Base test class for integration testing imports base configuration with component scan that includes almost all packages. In one test class I want to override some beans with Mocs, but this inner configuration is scanned and overrides beans for all tests. Is there some way to avoid this?
I've found the way I like mocking beans with by essentially having a separate MockObjectsConfig class with the mock objects I want using the standard Spring Context Configuration, and then import it alongside my real test config. You can also annotate your mock bean with #Profile and test with #ActiveProfiles if you need to prevent a conflict there.
#Configuration
#Profile("!test")
public class MyRealConfigClass {
#Bean
public YetAnotherClass yetAnotherClass() {
return new YetAnotherClass();
}
}
#Configuration
#Profile("test")
public class MockObjectsConfig {
#Bean
public YetAnotherClass yetAnotherClass() {
Mockito.mock(YetAnotherClass.class); // and add any thenReturns, answers, etc. here
}
}
Then include it in your test like so:
#RunWith(SpringRunner.class)
#ContextConfiguration(classes = { MyRealConfigClass.class, MockObjectsConfig.class)
#ActiveProfiles({"test"})
public class MyJunitTest {
#Autowired
private RestController restController;
}
Then your mock bean will be used and not the real one from the production config.
I would like to be able to use a bean via auto-wiring and without having to directly use an ApplicationContext. Below is a dummy example of what I would like to be able to do.
Configuration Class
#Configuration
public class CoffeeConfig
{
#Bean
public CoffeeMachine provideCoffeeMachine()
{
return new CoffeeMachine(provideCoffeeBean());
}
#Bean
public CoffeeBean provideCoffeeBean()
{
return new CoffeeBean(Type.BEST);
}
}
Coffee Shop Class
#Component
public class CoffeeShop
{
#Autowired
private CoffeeMachine cMachine;
public void pourCoffee()
{
System.out.print("Pouring cup of coffee: " + cMachine.pour(Amount.8OZ));
}
}
In order to solve this, I have been reading through spring documentation and spring tutorials. The problem is, I haven't seen anyone attempt to illustrate how to do something as simple as this, and when they do, they end up resorting to using an application context. That being said, I know that if I am running unit tests with Spring, I can do the following:
Test Class
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes=CoffeeConfig.class, loader=AnnotationConfigContextLoader.class)
public class SpringIOCTests
{
#Autowired
public CoffeeMachine cMachine;
#Test
public void influxDevTest()
{
assertEquals(Type.BEST, cMachine.getBeans());
}
}
The way this configures leads me to believe that using auto-wiring in such a way should be attainable in the actual application instead of using these test-only dependencies such as the ContextConfiguration. I should also note that this unit test does pass.
Does Spring offer a methodology in which one can auto-wire dependencies in a nice and clean way avoiding the direct use of an application contexts?
For my Spring-Boot app I provide a RestTemplate though a #Configuration file so I can add sensible defaults(ex Timeouts). For my integration tests I would like to mock the RestTemplate as I dont want to connect to external services - I know what responses to expect. I tried providing a different implementation in the integration-test package in the hope that the latter will override the real implementation , but checking the logs it`s the other way around : the real implementation overrides the test one. How can I make sure the one from the TestConfig is the one used?
This is my config file :
#Configuration
public class RestTemplateProvider {
private static final int DEFAULT_SERVICE_TIMEOUT = 5_000;
#Bean
public RestTemplate restTemplate(){
return new RestTemplate(buildClientConfigurationFactory());
}
private ClientHttpRequestFactory buildClientConfigurationFactory() {
HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory();
factory.setReadTimeout(DEFAULT_SERVICE_TIMEOUT);
factory.setConnectTimeout(DEFAULT_SERVICE_TIMEOUT);
return factory;
}
}
Integration test:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = TestConfiguration.class)
#WebAppConfiguration
#ActiveProfiles("it")
public abstract class IntegrationTest {}
TestConfiguration class:
#Configuration
#Import({Application.class, MockRestTemplateConfiguration.class})
public class TestConfiguration {}
And finally MockRestTemplateConfiguration
#Configuration
public class MockRestTemplateConfiguration {
#Bean
public RestTemplate restTemplate() {
return Mockito.mock(RestTemplate.class)
}
}
Since Spring Boot 1.4.x there is an option to use #MockBean annotation to fake Spring beans.
Reaction on comment:
To keep context in cache do not use #DirtiesContext, but use #ContextConfiguration(name = "contextWithFakeBean") and it will create separate context, while it will keep default context in cache. Spring will keep both (or how many contexts you have) in cache.
Our build is this way, where most of the tests are using default non-poluted config, but we have 4-5 tests that are faking beans. Default context is nicely reused
1.
You can use #Primary annotation:
#Configuration
public class MockRestTemplateConfiguration {
#Bean
#Primary
public RestTemplate restTemplate() {
return Mockito.mock(RestTemplate.class)
}
}
BTW, I wrote blog post about faking Spring bean
2.
