How to unit test this route builder in camel? - unit-testing

Question

I have the following RouteBuilder Class and I am using dependency injection here. How can I test this route builder? I am using JUnit and camel test classes.
public class TestRoute extends RouteBuilder {
private ServiceConfiguration serviceConfiguration;
public TestRoute(ServiceConfiguration serviceConfiguration) {
this.serviceConfiguration = serviceConfiguration;
}
#Override
public void configure() throws Exception {
String incomingURI = serviceConfiguration.getQueueConfiguration().getURI();
String outgoingURI = serviceConfiguration.getHTTPConfiguration().getURI();
from(incomingURI).
setHeader(Exchange.HTTP_METHOD, constant("PUT")).setHeader(Exchange.CONTENT_TYPE, constant("application/json")).
to(outgoingURI);
}
}
My thoughts:
Creating a testConfiguration extending ServiceConfiguration and pass that. But for that I need to set all the configuration and all because the serviceConfiguration contains many other classes. Can I use Mockito here? What is the correct and easy way to test this?
EDIT: I was using the existing route, so that I don't have to write it again. Looks like that is not the correct way of testing in camel. See my test class. Of course, its not working.
public class RabbitMQRouteTest extends CamelTestSupport {
#Mock
ServiceConfiguration serviceConfiguration;
#Override
protected RouteBuilder createRouteBuilder() throws Exception {
System.out.println("testing");
return new TestRoute(serviceConfiguration);
}
#Test
public void testConfigure() throws Exception {
System.out.println("test");
when(serviceConfiguration.getName()).thenReturn("file://target/inbox");
template.sendBodyAndHeader("file://target/inbox", "Hello World",Exchange.FILE_NAME, "hello.txt");
Thread.sleep(1000);
File target = new File("target/outbox/hello.txt");
assertTrue("File not moved", target.exists());
}
}

Answer 1

As you use #Mock, MockitoAnnotations.initMocks has to be invoked. Additionally, when has also be called before passing the reference to TestRoute:
#Override
protected RouteBuilder createRouteBuilder() throws Exception {
// Initialize serviceConfiguration
MockitoAnnotations.initMocks(this);
when(serviceConfiguration.getName()).thenReturn("file://target/inbox");
return new TestRoute(serviceConfiguration);
}
Alternatively to #Mock and MockitoAnnotations.initMocks, just use:
serviceConfiguration = org.mockito.Mockito.mock(ServiceConfiguration.class);
As when is invoked in createRouteBuilder, serviceConfiguration.getName() always returns the same result for all test methods in the JUnit test class. This could be a problem, if different test methods need different URIs.
Alternatively, you may use adviceWith instead as described here.

Answer 2

Camel has two ways to do the route tests, CamelSpringTestSupport and CamelTestSupport.
CamelSpringTestSupport
You can set the route with some camel-whatever-test.xml to setup the route in Spring configuration xml.
CamelTestSupport
You can set the route with RouteBuilder createRoute. And configure the endpoint with mock components.
Here is some reference link, do not forget to add the dependency jars:
http://camel.apache.org/testing.html

Answer 3

Using mockito makes sense in your case as you only need some small parts of the ServiceConfiguration.
On the other hand it is a bad sign that you need it for setting configuration data. You should check if your configuration can be split up into separate parts or not be used in the RouteBuilder at all. If you have one configuration structure that is used in all parts of your code you create a tight coupling between things that should be separate. If you just need the two properties queue uri and http uri in your routebuilder then consider just having two setters for them.