I am in a process of writing web application that uses Play framework (2.1.1 version).
I wrote my first, very simple, controller and I wanted to unit test it.
The thing is, because Play controllers are all static I am wondering what is the correct way to mock out dependencies, for example, lets take some MyService:
private static MyService myService = new MyServiceImpl();
I am using this kind of initialization in my application to deliver controller dependencies.
Now, if I would want to mock out my dependency I could create static method that sets the myService field to mocked out implementation of MyService.
Is this the way it is done in play framework application that is written in Java? Or maybe there is some more "idiomatic" way to do this kind of thing in Play framework.
How to achieve something like that is documented on http://www.playframework.com/documentation/2.1.1/JavaInjection .
On https://github.com/guillaumebort/play20-spring-demo is a demo of a Play Spring project.
With play.Play.isTest() you can check if you are in test mode. It is documented on http://www.playframework.com/documentation/api/2.1.1/java/play/Play.html .
Related
I have a simple Spring Boot application which reads from Kafka topic and persists the messages to some cache.
I would like to add an integration test, which would launch my original application, generate some messages from embedded Kafka, and then assert cache contents.
I'm struggling with the "launch my original application" part. How does one do that from Spring Boot integration test?
I've tried doing something like that:
#RunWith(SpringRunner.class)
#SpringBootTest(classes = OriginalApplication.class)
#EmbeddedKafka
public class OriginalApplicationIntegrationTest {
#Test
public void test() throws Exception {
...
}
}
But I see no attempts from Spring to launch my original application.
First of all, there are two possible big "areas" that can go wrong:
Spring Boot Test Setup
Kafka Integration
I believe the question is around the first part so I'll concentrate on that part.
For a quick answer:
When you put a #SpringBootTest annotation, try to use it without parameters at all. And make sure the test is put in a correct package, it matters. This will turn on the automatic resolution of your application.
Now I'll try to briefly explain why its important, the topic is really broad and deep.
Spring Boot checks whether the class annotated with #SpringBootConfiguration (its an annotation put on #SpringBootApplication - which is in turn is on your main class) exists in the same package as the integration test ( Lets say, com.abc.myapp.test is where you put a test)
If not found, it goes one package up and checks there (com.abc.myapp). It will do that again and again till the root package however, lets assume the #SpringBootApplication annotated class is in this package. Notice, If this recursive "search" doesn't find #SpringBootApplication annotated class - the test doesn't start. That's why its important to use the package structure offered by spring boot application.
Now when it finds that class it know which packages should be scanned for beans to start the spring boot application. So it tries to find beans according to practices of spring boot (package com.abc.myapp and beneath). It does it again recursively top-to-bottom this time.
It also runs your starters (autoconfigurations) in this mode.
So, bottom line:
Specifying #SpringBootTest without parameters makes spring boot doing its best to mimic the startup of the real application
If you use it with parameters where you put it a configuration however, it behaves totally differently: Its like saying: "I know where my configurations are, don't try to start everything, here is my configuration, load only it".
A totally different thing, no recursive searches, no auto-configurations startup, etc.
There are several web spring boot java applications. I need to prepare several components for integration testing. My task is to mock all external behaviour such as other projects's components, db calls etc. I found a solution for this using #Profileannotation from spring framework. Here's an example. I can simply create new profile and declare two beans implementations for each profile: one for real usage, for production and another one for integration testing, for stubbing. It would look like this:
#Profile("PROD")
#Configuration
#EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
}
#Profile("MOCK")
#Configuration
#EnableWebSecurity
public class SecurityMockConfig extends WebSecurityConfigurerAdapter {
}
But I have doubts about this design. It looks little bit messy for me. Does this solution considered acceptable for task I have?
Doing this, your mocks and their configuration will be probably packaged with the app running in production.
This seems very odd to me. Would you package your units tests in your deliverd Spring application ? I don't think so. So I would like to say this is a "bad" design since testing dependencies should not be embedded with production code.
However, Spring's documentation about #Profile annotation is using the exemple of environment segregation.
Now, there is a question which needs to be answered: what do you mean by "integration testing" ?
Is this automated integration test ? Or do you want to run your application in different modes for the testing teams ?
Is this is an automated integration test, then there is no reason to use #Profile annotation as automated tests and production code will not be packaged together.
However, if you want your users to make integration tests, then you could create standalone fake project which will be used to simulate the external dependencies you are calling (database, webservices, etc).
Then, #Profile can be used to switch from fake to production mode but only through configuration file: fake profile will make call on your fake external services whereas production will call the real external services.
I am trying to implement integration tests for my Tomcat application, but my issue is that the application is launched separately from the tests so the tests cannot access the application context and neither the database.
My idea is running the tests "within" the running application, so I can #Autowire EntityManager and check for instance the state of the database during testing or even create database entities for testing.
My only idea of doing this is to actually run the application programmatically from the tests as ClassPathXmlApplicationContext("applicationContext.xml") and the access the Context. This would work, but it would be very hard for debugging as we wouldn't be able to use Hotswapping during the testing. Also I guess the server would be stopped as soon as the tests would end. I guess that is not the best and correct solution.
EDIT:
My question was probably unclear, so I will try to clarify.
I have a Tomcat application with Spring and Hibernate. The Spring beans and Hibernate database connection is initialised when the Tomcat application is started. The issue is how to run the tests of the active Spring beans from methods annotated with #Test in src/test/java which are started separately.
