I have inherited some code that isn't tested and which loads a resource using a method like :
SomeClass.class.getClassLoader().getResource("somefile");
I've written the following test but there are 0 interactions with the Mock class loader I've created. Can anyone comment on whether this type of test is possible.
public enum SomeClass {
INSTANCE;
public boolean someMethod() {
URL pathToLicense = SomeClass.class.getClassLoader().getResource("somefile");
return false;
}
}
#Test
public void testLicenseWorkflow(){
ClassLoader cl = PowerMockito.mock(ClassLoader.class);
File f = new File("someFile");
assertTrue(f.exists());
logger.info(f.getCanonicalPath() );
when(cl.getResource("somefile")).thenReturn(f.toURL());
verify(cl).getResource("somefile");
assertTrue(SomeClass.INSTANCE.someMethod());
}
Update - Adding a resources via Classloader
I've also tried the following but the someMethod this doens't seem to work either
new URLClassLoader(((URLClassLoader) SomeClass.INSTANCE.getClass().getClassLoader()).getURLs()) {
#Override
public void addURL(URL url) {
super.addURL(url);
logger.info("Calling add URL");
}
}.addURL(f.toURI().toURL());
You are not passing cl to anything. You prepare a mock for a classloader but then proceed to load the resource with another classloader, the one that loaded SomeClass. That is why you have 0 interactions in your mock.
And about your first question, it is possible if somehow you pass your mocked classloader to the method that actually loads the resource. For example, something like
public boolean someMethod(Classloader loader) {
URL pathToLicense = loader.getResource("somefile");
return false;
}
But I have to say that IMO, this test is not very useful, you should be mocking your own components, not java classes. If your goal mocking the classloader is to inject a different file when testing, a better approach is to change your code to receive a Stream and inject a stream connected to the file in production and in testing inject a stream connected to an element in memory.
In other words, resources make for bad testing when they need to be changed at test time
Related
I'm creating tests over existing classes. A number of them have a resource bundle defined as a private final field that's initialized when the object is created via new. I declare a mocked ResourceBundle, use PowerMock's mockStatic method to enable static mocking, and mock the getBundle method to return my mocked ResourceBundle. However, when the constructor runs the code to initialize the field, it simply creates the new resource bundle rather than using the mocked one. I feel like there's one little detail I've missed, but I don't know what it might be.
The reason all this is a problem is this: when I run the test locally, it creates the ResourceBundle object without issue. But when the test is run via our build software (UCBuild), it throws a "can't find resource" exception and the test, and therefore the build, fails.
When I run a test in debug and set a method breakpoint on the constructor, I can see that the "strings" object is created using an actual resource bundle, not the mocked one. I can't for the life of me figure out why.
I've tried declaring the field without initializing it, then using class.getDeclaredField() and Field.setAccesible() to set the resource bundle to point at my mocked one, but of course this just gets overwritten if I run code that re-initializes the field.
The WorkerTest class which tests Worker.java:
#RunWith(PowerMockRunner.class)
#PrepareForTest({FacesContext.class, SaveStatus.class, FacesMessage.class, ResourceBundle.class})
public class WorkerTest {
#Mock
private ResourceBundle mockRB;
#Before
public void setUp() throws Exception {
PowerMockito.mockStatic(ResourceBundle.class);
PowerMockito.when(ResourceBundle.getBundle(anyString())).thenReturn(mockRB);
PowerMockito.when(mockRB.getString(anyString())).thenReturn("tst");
sut = new Worker(); // Breakpoint here to verify mockRB exists
}
...some tests
}
Worker.java:
#Named
#ApplicationScoped
public class Worker implements Serializable {
private static final long serialVersionUID = 4075799125164038417L;
private final ResourceBundle strings = ResourceBundle
.getBundle("com.resources.strings");
public Worker() { //method breakpoint here
}
Thanks in advance
Found the problem. Adding Worker.class to the #PrepareForTest annotation line and everything worked fine.
