Writing Integration tests for WSO2 IOT server

Integration testing plays an important role in software testing and it is where we verify that each module of the software functions as it is supposed to be. In WSO2 IOT server, we have written an adequate amount of test cases to cover all the out-of-box functionalities and also provided the extensibility to write customized test cases to cover add-on features. This document will give an introduction on how does the integration tests have been implemented and how can they be extended to cover add-on functionalities.

TestNg has been used as the underlying backbone of the Carbon test automation framework which provides a powerful test execution control mechanism. The framework extensively cater to write test classes with a composition of JMeter and TestNg annotations.

TestNG framework is used to test the functionalities of the IOT server what are mainly known as core CDMF features, such as device enrolment, operations management, notification management etc.

What follows up in this article will guide you through the basics of writing and executing a simple TestNg test case.

Executing testNg test cases

In IOT server source code, you will find all the integration tests residing at the following location of product-iots repository.

product-iots/modules/integration/integration-tests

All the integration test classes are located in src/main subdirectory and the test resources such as testNg.xml file, java keystores and Jmeter scripts are located in the src/resources subdirectory. TestNg engine reads the testng.xml and then executes all the test cases that have been mentioned in the file.

There are several ways to execute the tests. If you want to execute all the test classes at once, you can simply type mvn install in the command line inside the /integration-tests directory. This will execute all the test classes as mentioned in the testng.xml file. If there is only one test class needs to be executed, you can comment out the other test cases from the testng.xml and then run the mvn install command. Optionally, you can execute a particular test class by typing the following command.

mvn surefire:test -Dtest=<name of the test class>
I.e.: mvn surefire:test -Dtest=AndroidEnrollment

Writing a simple test case

Here is a quick overview of some annotations available in TestNG that we will be using in this scenario. You can find a complete list of annotations here.

• @BeforeClass — The annotated method will run only once before the first test method in the current class is invoked. In the context of WSO2, you can use this annotation to obtain security tokens for admin services, configure the server and configure any services.
• @Test — Marks a class or a method as part of the test. Actual implementation of the test goes here. You may programatically invoke the service and retrieve data and assert them.
• @AfterClass — The annotated method will be run only once after all the test methods in the current class have been run. Clear any server configuration made and reset everything to the last configuration to use by the next test in the suit.

Load the integration module to the IDE and create a new package named “SimpleIOTTest” within the tests-integration module. Then create a Java class named SimpleIOTTest and copy the following code. Here, we will be obtaining the licence code for Android Device enrollment and assert whether the response HTTP code is 200.

Then copy the following code snippet in testng.xml resides in resources directory.

Finally, execute the test by simply typing mvn install on the command line inside the tests-integration directory.