Blogument automagic controller wiring with Spring Cloud Contract

content/posts/2021-12-21-autowire-controller-spring-cloud-contract-mockmvc.md

+---
+title: "Autowiring your controllers automagically when using MockMVC and Spring Cloud Contract"
+description: "How to automagically set up your Spring controllers when using MockMVC with Spring Cloud Contract."
+tags:
+- blogumentation
+- spring
+- spring-boot
+- spring-cloud-contract
+license_code: Apache-2.0
+license_prose: CC-BY-NC-SA-4.0
+date: 2021-12-21T12:48:26+0000
+slug: autowire-controller-spring-cloud-contract-mockmvc
+---
+If you're building Spring (Boot) web APIs, you may be using [Spring Cloud Contract](https://spring.io/projects/spring-cloud-contract) for Consumer Driven Contract testing, to ensure that you're not pushing out breaking changes to your APIs.
+
+In the case you're using MockMVC as your HTTP client layer, you may have a base test class defined similar to the documentation:
+
+```java
+// via https://docs.spring.io/spring-cloud-contract/docs/3.1.0/reference/html/getting-started.html#getting-started-first-application-producer
+package com.example.contractTest;
+
+import org.junit.Before;
+
+import io.restassured.module.mockmvc.RestAssuredMockMvc;
+
+public class BaseTestClass {
+
+    @Before
+    public void setup() {
+        RestAssuredMockMvc.standaloneSetup(new FraudController());
+    }
+}
+```
+
+However, you'll note that this requires you adding each controller manually.
+
+You may amend it so you can make each controller `@Autowired` when running under `@SpringBootTest`, so you don't have to construct them all, but it still doesn't really scale nicely in the case you've got quite a few controllers, or that you're adding on extra work each time you want to introduce a new controller.
+
+To make this easier, we can take one of two approaches to automagically wire in all our controllers:
+
+# Using the `WebApplicationContext`
+
+The easiest way of doing this is to hook in an autowired `WebApplicationContext` which will have all the context required for the MockMVC setup:
+
+```java
+import io.restassured.module.mockmvc.RestAssuredMockMvc;
+import org.junit.jupiter.api.BeforeEach;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.web.context.WebApplicationContext;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
+@DirtiesContext
+public class BaseTestClass {
+
+  @Autowired WebApplicationContext context;
+
+  @BeforeEach
+  void setup() {
+    RestAssuredMockMvc.webAppContextSetup(context);
+  }
+}
+```
+
+# Manually configuring beans
+
+Alternatively, we can manually find all the beans that are required and hook them in:
+
+```java
+import io.restassured.module.mockmvc.RestAssuredMockMvc;
+import java.lang.annotation.Annotation;
+import org.junit.jupiter.api.BeforeEach;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.ApplicationContext;
+import org.springframework.stereotype.Controller;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.web.bind.annotation.RestController;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.MOCK)
+@DirtiesContext
+public class BaseTestClass {
+
+  @Autowired private ApplicationContext context;
+
+  @BeforeEach
+  void setup() {
+    RestAssuredMockMvc.standaloneSetup(getBeansOfType(RestController.class, context));
+    RestAssuredMockMvc.standaloneSetup(getBeansOfType(Controller.class, context));
+  }
+
+  private static Object[] getBeansOfType(
+      Class<? extends Annotation> annotationType, ApplicationContext context) {
+    var beans = context.getBeansWithAnnotation(annotationType);
+    var list = beans.values().stream().toList();
+    return list.toArray();
+  }
+}
+```