Trying to write some proper AEM integration tests using the aem-mocks framework. The goal is to try and test a servlet by calling its path,
E.g. an AEM servlet
#SlingServlet(
paths = {"/bin/utils/emailSignUp"},
methods = {"POST"},
selectors = {"form"}
)
public class EmailSignUpFormServlet extends SlingAllMethodsServlet {
#Reference
SubmissionAgent submissionAgent;
#Reference
XSSFilter xssFilter;
public EmailSignUpFormServlet(){
}
public EmailSignUpFormServlet(SubmissionAgent submissionAgent, XSSFilter xssFilter) {
this.submissionAgent = submissionAgent;
this.xssFilter = xssFilter;
}
#Override
public void doPost(SlingHttpServletRequest request, SlingHttpServletResponse response) throws IOException {
String email = request.getParameter("email");
submissionAgent.saveForm(xssFilter.filter(email));
}
}
Here is the corresponding test to try and do the integration testing. Notice how I've called the servlet's 'doPost' method, instead of 'POST'ing via some API.
public class EmailSignUpFormServletTest {
#Rule
public final AemContext context = new AemContext();
#Mock
SubmissionAgent submissionAgent;
#Mock
XSSFilter xssFilter;
private EmailSignUpFormServlet emailSignUpFormServlet;
#Before
public void setup(){
MockitoAnnotations.initMocks(this);
Map<String,String> report = new HashMap<>();
report.put("statusCode","302");
when(submissionAgent.saveForm(any(String.class)).thenReturn(report);
}
#Test
public void emailSignUpFormDoesNotRequireRecaptchaChallenge() throws IOException {
// Setup test email value
context.request().setQueryString("email=test.only#mail.com");
//===================================================================
/*
* WHAT I END UP DOING:
*/
// instantiate a new class of the servlet
emailSignUpFormServlet = new EmailSignUpFormServlet(submissionAgent, xssFilter);
// call the post method (Simulate the POST call)
emailSignUpFormServlet.doPost(context.request(),context.response());
/*
* WHAT I WOULD LIKE TO DO:
*/
// send request using some API that allows me to do post to the framework
// Example:
// context.request().POST("/bin/utils/emailSignUp") <--- doesn't exist!
//===================================================================
// assert response is internally redirected, hence expected status is a 302
assertEquals(302,context.response().getStatus());
}
}
I've done a lot of research on how this could be done (here) and (here), and these links show a lot about how you can set various parameters for context.request() object. However, they just don't show how to finally execute the 'post' call.
What you are trying to do is mix a UT with IT so this won't be easy at least with the aem-mocks framework. Let me explain why.
Assuming that you are able to call your required code
/*
* WHAT I WOULD LIKE TO DO:
*/
// send request using some API that allows me to do post to the framework
// Example:
// context.request().POST("/bin/utils/emailSignUp") <--- doesn't exist!
//===================================================================
Your test will end up executing all the logic in SlingAllMethodsServlet class and its parent classes. I am assuming that this is not what you want to test as these classes are not part of your logic and they already have other UT/IT (under respective Apache projects) to cater for testing requirements.
Also, looking at your code, bulk of your core logic resides in following snipper
String email = request.getParameter("email");
submissionAgent.saveForm(xssFilter.filter(email));
Your UT criteria is already met by the following line of your code:
emailSignUpFormServlet.doPost(context.request(),context.response());
as it covers most of that logic.
Now, if you are looking for proper IT for posting the parameters and parsing them all the way down to doPost method then aem-mocks is not the framework for that because it does not provide it in a simple way.
You can, in theory, mock all the layers from resource resolver, resource provider and sling servlet executors to pass the parameters all the way to your core logic. This can work but it won't benefit your cause because:
Most of the code is already tested via other UT
Too many internal mocking dependencies might make the tests flaky or version dependant.
If you really want to do pure IT, then it will be easier to host the servlet in an instance and access it via HttpClient. This will ensure that all the layers are hit. A lot of tests are done this way but it feels a bit heavy handed for the functionality you want to test and there are better ways of doing it.
Also the reason why context.request().POST doesn't exist is because context.request() for is a mocked state for the sake of testing. You want to actually bind and mock Http.Post operations which needs some way to resolve to your servlet and that is not supported by the framework.
Hope this helps.
