Testing Reactive data transactions

Using the Spring Test framework, Reactive Stream events can be tested using reactor.test.StepVerifier which contains all the expectations and verifications needed to validate whether the output Stream data complies with the expected result or if the event is not properly composed of the appropriate operators.

Getting ready

Open the same ch07 project and create a number of test cases depicting the use of StepVerifier.

How to do it...

Aside from typical @Test execution, Reactive Stream has a dedicated API called StepVerifier, which can be used to verify if its Stream emission is appropriate for a certain requirement. Let us use the following steps to test Reactive Stream operations:

1. StepVerifier is part of the Reactor Core add-ons so add this dependency to pom.xml:

<dependency> 
    <groupId>io.projectreactor.addons</groupId> 
    <artifactId>reactor-test</artifactId> 
    <version>3.0.7.RELEASE</version> 
     <scope...