Help with JUnit Test for AEM Sling Model

[AadhiraRa]

I'm trying to write unit tests for an AEM Sling Model, but my test is failing. Here's the test I tried:

@RunWith(MockitoJUnitRunner.class)
public class ArticleContentModelTest {

@Rule
public AemContext context = new AemContext();

private ArticleContentModel articleContentModel;

@Before
public void setUp() {
context.create().resource("/content/article", "title", "Sample Article", "body", "This is a sample article body.");
articleContentModel = context.request().adaptTo(ArticleContentModel.class);
}

@test
public void testGetTitle() {
assertEquals("Sample Article", articleContentModel.getTitle());
}

@test
public void testGetBody() {
assertEquals("This is a sample article body.", articleContentModel.getBody());
}
}

I am getting a NullPointerException when trying to assert the title and body in the tests. I have checked that the resource exists, and the ArticleContentModel should have been adapted correctly, but something is wrong.

[muskaanchandwani]

Hello @AadhiraRa 

Problem seems to be here :

articleContentModel = context.request().adaptTo(ArticleContentModel.class);

To fix it, make sure the request is pointing to the correct resource(setResource) before calling adaptTo.

@Before
public void setUp() {
    context.create().resource("/content/article", "title", "Test", "body", "test body");
    Resource resource = context.resourceResolver().getResource("/content/article");
    context.request().setResource(resource);
    articleContentModel = context.request().adaptTo(ArticleContentModel.class);
}

Reference :
https://sling.apache.org/documentation/development/sling-mock.html#slinghttpservletrequest-1

[AadhiraRa]

@muskaanchandwani Thanks for your input! I actually tried the exact approach you suggested - setting the resource explicitly on the request as you mentioned above. Unfortunately, this still results in articleContentModel being null, and the test fails with a NullPointerException.

[SantoshSai · Accepted solution]

Hi @AadhiraRa,

I think the problem is that your Sling model wasn’t properly registered in the test context. Even if the resource is set properly - the adaptation will silently fail.

Try this: 

context.addModelsForClasses(ArticleContentModel.class); // Registers the Sling model
Resource resource = context.resourceResolver().getResource("/content/article");
articleContentModel = resource.adaptTo(ArticleContentModel.class); // Resource-based adaptation

 Hope that help!

[AadhiraRa]

Worked. Thanks!