I have this production code in my Presenter:
#UiThread
public void tryToReplaceLogo(String emailInitiallySearchedFor, String logoUrl) {
if(isTheEmailWeAskedApiForStillTheSameAsInTheInputField(emailInitiallySearchedFor)){
if (!TextUtils.isEmpty(logoUrl)) {
downloadAndShowImage(logoUrl);
} else {
view.displayDefaultLogo();
}
}
}
public void downloadAndShowImage(String url) {
final Target target = new Target() {
#Override
public void onBitmapLoaded(Bitmap bitmap, Picasso.LoadedFrom from) {
view.displayLogoFromBitmap(bitmap);
}
#Override
public void onBitmapFailed(Drawable errorDrawable) {
}
#Override
public void onPrepareLoad(Drawable placeHolderDrawable) {
}
};
Picasso.with(view.getViewContext()).load(url).resize(150, 150).centerInside().into(target);
}
And this unit test for it:
#Test
public void testDisplayLogoIfValidUrlReturnedAndEmailEnteredIsTheSame() throws Exception {
when(loginView.getUserName()).thenReturn(VALID_EMAIL);
when(loginView.getViewContext()).thenReturn(context);
loginLogoFetcherPresenter.onValidateEmailEvent(createSuccessfulValidateEmailEvent(VALID_EMAIL));
waitForAsyncTaskToKickIn();
verify(loginView).displayLogoFromBitmap((Bitmap) anyObject());
}
However, the displayLogoFromBitmap method is never called so my test fails. I need to mock the Target dependency to invoke the onBitmapLoaded method but I don't know how.
Possibly I need to create a static inner class that implements Target so that I can set a Mocked implementation of that in my tests, but how do I invoke the onBitmapLoaded method on the mock?
EDIT:
I have a setter field for Picasso in my LoginPresenter now. In production, (as I am using AndroidAnnotations), I instantiate it in
#AfterInject
void initPicasso() {
picasso = Picasso.with(context):
}
In my test, I mock Picasso like so:
#Mock
Picasso picasso;
#Before
public void setUp() {
picasso = mock(Picasso.class, RETURNS_DEEP_STUBS);
}
(I don't remember why, but I can't use Mockito 2 at this point. It was some incompatibility with something, I think)
In my test case, I got to this point and I don't know what to do:
#Test
public void displayLogoIfValidUrlReturnedAndEmailEnteredIsTheSame() throws Exception {
when(loginView.getUserName()).thenReturn(VALID_EMAIL);
when(loginView.getViewContext()).thenReturn(context);
when(picasso.load(anyString()).resize(anyInt(), anyInt()).centerInside().into(???)) // What do I do here?
loginLogoFetcherPresenter.onValidateEmailEvent(createSuccessfulValidateEmailEvent(VALID_EMAIL));
waitForAsyncTaskToKickIn();
verify(loginView).displayLogoFromBitmap((Bitmap) anyObject());
}
I need to mock the Target dependency
No; do not mock the system under test. Target is as much a part of that system as anything; you wrote the code for it, after all. Remember, once you mock out a class, you commit to not using its implementation, so trying to mock Target to invoke onBitmapLoaded is missing the point.
What's going on here is that you're passing Target—which is real code you wrote that is worth testing—into Picasso, which is external code you didn't write but do depend on. This makes Picasso the dependency worth mocking, with the caveat that mocking interfaces you don't control can get you into trouble if they change (e.g. a method turns final).
So:
Mock your Picasso instance, and the RequestCreator instance Picasso returns when it loads. RequestCreator implements the Builder pattern, so it's a prime candidate for Mockito 2.0's RETURNS_SELF option or other Builder pattern strategies.
Pass the Picasso instance into your system under test, rather than creating it using Picasso.with. At this point you may not need to stub LoginView.getViewContext(), which is a good thing as your test can interact less with hard-to-test Android system classes, and because you've further separated object creation (Picasso) from business logic.
Use an ArgumentCaptor in your test to extract out the Target method that was called on RequestCreator.into.
Test the state of the system before the async callback returns, if you'd like. It's optional, but it's definitely a state your system will be in, and it's easy to forget to test it. You'd probably call verify(view, never()).onBitmapLoaded(any()).
Call target.onBitmapLoaded yourself. You have the target instance at this point, and it should feel correct to explicitly call your code (that is written in your system-under-test) from your test.
Assert your after-callback state, which here would be verify(view).onBitmapLoaded(any()).
Note that there is an existing test helper called MockPicasso, but it seems to require Robolectric, and I haven't reviewed its safety or utility myself.
I am trying to write unit test for a method which uses an instance of cache as below
public void method(String abc) {
....
....
Cache cache = CacheFactory.getAnyInstance();
....
....
}
I know mocking is the way to resolve this dependency on cache. I am new to mocking and using mockito and not sure on how to pass the mocked cache to the method.
