rename `LivenessProbeHealthIndicator` to `LivenessStateHealthIndicator`
and `ReadinessProbeHealthIndicator` to `ReadinessStateHealthIndicator`.
Also introduce a general purpose `AvailabilityStateHealthIndicator`
class.
See gh-20962
Create a general purpose `AvailabilityState` interface and refactor
the existing `LivenessState` and `ReadinessState` to use it. A single
`AvailabilityChangeEvent` is now used to carry all availability state
updates.
This commit also renames `ApplicationAvailabilityProvider` to
`ApplicationAvailabilityBean` and extracts an `ApplicationAvailability`
interface that other beans can inject. The helps to hide the event
listener method, which is really internal.
Finally the state enums have been renamed as follows:
- `LivenessState.LIVE` -> `LivenessState.CORRECT`
- `ReadinessState.READY` -> `ReadinessState.ACCEPTING_TRAFFIC`
- `ReadinessState.UNREADY` -> `ReadinessState.REFUSING_TRAFFIC`
See gh-20962
With its initial fix in gh-18444, the `WebClient` instrumentation would
record all CANCEL signals, including:
* when a `timeout` expires and the response has not been received
* when the client partially consumes the response body
Since the second use case is arguable intentional, this commit restricts
the instrumentation and thus avoids recording two events for a single
request in that case.
Closes gh-18444
Prior to this commit, cancelled client requests (for example as a result
of a `timeout()` reactor operator would not be recorded by Micrometer.
This commit instruments the cancelled signal for outgoing client
requests and assigns a status `CLIENT_ERROR`.
The cancellation can be intentional (triggering a timeout and falling
back on a faster alternative) or considered as an error. The intent
cannot be derived from the signal itself so we're considering it as a
client error.
Closes gh-18444
The system keyspace has a replication factor of 1 and is local to each
node; it is therefore recommended to query system.local with a
consistency level of ONE or LOCAL_ONE.
Stronger consistency levels may result in an Unavailable error, but this
does not mean that the node is down.
See gh-20709
Prior to this commit, `LivenessState` and `ReadinessState` were
immutable classes. This was done in order to have additional behavior
and information in those classes.
Because the current implementation doesn't need this, this commit turns
those classes into simple enums.
Additional state and information can be added to the
`*StateChangedEvent` classes.
See gh-19593
This commit upgrades the algorithm when trailing slash are to be
ignored. Previously a root URI (i.e. "/") would result to to empty
string which is an issue for monitoring system that requires tag values
to be non empty. If the URI is a single character, the trailing is not
applied and "/" is left as is.
Closes gh-20536
This commit moves the core Liveness and Readiness support to its own
`availability` package. We've made this a core concept independent of
Kubernetes.
Spring Boot now produces `LivenessStateChanged` and
`ReadinessStateChanged` events as part of the typical application
lifecycle.
Liveness and Readiness Probes (`HealthIndicator` components and health
groups) are still configured only when deployed on Kubernetes.
This commit also improves the documentation around Probes best practices
and container lifecycle considerations.
See gh-19593
Prior to this commit and as of Spring Boot 2.2.0, we would advise
developers to use the Actuator health groups to define custom "liveness"
and "readiness" groups and configure them with subsets of existing
health indicators.
This commit addresses several limitations with that approach.
First, `LivenessState` and `ReadinessState` are promoted to first class
concepts in Spring Boot applications. These states should not only based
on periodic health checks. Applications should be able to track changes
(and adapt their behavior) or update states (when an error happens).
The `ApplicationStateProvider` can be injected and used by applications
components to get the current application state. Components can also
track specific `ApplicationEvent` to be notified of changes, like
`ReadinessStateChangedEvent` and `LivenessStateChangedEvent`.
Components can also publish such events with an
`ApplicationEventPublisher`. Spring Boot will track startup event and
application context state to update the liveness and readiness state of
the application. This infrastructure is available in the
main spring-boot module.
If Spring Boot Actuator is on the classpath, additional
`HealthIndicator` will be contributed to the application:
`"LivenessProveHealthIndicator"` and `"ReadinessProbeHealthIndicator"`.
Also, "liveness" and "readiness" Health groups will be defined if
they're not configured already.
Closes gh-19593
Prior to this commit, `HealthContributor` would be exposed under the
main `HealthEndpoint` and subgroups, `HealthEndpointGroups`. Groups are
driven by configuration properties and there was no way to contribute
programmatically new groups.
This commit introduces the `HealthEndpointGroupsRegistry` (a mutable
version of `HealthEndpointGroups`) and a
`HealthEndpointGroupsRegistryCustomizer`. This allows configurations to
add/remove groups during Actuator auto-configuration.
Closes gh-20554
