How to Unit Test in Z2¶

The Z2 Jupiter of z2-base.base allow to run in-system tests on z2, from anywhere where you can run JUnit tests. To learn more about the JUnit testing framework, please visit http://www.junit.org.

In-system tests are ordinary unit tests that run within the server environment. Running tests within the running environment is also called integration testing.

Standard JUnit tests run in an environment that often has little to do with the tested code's "native" environment, other than seeing the same types. Anything else, database connectivity, domain test data, component and naming abstractions (e.g. JNDI) need to be firstly abstracted out from the tested code and secondly mocked, that is, simulated one way or the other, into the test assembly of things.

While that has the advantage of a defined, clean-room test bed, for higher-level components this can become unreasonable and assuring the correctness of the mocked up environment becomes a testing issue on its own.

The z2 Jupiter feature is built on the JUnit 5 API that succeeded the JUnit 4 API that is the underlying foundation of the previously promoted z2Unit feature (see How to z2Unit). It is recommended that you use the z2 Jupiter implementation today starting with z2 Version 2.9.

The foundation Z2 Jupiter is the Z2 Jupiter Test Engine implementation that delegate test discovery and test execution to a running z2 server runtime. That is, although JUnit believes to run a locally defined test class, the actual test runs in another process, running the methods and reporting results corresponding to the structure of the local test implementation (which matches its server-side equivalent).

Using z2 Jupiter¶

Using z2 Jupiter is as easy as referencing the module com.zfabrik.dev.z2jupiter from the test module and adding one more annotation to your test class: Z2JupiterTestable.

Z2 Jupiter uses itself for testing. You can see a simple "Hello World" test at z2-base:source:base|com.zfabrik.dev.z2jupiter/java/src.test/com/zfabrik/dev/z2jupiter/test/HelloZ2JupiterTest.java:

package com.zfabrik.dev.z2jupiter.test;

import org.junit.jupiter.api.Test;

import com.zfabrik.dev.z2jupiter.Z2JupiterTestable;
import com.zfabrik.dev.z2jupiter.impl.Z2JupiterImpl;

@Z2JupiterTestable(componentName = Z2JupiterImpl.MODULE_NAME)
public class HelloZ2JupiterTest {

    @Test
    public void helloZ2Jupiter() {
        System.err.println("Hello Z2 Jupiter");
    }
}

Check out more test examples in z2-base:source:base|com.zfabrik.dev.z2jupiter/java/src.test/com/zfabrik/dev/z2jupiter/test .

If you want to use Z2 Jupiter in your projects for tests implemented under java/src.test, make sure to have the framework referenced in java/z.properties like this:

java.testReferences=\
    com.zfabrik.dev.z2jupiter,\

To see how this works in Eclipse¶

1. Follow the "Up in 5 minutes" trail Step_2_-_Install_and_run_in_5_minutes to make sure you understand how to setup z2 and Eclipse.
2. Create a Z2 Java project my_tests in your Eclipse workspace. Make sure it is armed.
3. Add a test reference to com.zfabrik.dev.z2jupiter to your Java component, say my_tests/java.
4. Create a test class in src.test of your Java component like the following:
   

   package mytest;
   
   import org.junit.jupiter.api.Test;
   
   import com.zfabrik.dev.z2jupiter.Z2JupiterTestable;
   
   @Z2JupiterTestable(componentName="my_tests/java")
   public class AZ2UnitTest {
   
       @Test
       public void someTestMethod() {  
           System.out.println("Hello z2Unit");
       }
   }
   

5. Resolve using the Eclipsoid plugin (see above)
6. Right-click and choose Run-As / JUnit Test

Using and Configuring z2Unit outside of the IDE¶

Note that resolving the dependencies and synchronizing the runtime is an important prerequisite to running a z2Unit Unit Test class. You need to have all dependencies of the test class resolved so that JUnit can resolve the test class locally (although all the action will happen elsewhere) and you need to have synchronized so that the matching definitions are found on the server side.

If you want to automate tests and cannot rely on the Eclipsoid to have a suitable class path, you should use the com.zfabrik.dev.util/jarRetriever tool to retrieve all required dependencies. In that case, you can run z2Unit tests just as any unit tests also from an ANT script for example. A typical application is to run z2Unit integration tests as part of your test automation effort.

The execution of a z2Unit test requires the test client, which is the local JUnit runtime invoked by ANT (or your IDE as above) invoking the Z2UnitTestRunner, to connect via HTTP to the Z2 application server. If you run tests on the same operating system instance the application runs on, this works by default by reaching out to localhost. If your application server is on a different machine though, you will want to configure that accordingly.

For example, you could define a different z2unitUrl when configuring the Z2UnitTest annotation.

That is not practical when running test automatically however, as you would not want to change application code for that purpose.

Instead you can specify essentially the same configuration that the Z2UnitTest annotation holds by setting any of the system properties shown belown during test execution. For example in your ANT script.

Alternatively you can specify these configuration settings by putting a file called, by default, z2unit.properties on the classpath of the Unit Test Runner (i.e. the ANT test execution classpath for example). The name of the configuration file can be overwritten in a test specific way by setting in on the Z2UnitTest annotation on the test class, in case you need many different configurations.

Properties that control the behavior of the Z2UnitTestRunner, and that may be specified as system properties or via the configuration file are shown in the following table:

Property Name	Property Meaning
z2unit.className	Name of the test class. As a result, z2Unit will report test execution events on that class which may not match the structure of the client side class.
z2unit.componentName	Name of the java component that contains the test class. A short form may be used for java components "/java".
z2unit.z2unitUrl	URL to send the test request to. Defaults to http://localhost:8080/z2unit/run.

Using other Unit Test Runners¶

Using the Z2UnitTest annotation, a test can be configured to run with a non-standard unit test runner. That is useful for example, if your test is actually a test suite or something special like a Spock test. See Sample-groovy-in-Z2 for an example of the latter.

Furthermore, a unit test can be configured to have some runtime dependencies in Z2, i.e. components that should be prepared prior to the test execution. That is extremely useful, if the test depends on a configured Spring application context for example. In the latter case, the test could even use Spring configuration annotations (which is what we typically do).

References¶

Read on in the Javadocs for more details.