Add ability to run tests with different config profiles

docs/src/main/asciidoc/getting-started-testing.adoc

@@ -303,6 +303,61 @@ public class TestStereotypeTestCase {
 }
 ----
 
+== Testing Different Profiles
+
+So far in all our examples we only start Quarkus once for all tests. Before the first test is run Quarkus will boot,
+then all tests will run, then Quarkus will shutdown at the end. This makes for a very fast testing experience however
+it is a bit limited as you can't test different configurations.
+
+To get around this Quarkus supports the idea of a test profile. If a test has a different profile to the previously
+run test then Quarkus will be shut down and started with the new profile before running the tests. This is obviously
+a bit slower, as it adds a shutdown/startup cycle to the test time, but gives a great deal of flexibility.
+
+NOTE: In order to reduce the amount of times Quarkus needs to restart it is recommended that you place all tests
+that need a specific profile into their own package, and then run tests alphabetically.
+
+=== Writing a Profile
+
+To implement a test profile we need to implement `io.quarkus.test.junit.QuarkusTestProfile`:
+
+[source,java]
+----
+package org.acme.getting.started.testing;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+
+import io.quarkus.test.junit.QuarkusTestProfile;
+
+public class MockGreetingProfile implements QuarkusTestProfile {
+
+    @Override
+    public Map<String, String> getConfigOverrides() { <1>
+        return Collections.singletonMap("quarkus.resteasy.path","/api");
+    }
+
+    @Override
+    public Set<Class<?>> getEnabledAlternatives() { <2>
+        return Collections.singleton(MockGreetingService.class);
+    }
+
+
+    @Override
+    public String getConfigProfile() { <3>
+        return "test";
+    }
+}
+----
+<1> This method allows us to override configuration properties. Here we are changing the JAX-RS root path.
+<2> This method allows us to enable CDI `@Alternative` beans. This makes it easy to mock out certain beans functionality.
+<3> This can be used to change the config profile. As this default is `test` this does nothing, but is included for completeness.
+
+Now we have defined our profile we need to include it on our test class. We do this with `@TestProfile(MockGreetingProfile.class)`.
+
+All the test profile config is stored in a single class, which makes it easy to tell if the previous test ran with the
+same configuration.
+
 
 == Mock Support
 
@@ -311,9 +366,9 @@ mock out a bean for all test classes, or use `QuarkusMock` to mock out beans on
 
 === CDI `@Alternative` mechanism.
 
-To use this simply override the bean you wish to mock with a class in the `src/test/java` directory, and put the `@Alternative` and `@Priority(1)` annotations on the bean. 
+To use this simply override the bean you wish to mock with a class in the `src/test/java` directory, and put the `@Alternative` and `@Priority(1)` annotations on the bean.
 Alternatively, a convenient `io.quarkus.test.Mock` stereotype annotation could be used.
-This built-in stereotype declares `@Alternative`, `@Priority(1)` and `@Dependent`. 
+This built-in stereotype declares `@Alternative`, `@Priority(1)` and `@Dependent`.
 For example if I have the following service:
 
 [source,java]
@@ -596,7 +651,7 @@ public class SpyGreetingServiceTest {
 
 ==== Using `@InjectMock` with `@RestClient`
 
-The `@RegisterRestClient` registers the implementation of the rest-client at runtime, and because the bean needs to be a regular scope, you have to annotate your interface with `@ApplicationScoped`. 
+The `@RegisterRestClient` registers the implementation of the rest-client at runtime, and because the bean needs to be a regular scope, you have to annotate your interface with `@ApplicationScoped`.
 
 [source,java]
 ----
@@ -612,7 +667,7 @@ public interface GreetingService {
 }
 ----
 
-For the test class here is an example: 
+For the test class here is an example:
 
 [source,java]
 ----

integration-tests/main/pom.xml

@@ -199,6 +199,13 @@
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <configuration>
+                    <runOrder>alphabetical</runOrder>
+                </configuration>
+            </plugin>
         </plugins>
     </build>
 

integration-tests/main/src/main/java/io/quarkus/it/rest/GreetingEndpoint.java

@@ -0,0 +1,23 @@
+package io.quarkus.it.rest;
+
+import javax.inject.Inject;
+import javax.ws.rs.GET;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+
+import org.jboss.resteasy.annotations.jaxrs.PathParam;
+
+@Path("/greeting")
+public class GreetingEndpoint {
+
+    @Inject
+    GreetingService greetingService;
+
+    @GET
+    @Produces(MediaType.TEXT_PLAIN)
+    @Path("{name}")
+    public String greet(@PathParam String name) {
+        return greetingService.greet(name);
+    }
+}

