Andy Wilkinson c5cae28261 Add support for plain text thread dumps to the threaddump endpoint
When a request that accepts text/plain is received, the threaddump
endpoint will now return a thread dump in plain text. The format of
this text is modelled after the output produced by JVisualVM when
connecting to a remote process over JMX. Note that this output does
not include all of the information in, for example, JStack's output
as it is not available via Java 8's ThreadInfo API.

Rather than the custom formatting logic, using ThreadInfo's toString()
method was considered but its output is documented as being undefined
and implementation specific. The implementation used while developing
this feature produced output that did not match that of JStack or
JVisualVM and truncated stack traces quite considerably.

At the time of writing the format produced by the endpoint could be
consumed by both Thread Dump Analyzer [1] and https://fastthread.io.

Closes gh-2339

[1] https://github.com/irockel/tda
2019-07-03 21:51:56 +01:00
..
2018-02-02 12:03:12 +00:00

= Spring Boot - Actuator

Spring Boot Actuator includes a number of additional features to help you monitor and
manage your application when it's pushed to production. You can choose to manage and
monitor your application using HTTP or JMX endpoints. Auditing, health and metrics
gathering can be automatically applied to your application. The
https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#production-ready[user guide]
covers the features in more detail.

== Enabling the Actuator
The simplest way to enable the features is to add a dependency to the
`spring-boot-starter-actuator` '`Starter`'. To add the actuator to a Maven-based project,
add the following '`Starter`' dependency:

[source,xml,indent=0]
----
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-actuator</artifactId>
		</dependency>
	</dependencies>
----

For Gradle, use the following declaration:

[indent=0]
----
	dependencies {
		compile("org.springframework.boot:spring-boot-starter-actuator")
	}
----

== Features
* **Endpoints** Actuator endpoints allow you to monitor and interact with your
  application. Spring Boot includes a number of built-in endpoints and you can also add
  your own. For example the `health` endpoint provides basic application health
  information. Run up a basic application and look at `/actuator/health`.
* **Metrics** Spring Boot Actuator provides dimensional metrics by integrating with
  https://micrometer.io[Micrometer].
* **Audit** Spring Boot Actuator has a flexible audit framework that will publish events
  to an `AuditEventRepository`. Once Spring Security is in play it automatically publishes
  authentication events by default. This can be very useful for reporting, and also to
  implement a lock-out policy based on authentication failures.