But I would suggest to take a look at Spring RestTemplate testing support. This would be simple example:
private MockRestServiceServer mockServer;
#Autowired
private RestTemplate restTemplate;
#Autowired
private UsersClient usersClient;
#BeforeMethod
public void init() {
mockServer = MockRestServiceServer.createServer(restTemplate);
}
#Test
public void testSingleGet() throws Exception {
// GIVEN
int testingIdentifier = 0;
mockServer.expect(requestTo(USERS_URL + "/" + testingIdentifier))
.andExpect(method(HttpMethod.GET))
.andRespond(withSuccess(TEST_RECORD0, MediaType.APPLICATION_JSON));
// WHEN
User user = usersClient.getUser(testingIdentifier);
// THEN
mockServer.verify();
assertEquals(user.getName(), USER0_NAME);
assertEquals(user.getEmail(), USER0_EMAIL);
}
More examples can be found in my Github repo here
The Problem in your configuration is that you are using #Configuration for your test configuration. This will replace your main configuration. Instead use #TestConfiguration which will append (override) your main configuration.
46.3.2 Detecting Test Configuration
If you want to customize the primary configuration, you can use a
nested #TestConfiguration class. Unlike a nested #Configuration class,
which would be used instead of your application’s primary
configuration, a nested #TestConfiguration class is used in addition
to your application’s primary configuration.
Example using SpringBoot:
Main class
#SpringBootApplication() // Will scan for #Components and #Configs in package tree
public class Main{
}
Main config
#Configuration
public void AppConfig() {
// Define any beans
}
Test config
#TestConfiguration
public void AppTestConfig(){
// override beans for testing
}
Test class
#RunWith(SpringRunner.class)
#Import(AppTestConfig.class)
#SpringBootTest
public void AppTest() {
// use #MockBean if you like
}
Note: Be aware, that all Beans will be created, even those that you override. Use #Profile if you wish not to instantiate a #Configuration.
#MockBean and bean overriding used by the OP are two complementary approaches.
You want to use #MockBean to create a mock and forget the real implementation : generally you do that for slice testing or integration testing that doesn't load some beans which class(es) you are testing depend on and that you don't want to test these beans in integration.
Spring makes them by default null, you will mock the minimal behavior for them to fulfill your test.
#WebMvcTest requires very often that strategy as you don't want to test the whole layers and #SpringBootTest may also require that if you specify only a subset of your beans configuration in the test configuration.
On the other hand, sometimes you want to perform an integration test with as many real components as possible, so you don't want to use #MockBean but you want to override slightly a behavior, a dependency or define a new scope for a bean, in this case, the approach to follow is bean overriding :
#SpringBootTest({"spring.main.allow-bean-definition-overriding=true"})
#Import(FooTest.OverrideBean.class)
public class FooTest{
#Test
public void getFoo() throws Exception {
// ...
}
#TestConfiguration
public static class OverrideBean {
// change the bean scope to SINGLETON
#Bean
#Scope(ConfigurableBeanFactory.SINGLETON)
public Bar bar() {
return new Bar();
}
// use a stub for a bean
#Bean
public FooBar BarFoo() {
return new BarFooStub();
}
// use a stub for the dependency of a bean
#Bean
public FooBar fooBar() {
return new FooBar(new StubDependency());
}
}
}
With #Primary annotation, Bean overriding works with Spring Boot 1.5.X but fails with Spring Boot 2.1.X it throw error:
Invalid bean definition with name 'testBean' defined in sample..ConfigTest$SpringConfig:..
There is already .. defined in class path resource [TestConfig.class]] bound
Please add below properties= which will instruct Spring explicitly to allow overriding, it is self explainatory.
#SpringBootTest(properties = ["spring.main.allow-bean-definition-overriding=true"])
UPDATE: You can add the same property in application-test.yml (file name depend upon what test profile name you are tests with)
Getting a little deeper into it, see my second answer.
I solved the Problem using
#SpringBootTest(classes = {AppConfiguration.class, AppTestConfiguration.class})
instead of
#Import({ AppConfiguration.class, AppTestConfiguration.class });
In my case the Test is not in the same package as the App. So I need to specify the AppConfiguration.class (or the App.class) explicit. If you use the same package in the test, than I guess you could just write
#SpringBootTest(classes = AppTestConfiguration.class)
instead of (not working)
#Import(AppTestConfiguration.class );
It is pretty wired to see that this is so different. Maybe some one can explain this. I could not find any good answers until now. You might think, #Import(...) is not picked up if #SpringBootTestsis present, but in the log the overriding bean shows up. But just the wrong way around.
By the way, using #TestConfiguration instead #Configuration also makes no difference.