Consider this class:
#Component
class MyRepository {
#Autowired
EntityManager em;
#Transactional
public void myMethod(MyEntity entity) {
// do some job with entity
...
em.flush();
}
}
This class will be initialised with Tomcat as a MyRepository bean.
To test it, I cannot just call new MyRepository().myMethod(...) - I need to access the bean. The issue is accessing the bean from the #Test method:
#Test
void testMyRepository() {
Item item = ...
// then use the repository to handle the entity
context.getBean(MyRepository.class).myMethod(item);
// then assert the state of the database
context.getBean(EntityManager.class).find(Item.class, ...) ...
}
I can probably get the context in the initialisation of the tests with
ApplicationContext context = ClassPathXmlApplicationContext("applicationContext.xml");
But it would mean launching the whole application each time the tests are started. The better solution would be if the application could run separately from the tests.
Hope my problem is more clear now.
I would suggest you to use the SpringRunner to start the Spring application context and perform your tests on that running instance. You can customize the context the way it doesn't contain parts you don't want to tests and you can create mocks for components that require some external resources (REST clients and such). Take a look at the Spring docs or Spring Boot docs.
If multiple tests use the same Spring context configuration, the context is started just once and reused. So it's good to have it's configuration in a parent class of your tests. You can autowire any Spring bean into your test and test it.
You can use an in-memory database (such as H2) instead of a production one, so your tests are not dependent on an external infrastructure. To initialize the database, use tools like Flyway or Liquibase. To clear the database before each test, you can use the #Sql annotation.
You can find many examples of projects with such tests, for example my own demo.
If you want to test an external system, I would suggest something like JMeter.
Unfortunately you cant mirror your classes and use them in your tests. Thats a big disadvantage of web services. They always depend on user / machine interaction. With a lot of effort you can extract the functionality of the essential classes or methods and construct test scenarios etc. with jUnit.
The Overview of your possibilities:
special drivers and placeholders
you can use a logger with detailed log-level and file output. Then you created scenarios with the expected result and compare it with your log files.
Capture replay tools. They record your exection and replay them for monitoring.
I can also recommend using Selenium for the frontend tests.
Hope it helped.
I have developed my application and I have a .properties file containing several key-value properties.
In my code I inject said properties like this:
#Value("${services.host}${services.name}")
private String hostname;
I am searching for a way to check every #Value inside of my code so to make sure that every property will be solved at runtime. Something like simulating my application startup.
Is it possible?
Yes, you can create a JUnit test class that loads your application context (just like your production code would) and then execute a test method that verifies that your property values have been injected.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = {AppConfig.class})
public class SpringApplicationTest {
#Autowired
private MyServiceBean serviceBean;
#Test
public void shouldExecuteServiceBean_andProduceExpectedOutcome() {
//TODO test setup
serviceBean.doSomething()
//TODO assert output
}
}
In this example MyServiceBean.java is a class that would be executed from your Main class, so that you are testing the end-to-end logic of your application, including all of the spring dependency injections. Think of it as your "happy path" test scenario. I always include at least one test like this in my projects, to ensure that all of the spring injections are correct and load without error. You wan't to catch the errors before you build and deploy your code.
In the example above AppConfig.java is the same Spring configuration class you use when your code is deployed. You probably want to add another configuration class that overrides some properties/beans specifically for testing only.
#ContextConfiguration(classes = {AppConfig.class, TestConfig.class})
Using a test only class, you can mock out any dependencies that make testing difficult (i.e. use an in-memory database), and also override properties so you can test against "localhost" rather than another service which may or may not be available (so long as you can create an equivalent localhost service in your test setup).
Note: If you are finding it difficult to test your application due to too many dependencies, or external dependencies that cannot be swapped out easily, the pain you are feeling is a good guide to start thinking about how to change your architecture to support ease of testing. You also can just test portions of your application using the above concepts.
I have a Spring Boot application with a REST API. Behind the scenes it uses a vended SDK to call the vendors service. I need to run load tests on my application, but don’t want to call the vendor API and accidentally crash their system during testing.
Is it possible to use Mockito outside of a JUnit test to create a mock for the vendor SDK objects during the normal application runtime?
I figured I would use a profile based configuration beam to enable the mocked object when profile is “performance-test”. But I can find no article/discussion/mention of anyone using Mockito this way and it is making me second guess my approach. Thoughts?
You probably should look for using wiremock or similar software to mock the vendor service, like here: Integration Testing with a fake server
Wiremock is a stub server that you can conveniently start/stop from within JUnit tests. It acts like the remote server when you set up responses. The documentation is really good, I do not want to copy&paste all of it here.
Just a sample:
public class MyTest {
#Rule
public WireMockRule wireMockRule = new WireMockRule(wireMockConfig().dynamicPort().dynamicHttpsPort());
#Test
public void exampleTest() {
stubFor(get(urlEqualTo("/my/resource"))
.willReturn(aResponse()
.withStatus(200)
.withBody("<response>Some content</response>")));
...
verify(postRequestedFor(urlMatching("/my/resource/[a-z0-9]+"))
.withRequestBody(matching(".*<message>1234</message>.*")));
}
}
For loadtest, you would rather run the stub standalone somewhere, and have some script set up the responses.
You probably don't find mention of Mockito because embedding mocks with stub responses into your application is a bad idea and will not help you getting realistic results for load tests (because your responses will be much faster and not pass through serialization/deserialization).
Else also look here:
How to mock remote REST API in unit test with Spring?