activemq-artemis/docs/hacking-guide/_tests.adoc

= Tests

== Running Tests

To run the unit tests:
[,sh]
----
$ mvn -Ptests test
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Generating reports from unit tests:
[,sh]
----
$ mvn install site
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Running tests individually
[,sh]
----
$ mvn -Ptests -DfailIfNoTests=false -Dtest=<test-name> test
----
where `<test-name>` is the name of the Test class without its package name.

== Writing Tests

The broker is comprised of POJOs so it's simple to configure and run a broker instance and test particular functionality.
Even complex test-cases involving multiple clustered brokers are relatively easy to write.
Almost every test in the  test-suite follows this pattern - configure broker, start broker, test functionality, stop broker.

The test-suite uses JUnit to manage test execution and life-cycle.
Most tests extend https://github.com/apache/activemq-artemis/blob/main/artemis-server/src/test/java/org/apache/activemq/artemis/tests/util/ActiveMQTestBase.java[`org.apache.activemq.artemis.tests.util.ActiveMQTestBase`] which contains JUnit setup and tear-down methods as well as a wealth of utility functions to configure, start, manage, and stop brokers as well as perform other common tasks.

Check out https://github.com/apache/activemq-artemis/blob/main/tests/integration-tests/src/test/java/org/apache/activemq/artemis/tests/integration/SimpleTest.java[`org.apache.activemq.artemis.tests.integration.SimpleTest`].
It's a very simple test-case that extends `org.apache.activemq.artemis.tests.util.ActiveMQTestBase` and uses its methods to configure a server, run a test, and then `super.tearDown()` cleans it up once the test completes.
The test-case  includes comments to explain everything.
As the name implies, this is a simple test-case that demonstrates the most basic functionality of the test-suite.
A simple test like this takes less than a second to run on modern hardware.

Although `org.apache.activemq.artemis.tests.integration.SimpleTest` is simple it could be simpler still by extending https://github.com/apache/activemq-artemis/blob/main/artemis-server/src/test/java/org/apache/activemq/artemis/tests/util/SingleServerTestBase.java[`org.apache.activemq.artemis.tests.util.SingleServerTestBase`].
This class does all the setup of a simple server automatically and provides the test-case with a `ServerLocator`,  `ClientSessionFactory`, and `ClientSession` instance.
https://github.com/apache/activemq-artemis/blob/main//tests/integration-tests/src/test/java/org/apache/activemq/artemis/tests/integration/SingleServerSimpleTest.java[`org.apache.activemq.artemis.tests.integration.SingleServerSimpleTest`] is an example based on `org.apache.activemq.artemis.tests.integration.SimpleTest` but extends `org.apache.activemq.artemis.tests.util.SingleServerTestBase` which eliminates all the setup and class variables which are provided by `SingleServerTestBase` itself.

== Writing Web Tests

The broker has a web console based on https://github.com/hawtio/hawtio[hawtio] and the `smoke-tests` are used to test it.
For instance, the https://github.com/apache/activemq-artemis/blob/main/tests/smoke-tests/src/test/java/org/apache/activemq/artemis/tests/smoke/console/ConsoleTest.java[ConsoleTest] checks the web console using the https://github.com/SeleniumHQ/selenium[selenium framework].
The tests can be executed using a remote server, local browsers or https://www.testcontainers.org/modules/webdriver_containers[testcontainers].
To use a remote server set the `webdriver.remote.server` property with the URL of the server, ie -Dwebdriver.remote.server=http://localhost:4444/wd/hub To use your local Google Chrome browser download the https://chromedriver.chromium.org/[WebDriver for Chrome] and set the `webdriver.chrome.driver` property with the WebDriver path, ie `-Dwebdriver.chrome.driver=/home/artemis/chromedriver_linux64/chromedriver`.
To use your local Firefox browser download the https://github.com/mozilla/geckodriver/[WebDriver for Firefox] and set the `webdriver.gecko.driver` property with the WebDriver path, ie `-Dwebdriver.gecko.driver=/home/artemis/geckodriver-linux64/geckodriver`.
To use https://www.testcontainers.org/modules/webdriver_containers[testcontainers] install docker.

== Keys for writing good tests

=== Use logger.debug

* Please use `logger.debug` instead of `logger.info`.
+
On your classes, import the following:
+
[,java]
----
public class MyTest {
private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger($CLASS_NAME$.class);

     @Test
     public void test() {
            log.debug("Log only what you need please!");
     }
}
----

* Please do not use `System.out.println()`

As a general rule, only use `System.out` if you really intend an error to be on the reporting.
Debug information should be called through `logger.debug`.

=== Avoid leaks

An important task for any test-case is to clean up all the resources it creates when it runs.
This includes the server instance itself and any resources created to connect to it (e.g. instances of `ServerLocator`, `ClientSessionFactory`, `ClientSession`, etc.).
This task is typically completed in the test's `tearDown()` method.
However, `ActiveMQTestBase`  (and other classes which extend it) simplifies this process.
As https://github.com/apache/activemq-artemis/blob/main/tests/integration-tests/src/test/java/org/apache/activemq/artemis/tests/integration/SimpleTest.java[`org.apache.activemq.artemis.tests.integration.SimpleTest`] demonstrates, there are several methods you can use when creating your test which will ensure proper clean up _automatically_ when the test is torn down.
These include:

* All the overloaded `org.apache.activemq.artemis.tests.util.ActiveMQTestBase.createServer(..)` methods.
If you choose _not_ to use one of these methods to create your `ActiveMQServer` instance then use the `addServer(ActiveMQServer)`  method to add the instance to the test-suite's internal resource ledger.

* Methods from `org.apache.activemq.artemis.tests.util.ActiveMQTestBase` to create a `ServerLocator` like  `createInVMNonHALocator` and `createNettyNonHALocator`.
If you choose _not_ to use one of these methods then use  `addServerLocator(ServerLocator)` to add the locator to the test-suite's internal resource ledger.

* `org.apache.activemq.artemis.tests.util.ActiveMQTestBase.createSessionFactory(ServerLocator)` for creating your session factory.
If you choose _not_ to use this method then use `org.apache.activemq.artemis.tests.util.ActiveMQTestBase.addSessionFactory` to add the factory to the test-suite's internal resource ledger.

=== Create configurations

There are numerous methods in `org.apache.activemq.artemis.tests.util.ActiveMQTestBase` to create a configuration.
These methods are named like create&#42;Config(..).
Each one creates a slightly different configuration but there is a lot of  overlap between them.

In any case, `org.apache.activemq.artemis.core.config.Configuration` is a https://en.wikipedia.org/wiki/Fluent_interface[_fluent_] interface so it's easy to customize however you need.

=== Look at other test-cases

If you need ideas on how to configure something or test something try looking through the test-suite at other test-cases which may be similar.
This is one of the best ways to learn how the test-suite works and how you can leverage the testing infrastructure to test your particular case.