I´ve declared an inner configuration class within my test because I wanted to overwrite just a single method
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
public class FileNotificationWebhookTest{
public static class FileNotificationWebhookTestConfiguration {
#Bean
#Primary
public FileJobRequestConverter fileJobRequestConverter() {
return new FileJobRequestConverter() {
#Override
protected File resolveWindowsPath(String path) {
return new File(path);
}
};
}
}
}
However,
Declaring the configuration in #SpringBootTest did not work:
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,classes = {FileNotificationWebhookTest.FileNotificationWebhookTestConfiguration.class})
or annotating the test configuration with #Configuration did not work:
#Configuration
public static class FileNotificationWebhookTestConfiguration {
}
and was leading to
Caused by: org.springframework.context.ApplicationContextException:
Unable to start web server; nested exception is
org.springframework.context.ApplicationContextException: Unable to
start ServletWebServerApplicationContext due to missing
ServletWebServerFactory bean.
What did work for me ( contrary to some other posts here) was using #Import
#SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
#Import(FileNotificationWebhookTest.FileNotificationWebhookTestConfiguration.class)
class FileNotificationWebhookTest {
}
Using Spring: 5.3.3 with Spring-Boot-Starter: 2.4.2
#MockBean creates Mockito mock instead of production build.
If you do not want to use Mockito, but provide a replacement in some other way (i.e. by disabling some features of bean with feature toggles), I suggest using combination of #TestConfiguration (since Spring Boot 1.4.0) and #Primary annotation.
#TestConfiguration will load your default context and apply your #TestConfiguration piece in addition to it. Adding #Primary will force your mocked RestTemplate to be injected to it's dependents.
See simplified example below:
#SpringBootTest
public class ServiceTest {
#TestConfiguration
static class AdditionalCfg {
#Primary
#Bean
RestTemplate rt() {
return new RestTemplate() {
#Override
public String exec() {
return "Test rest template";
}
};
}
}
#Autowired
MyService myService;
#Test
void contextLoads() {
assertThat(myService.invoke()).isEqualTo("Test rest template");
}
}
This is super weird.
In my case, (Spring Boot 2.6.7), I could simply #Import MyTestConfiguration containing a custom #Primary #Bean into my #SpringBootTest, and everything worked.
Right until I needed to explicitly name my bean.
Then I suddenly had to resort to
#SpringBootTest(
properties = ["spring.main.allow-bean-definition-overriding=true"],
classes = [MyTestConfig::class],
)
Check this answer along with others provided in that thread.
It's about overriding bean in Spring Boot 2.X, where this option was disabled by default. It also has some ideas about how to use Bean Definition DSL if you decided to take that path.
The simplest solution I found was to set this property in application.properties:
spring.main.allow-bean-definition-overriding=true
This will enable overriding of beans.
Next, create a configuration class in test, and annotate your bean with:
#Bean
#Primary
This way, this bean will override your usual bean when running tests.
i have a spring boot application. sometimes i need to launch long running report generation. the easiest way was to create an #IntegrationTest to use spring's #Autowire:
#RunWith(SpringJUnit4ClassRunner.class)
#WebAppConfiguration
#SpringApplicationConfiguration(classes=Application.class)
#IntegrationTest
public class ReportGenerationTest {
#Autowired MyService myService;
#Value("classpath:/test.txt") Resource testData; //it's in test, not in src
#Test
public void generate_report() {
report(myService, testData);
}
}
it works perfectly. but i don't want it to be run with every build. i also don't want to add/remove #Ignore as sooner or later someone will accidentally commit it without #Ignore and i don't want to do any code editing just to run reports
ideally i would like it to be a main method run on demand. but how can i manually create a spring context for the src service and test resources?
i need something like:
public class MyReport {
public static void main(String[] args) {
ReportGenerationTest reportGenerator = getAutowiredInstanceFromSpring();
reportGenerator.generate_report();
}
}
In my application I initialize a property before spring application startup as follows:
MapLookup.setMainArguments(new String[] {"logging.profile", profile}); //from args
SpringApplication.run(source, args);
(just for reference: it is used for log4j2 logging, which must be set before spring starts to initialize).
Now I want to run an #IntegrationTest, but use the same logging configuration. Obviously I cannot use the code above, as a JUnit test is not executed using SpringApplication.run.
So, how could I initialize code before a #RunWith(SpringJUnit4ClassRunner.class) starts?
Note: BeforeClass does not work as this is executed after spring context startup.
You can run the initialization in a static initializer. Static initializer will run after JUnit loads the test class and before JUnit reads any annotations on it.
Alternatively you can extend SpringJUnit4ClassRunner with your own Runner initialize in it first and then run SpringJUnit4ClassRunner
I had a slightly different problem. I need to deploy something to my service after the Spring context is loaded. Solution use a custom config class for the test and run the deployment within a #PostConstruct Method.
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = TestConfig.class, loader = AnnotationConfigContextLoader.class)
public class JunitTest {
#Configuration
#ComponentScan(basePackages = { "de.foo })
public static class TestMConfig {
#Autowired
private DeploymentService service;
#PostConstruct
public void init() {
service.deploy(...);
}
}
#Test
public void test() {
...
}
}
Maybe this helps, someone, sometime, somewhere ;)