If spring-hateoas is on the classpath and an MvcEndpoint returns a
@ResponseBody it will be extended and wrapped into a Resource with links.
All the existing endpoints that return sensible JSON data can be extended
this way (i.e. not /logfile). The HAL browser will also be added as an
endpoint if available on the classpath. Finally, asciidocs for the
Actuator endpoints are available as a separate jar file, which if
included in an app will also generate a new (HTTP) endpoint.
Fixes gh-1390
There is a new spring.factories entry for
org.springframework.boot.actuate.autoconfigure.EndpointWebMvcConfiguration
which loads extra beans into the MVC config for the Actuator.
If the management context is a child context all the beans go in the
child (except the Spring Security filter still). A big bonus is that
you can add WebConfigurerAdapters to configure static resources etc.
A new component called ManagementContextResolver can be used to
locate the ApplicationContext for the MVC endpoints.
Fixes gh-3345
for users to get started. It also makes it more flexible if different
aggregation keys are needed depending on the environment. The most
important new feature is the
spring.metrics.export.redis.aggregateKeyPattern configuration, which
fits the *.redis.key and prefix defaults. The aggregate reader uses
a prefix based on the key by default, with a naming convention that
the key starts with "keys.".
Users can add @ExportMetric[Reader,Writer] to readers and writers that
they want to participate in the default exporter. There is also still an
@ActuatorMetricWriter that is used for the legacy (non-Java8) Gauge and
CounterServices.
The redis export and aggregate use case is a lot nicer with this
shared data between the two component types.
Also made MetricExportProperties itself a Trigger (so the default
delay etc. can be configured via spring.metrics.export.*).
Different physical sources for the same logical metric just need to
publish them with a period-separated prefix, and this reader will
aggregate (by truncating the metric names, dropping the prefix).
Very useful (for instance) if multiple application instances are
feeding to a central (e.g. redis) repository and you want to
display the results. Useful in conjunction with a
MetricReaderPublicMetrics for hooking up to the /metrics endpoint.
This seems pretty efficient (approx 12M write/s as opposed to 2M with
the DefaultCounterService). N.B. there is no need to change most of
the rest of the metrics stuff because metrics are write-often, read-
seldom, so we don't need high performance reads as much.
The Spring Integration configuration and Dropwizard support has changed
a bit. Functionally very similar and probably opaque to users, but now
the messaging operates as an Exporter on a @Scheduled method, and
Dropwizard is a replacement [Gauge,Counter]Service.
Metrics are all
collected live in-memory (and can be very fast with Java 8), buffered
there and shipped out to a MessageChannel (if one exists with id
"metricsChannel") in a background thread.
We can still use Java 8 library APIs (like LongAdder) but to compile
to java 7 compatible byte code we have to forgo the use of lambdas :-(
and shorthand generics (<>).
Fixes gh-2682, fixes gh-2513 (for Java 8 and Dropwizard users).
Update AbstractEndpoint so that the `enable` property is optional and
when it not specified the `endpoints.enabled` property will be used.
This allows users to switch the way that endpoints are enabled. Rather
than opting-out specific endpoint enablement the `endpoints.enabled`
property can be set to `false` and specific endpoints can be opted-in.
Fixes gh-2102