4.x: Ability to Inject MockBeans in Helidon #7694

Signed-off-by: Jorge Bescos Gascon <[email protected]>

Author: jbescos

microprofile/testing/junit5/pom.xml

@@ -54,6 +54,11 @@
             <artifactId>junit-jupiter-api</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>io.helidon.jersey</groupId>
             <artifactId>helidon-jersey-client</artifactId>

microprofile/testing/junit5/src/main/java/io/helidon/microprofile/testing/junit5/HelidonJunitExtension.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -28,6 +28,7 @@
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -48,7 +49,10 @@
 import jakarta.enterprise.inject.spi.CDI;
 import jakarta.enterprise.inject.spi.Extension;
 import jakarta.enterprise.inject.spi.InjectionPoint;
+import jakarta.enterprise.inject.spi.ProcessAnnotatedType;
 import jakarta.enterprise.inject.spi.ProcessInjectionPoint;
+import jakarta.enterprise.inject.spi.WithAnnotations;
+import jakarta.enterprise.inject.spi.configurator.AnnotatedFieldConfigurator;
 import jakarta.enterprise.inject.spi.configurator.AnnotatedTypeConfigurator;
 import jakarta.enterprise.util.AnnotationLiteral;
 import jakarta.inject.Inject;
@@ -73,6 +77,7 @@
 import org.junit.jupiter.api.extension.ParameterResolutionException;
 import org.junit.jupiter.api.extension.ParameterResolver;
 import org.junit.jupiter.api.extension.ReflectiveInvocationContext;
+import org.mockito.Mockito;
 
 
 /**
@@ -288,6 +293,11 @@ private void validatePerTest() {
                                                    + " injection into fields or constructor is not supported, as each"
                                                    + " test method uses a different CDI container. Field " + field
                                                    + " is annotated with @Inject");
+            } else if (field.getAnnotation(MockBean.class) != null) {
+                throw new RuntimeException("When a class is annotated with @HelidonTest(resetPerTest=true),"
+                        + " injection into fields or constructor is not supported, as each"
+                        + " test method uses a different CDI container. Field " + field
+                        + " is annotated with @MockBean");
             }
         }
 
@@ -298,6 +308,11 @@ private void validatePerTest() {
                                                    + " injection into fields or constructor is not supported, as each"
                                                    + " test method uses a different CDI container. Field " + field
                                                    + " is annotated with @Inject");
+            } else if (field.getAnnotation(MockBean.class) != null) {
+                throw new RuntimeException("When a class is annotated with @HelidonTest(resetPerTest=true),"
+                        + " injection into fields or constructor is not supported, as each"
+                        + " test method uses a different CDI container. Field " + field
+                        + " is annotated with @MockBean");
             }
         }
     }
@@ -504,6 +519,7 @@ private static class AddBeansExtension implements Extension {
         private final List<AddBean> addBeans;
 
         private final HashMap<String, Annotation> socketAnnotations = new HashMap<>();
+        private final Set<Class<?>> mocks = new HashSet<>();
 
         private AddBeansExtension(Class<?> testClass, List<AddBean> addBeans) {
             this.testClass = testClass;
@@ -521,7 +537,18 @@ void processSocketInjectionPoints(@Observes ProcessInjectionPoint<?, WebTarget>
                         break;
                     }
                 }
+        }
 
+        void processMockBean(@Observes @WithAnnotations(MockBean.class) ProcessAnnotatedType<?> obj) throws Exception {
+            var configurator = obj.configureAnnotatedType();
+            for (AnnotatedFieldConfigurator<?> field : configurator.fields()) {
+                MockBean mockBean = field.getAnnotated().getAnnotation(MockBean.class);
+                if (mockBean != null) {
+                    Field f = field.getAnnotated().getJavaMember();
+                    Class<?> fieldType = f.getType();
+                    mocks.add(fieldType);
+                }
+            }
         }
 
         void registerOtherBeans(@Observes AfterBeanDiscovery event) {
@@ -543,6 +570,13 @@ void registerOtherBeans(@Observes AfterBeanDiscovery event) {
                     .scope(ApplicationScoped.class)
                     .createWith(context -> getWebTarget(client, "@default"));
 
+            // Register all mocks
+            mocks.forEach(type -> {
+                event.addBean()
+                    .addType(type)
+                    .scope(ApplicationScoped.class)
+                    .createWith(inst -> Mockito.mock(type));
+            });
         }
 
         @SuppressWarnings("unchecked")

microprofile/testing/junit5/src/main/java/io/helidon/microprofile/testing/junit5/MockBean.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2024 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.helidon.microprofile.testing.junit5;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * A field annotated with @MockBean will be mocked by Mockito
+ * and injected in every place it is referenced.
+ */
+@Target({ElementType.FIELD})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface MockBean {
+}

microprofile/testing/junit5/src/main/java/module-info.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2023 Oracle and/or its affiliates.
+ * Copyright (c) 2020, 2024 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,6 +24,7 @@
     requires io.helidon.microprofile.cdi;
     requires jakarta.inject;
     requires org.junit.jupiter.api;
+    requires org.mockito;
 
     requires transitive jakarta.cdi;
     requires transitive jakarta.ws.rs;

microprofile/tests/testing/junit5/pom.xml

@@ -55,5 +55,10 @@
             <artifactId>hamcrest-core</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 </project>

microprofile/tests/testing/junit5/src/test/java/io/helidon/microprofile/tests/testing/junit5/TestMockBean.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2024 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.helidon.microprofile.tests.testing.junit5;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import jakarta.inject.Inject;
+import jakarta.ws.rs.GET;
+import jakarta.ws.rs.Path;
+import jakarta.ws.rs.client.WebTarget;
+
+import io.helidon.microprofile.testing.junit5.AddBean;
+import io.helidon.microprofile.testing.junit5.HelidonTest;
+import io.helidon.microprofile.testing.junit5.MockBean;
+
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+@HelidonTest
+@AddBean(TestMockBean.Resource.class)
+//@AddBean(TestMockBean.Service.class)
+public class TestMockBean {
+
+    @Inject
+    @MockBean
+    private Service service;
+    @Inject
+    private WebTarget target;
+
+    @Test
+    public void injectionTest() {
+        Mockito.when(service.test()).thenReturn("Mocked");
+        String response = target.path("/test").request().get(String.class);
+        assertThat(response, is("Mocked"));
+    }
+
+    @Path("/test")
+    public static class Resource {
+
+        @Inject
+        private Service service;
+
+        @GET
+        public String test() {
+            return service.test();
+        }
+    }
+
+    public static class Service {
+
+        public String test() {
+            return "Not Mocked";
+        }
+
+    }
+}