#Mock
Cache cache;
#Test
public void testMethod(){
doReturn(cache).when(CacheFactory.getAnyInstance());
method("abc");
}
The above is what I've tried and got the error.
If you are testing some code path in your application component that calls CacheFactory.getAnyInstance() (such as method("abc")?), then you must ensure that the method gets a reference to the mock Cache another way since you cannot mock a static method on a class (i.e. getAnyInstance() on CacheFactory), at least not without some help from a framework like PowerMock. For example...
public class ExampleApplicationComponent {
public void methodUnderTest(String value) {
...
Cache hopefullyAMockCacheWhenTesting = CachFactory.getAnyInstance();
...
// do something with the Cache...
}
}
Of course, this will fail. So you need to restructure your code a bit...
public class ExampleApplicationComponent {
public void methodUnderTest(String value) {
...
Cache cache = fetchCache();
...
// do something with the (mock) Cache...
}
Cache fetchCache() {
return CacheFactory.getAnyInstance();
}
}
Then in you test case in your test class...
public class ExampleApplicationComponentTest {
#Mock
private Cache mockCache;
#Test
public void methodUsesCacheProperly() {
ExampleApplicationComponent applicationComponent =
new ExampleApplicationComponent() {
Cache fetchCache() {
return mockCache;
}
};
applicationComponent.method("abc");
// assert appropriate interactions were performed on mockCache
}
}
So as you can see, you can override the fetchCache() method in your anonymous ExampleApplicationComponent subclass within you test case to return the mock Cache. Also note, the fetchCache() method was deliberately made "package-private" to limit it's accessibility to primarily the test class (since test classes usually and should reside in the same package as the class under test). This prevents the fetchCache method from escaping and becoming part of your API. While other classes in the same package can access the method of an instance of the ExampleApplicationComponent class, you at least retrain control over that usage (and of course there is not substitute for good documentation).
To see other examples of this in practice, have a look as Spring Data GemFire's CacheFactoryBeanTest class (for instance, and specifically), which does exactly what I described above using Mockito.
Hope this helps.
Cheers!
-John
I was ble to do this with the help of PowerMockito below is the code
mockStatic(CacheFactory.class);
when(CacheFactory.getAnyInstance()).thenReturn(cache);
method("abc");
verifyStatic();
CacheFactory.getAnyInstance();
Im reading "The art of unit testing" atm and im having some issues with using properties to pass in an interface. The book states the following: "If you want parameters to be optional, use property getters/setters, which is a better way of defining optional parameters than adding different constructors to the class for each dependency."
The code for the property example is as follows:
public class LogAnalyzer
{
private IExtensionManager manager;
public LogAnalyzer ()
{
manager = new FileExtensionManager();
}
public IExtensionManager ExtensionManager
{
get { return manager; }
set { manager = value; }
}
public bool IsValidLogFileName(string fileName)
{
return manager.IsValid(fileName);
}
}
[Test]
Public void
IsValidFileName_NameShorterThan6CharsButSupportedExtension_ReturnsFalse()
{
//set up the stub to use, make sure it returns true
...
//create analyzer and inject stub
LogAnalyzer log = new LogAnalyzer ();
log.ExtensionManager=someFakeManagerCreatedEarlier;
//Assert logic assuming extension is supported
...
}
When/how would i use this feature?? The only scenario i can think of (This is probably wrong!) is if i had two methods in one class,
Method1() retrieves the database connection string from the config file and contains some form of check on the retrieved string.
Method2() then connect to the database and returns some data. The check here could be that that returned data is not null?
In this case, to test Method1() i could declare a stub that implements the IExtensionManager Interface, where the stub has a string which should pass any error checks i have in method1().
For Method2(), i declare a stub which implements the interface, and declare a datatable which contains some data, in the stub class. id then use the properties to assign this to the private manager variable and then call Method2?
The above may be complete BS, so if it is, id appreciate it if someone would let me know and ill remove it.
Thanks
Property injection used to change object's behavior after it was created.
BTW your code is tight coupled to FileExtensionManager, which is concrete implementation of IExtensionManager. How you are going to test LogAnalyzer with default manager? Use constructor injection to provide dependencies to your objects - this will make them testable:
public LogAnalyzer (IExtensionManager manager)
{
this.manager = manager();
}