# Pact Spring/JUnit runner
## Overview
Library provides ability to play contract tests against a provider using Spring & JUnit.
This library is based on and references the JUnit package, so see [junit provider support](pact-jvm-provider-junit) for more details regarding configuration using JUnit.
Supports:
- Standard ways to load pacts from folders and broker
- Easy way to change assertion strategy
- Spring Test MockMVC Controllers and ControllerAdvice using MockMvc standalonesetup.
- MockMvc debugger output
- Multiple @State runs to test a particular Provider State multiple times
- **au.com.dius.pact.provider.junit.State** custom annotation - before each interaction that requires a state change,
all methods annotated by `@State` with appropriate the state listed will be invoked.
## Example of MockMvc test
```java
@RunWith(RestPactRunner.class) // Custom pact runner, child of PactRunner which runs only REST tests
@Provider("myAwesomeService") // Set up name of tested provider
@PactFolder("pacts") // Point where to find pacts (See also section Pacts source in documentation)
public class ContractTest {
//Create an instance of your controller. We cannot autowire this as we're not using (and don't want to use) a Spring test runner.
@InjectMocks
private AwesomeController awesomeController = new AwesomeController();
//Mock your service logic class. We'll use this to create scenarios for respective provider states.
@Mock
private AwesomeBusinessLogic awesomeBusinessLogic;
//Create an instance of your controller advice (if you have one). This will be passed to the MockMvcTarget constructor to be wired up with MockMvc.
@InjectMocks
private AwesomeControllerAdvice awesomeControllerAdvice = new AwesomeControllerAdvice();
//Create a new instance of the MockMvcTarget and annotate it as the TestTarget for PactRunner
@TestTarget
public final MockMvcTarget target = new MockMvcTarget();
@Before //Method will be run before each test of interaction
public void before() {
//initialize your mocks using your mocking framework
MockitoAnnotations.initMocks(this);
//configure the MockMvcTarget with your controller and controller advice
target.setControllers(awesomeController);
target.setControllerAdvice(awesomeControllerAdvice);
}
@State("default", "no-data") // Method will be run before testing interactions that require "default" or "no-data" state
public void toDefaultState() {
target.setRunTimes(3); //let's loop through this state a few times for a 3 data variants
when(awesomeBusinessLogic.getById(any(UUID.class)))
.thenReturn(myTestHelper.generateRandomReturnData(UUID.randomUUID(), ExampleEnum.ONE))
.thenReturn(myTestHelper.generateRandomReturnData(UUID.randomUUID(), ExampleEnum.TWO))
.thenReturn(myTestHelper.generateRandomReturnData(UUID.randomUUID(), ExampleEnum.THREE));
}
@State("error-case")
public void SingleUploadExistsState_Success() {
target.setRunTimes(1); //tell the runner to only loop one time for this state
//you might want to throw exceptions to be picked off by your controller advice
when(awesomeBusinessLogic.getById(any(UUID.class)))
.then(i -> { throw new NotCoolException(i.getArgumentAt(0, UUID.class).toString()); });
}
}
```
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