title: Testing that custom Spring Boot AutoConfiguration is valid
body: <p>I've decided to write quite a trivial test to check that my Spring Boot auto-configuration works - all the needed beans are created along with their dependencies.</p>
  
  <p>AutoConfiguration is:</p>
  
  <pre><code>package org.project.module.autoconfigure;
  
  import org.project.module.SomeFactory;
  import org.project.module.SomeProducer;
  import org.project.module.SomeServiceClient;
  import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
  import org.springframework.context.annotation.Bean;
  import org.springframework.context.annotation.ComponentScan;
  import org.springframework.context.annotation.Configuration;
  
  /**
   * Spring Boot simple auto-configuration.
   *
   * @author istepanov
   */
  @Configuration
  @ComponentScan("org.project.module.support")
  public class SomeAutoConfiguration {
  
      @Bean
      @ConditionalOnMissingBean
      public SomeFactory someFactory() {
          return new SomeFactory();
      }
  
      @Bean
      @ConditionalOnMissingBean
      public SomeServiceClient someServiceClient() {
          return new SomeServiceClient();
      }
  
      @Bean
      @ConditionalOnMissingBean
      public SomeProducer someProducer() {
          return new SomeProducer();
      }
  }
  </code></pre>
  
  <p>And test is:</p>
  
  <pre><code>package org.project.module.autoconfigure;
  
  import org.project.module.SomeFactory;
  import org.project.module.SomeProducer;
  import org.project.module.SomeServiceClient;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.boot.test.context.SpringBootTest;
  import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  /**
   * Tests for {@code SomeAutoConfiguration}.
   *
   * @author istepanov
   */
  @RunWith(SpringJUnit4ClassRunner.class)
  @SpringBootTest(classes = {SomeAutoConfiguration.class}, webEnvironment = SpringBootTest.WebEnvironment.NONE)
  public class SomeAutoConfigurationTest {
  
      @Autowired
      private SomeFactory someFactory;
      @Autowired
      private SomeServiceClient someServiceClient;
      @Autowired
      private SomeProducer someProducer;
  
      @Test
      public void someFactory_isNotNull() {
          assertThat(someFactory).isNotNull();
      }
  
      @Test
      public void someServiceClient_isNotNull() {
          assertThat(someServiceClient).isNotNull();
      }
  
      @Test
      public void someProducer_isNotNull() {
          assertThat(someProducer).isNotNull();
      }
  }
  </code></pre>
  
  <p>But actually test fails with exception - dependent beans, which are expected to be loaded with <code>@ComponentScan</code>, are actually missing:</p>
  
  <pre><code>java.lang.IllegalStateException: Failed to load ApplicationContext
      at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
      at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:83)
      at org.springframework.boot.test.autoconfigure.AutoConfigureReportTestExecutionListener.prepareTestInstance(AutoConfigureReportTestExecutionListener.java:49)
      at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287)
      at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:289)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
      at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
      at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
      at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
      at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
      at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
      at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
      at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
      at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
      at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
      at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
      at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:68)
  Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'someFacade': Unsatisfied dependency expressed through method 'setSomeMetrics' parameter 0: Error creating bean with name 'someMetrics': Unsatisfied dependency expressed through method 'setCounterService' parameter 0: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'someMetrics': Unsatisfied dependency expressed through method 'setCounterService' parameter 0: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:648)
      at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:776)
      at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861)
      at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541)
      at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
      at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:369)
      at org.springframework.boot.SpringApplication.run(SpringApplication.java:313)
      at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:111)
      at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:98)
      at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:116)
      ... 22 more
  Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'someMetrics': Unsatisfied dependency expressed through method 'setCounterService' parameter 0: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:648)
      at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
      at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
      at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
      at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
      at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
      at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
      at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:207)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1214)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1054)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1019)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:640)
      ... 40 more
  Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.boot.actuate.metrics.CounterService] found for dependency [org.springframework.boot.actuate.metrics.CounterService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1406)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1057)
      at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1019)
      at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:640)
      ... 54 more
  </code></pre>
  
  <p>Any ideas what have I missed?</p>
  
  <p>P.S.: Also adding the missing SomeMetrics:</p>
  
  <pre><code>package org.project.module.support.metrics;
  
  import org.project.module.support.SomeProperties;
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.beans.factory.annotation.Value;
  import org.springframework.boot.actuate.metrics.CounterService;
  import org.springframework.boot.actuate.metrics.GaugeService;
  import org.springframework.stereotype.Component;
  
  import javax.annotation.PostConstruct;
  
  import static org.mockito.Mockito.mock;
  
  /**
   * Customization for Spring Actuator, defines application-specific counters and metrics.
   *
   * @author istepanov
   */
  @Component
  public class SomeMetrics {
  
      @Value("${const.metrics.some.connections.current:some.connections.created}")
      private String connectorsCurrent;
      @Value("${const.metrics.some.connections.idle:some.connections.idle}")
      private String connectorsIdle;
      @Value("${const.metrics.some.connections.max:some.connections.max}")
      private String connectorsMax;
  
      private CounterService counterService;
      private GaugeService gaugeService;
      private SomeProperties someProperties;
  
      @Autowired
      public void setSomeProperties(SomeProperties someProperties) {
          this.someProperties = someProperties;
      }
  
      @Autowired
      public void setCounterService(CounterService counterService) {
          this.counterService = counterService;
      }
  
      @Autowired
      public void setGaugeService(GaugeService gaugeService) {
          this.gaugeService = gaugeService;
      }
  
      /**
       * Use mocks for {@link CounterService} and {@link GaugeService} if CRMBO is not configured properly.
       */
      @PostConstruct
      public void init() {
          if (someProperties.isMock()) {
              counterService = mock(CounterService.class);
              gaugeService = mock(GaugeService.class);
          }
      }
  
      public void decrementConnectorsCurrent() {
          this.counterService.decrement(connectorsCurrent);
      }
  
      public void incrementConnectorsCurrent() {
          this.counterService.increment(connectorsCurrent);
      }
  
      public void decrementConnectorsIdle() {
          this.counterService.decrement(connectorsIdle);
      }
  
      public void incrementConnectorsIdle() {
          this.counterService.increment(connectorsIdle);
      }
  
      public void decrementConnectorsMax() {
          this.counterService.decrement(connectorsMax);
      }
  
      public void incrementConnectorsMax() {
          this.counterService.increment(connectorsMax);
      }
  }
  </code></pre>