integration-tests/main/src/main/java/io/quarkus/it/rest/GreetingService.java

@@ -0,0 +1,10 @@
+package io.quarkus.it.rest;
+
+import javax.enterprise.context.ApplicationScoped;
+
+@ApplicationScoped
+public class GreetingService {
+    public String greet(String greeting) {
+        return "Hello " + greeting;
+    }
+}

integration-tests/main/src/test/java/io/quarkus/it/main/BonjourService.java

@@ -0,0 +1,16 @@
+package io.quarkus.it.main;
+
+import javax.enterprise.context.ApplicationScoped;
+import javax.enterprise.inject.Alternative;
+
+import io.quarkus.it.rest.GreetingService;
+
+@ApplicationScoped
+@Alternative
+public class BonjourService extends GreetingService {
+
+    @Override
+    public String greet(String greeting) {
+        return "Bonjour " + greeting;
+    }
+}

integration-tests/main/src/test/java/io/quarkus/it/main/GreetingNormalTestCase.java

@@ -0,0 +1,21 @@
+package io.quarkus.it.main;
+
+import static org.hamcrest.Matchers.is;
+
+import org.junit.jupiter.api.Test;
+
+import io.quarkus.test.junit.QuarkusTest;
+import io.restassured.RestAssured;
+
+@QuarkusTest
+public class GreetingNormalTestCase {
+
+    @Test
+    public void included() {
+        RestAssured.when()
+                .get("/greeting/Stu")
+                .then()
+                .statusCode(200)
+                .body(is("Hello Stu"));
+    }
+}

integration-tests/main/src/test/java/io/quarkus/it/main/GreetingProfileTestCase.java

@@ -0,0 +1,50 @@
+package io.quarkus.it.main;
+
+import static org.hamcrest.Matchers.is;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import io.quarkus.test.junit.QuarkusTest;
+import io.quarkus.test.junit.QuarkusTestProfile;
+import io.quarkus.test.junit.TestProfile;
+import io.restassured.RestAssured;
+
+/**
+ * Tests that QuarkusTestProfile works as expected
+ */
+@QuarkusTest
+@TestProfile(GreetingProfileTestCase.MyProfile.class)
+public class GreetingProfileTestCase {
+
+    @Test
+    public void included() {
+        RestAssured.when()
+                .get("/greeting/Stu")
+                .then()
+                .statusCode(200)
+                .body(is("Bonjour Stu"));
+    }
+
+    @Test
+    public void testPortTakesEffect() {
+        Assertions.assertEquals(7777, RestAssured.port);
+    }
+
+    public static class MyProfile implements QuarkusTestProfile {
+
+        @Override
+        public Map<String, String> getConfigOverrides() {
+            return Collections.singletonMap("quarkus.http.test-port", "7777");
+        }
+
+        @Override
+        public Set<Class<?>> getEnabledAlternatives() {
+            return Collections.singleton(BonjourService.class);
+        }
+    }
+}

test-framework/junit5/src/main/java/io/quarkus/test/junit/QuarkusTestExtension.java

@@ -15,11 +15,15 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.ServiceLoader;
 import java.util.concurrent.LinkedBlockingDeque;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import java.util.stream.Collectors;
+
+import javax.enterprise.inject.Alternative;
 
 import org.eclipse.microprofile.config.spi.ConfigProviderResolver;
 import org.jboss.jandex.AnnotationInstance;
@@ -54,6 +58,7 @@
 import io.quarkus.deployment.builditem.TestAnnotationBuildItem;
 import io.quarkus.deployment.builditem.TestClassBeanBuildItem;
 import io.quarkus.deployment.builditem.TestClassPredicateBuildItem;
+import io.quarkus.runtime.configuration.ProfileManager;
 import io.quarkus.test.common.PathTestHelper;
 import io.quarkus.test.common.PropertyTestUtil;
 import io.quarkus.test.common.RestAssuredURLManager;
@@ -90,10 +95,12 @@ public class QuarkusTestExtension
     private static List<Object> beforeEachCallbacks = new ArrayList<>();
     private static List<Object> afterEachCallbacks = new ArrayList<>();
     private static Class<?> quarkusTestMethodContextClass;
+    private static Class<? extends QuarkusTestProfile> quarkusTestProfile;
 
     private static DeepClone deepClone;
 
-    private ExtensionState doJavaStart(ExtensionContext context) throws Throwable {
+    private ExtensionState doJavaStart(ExtensionContext context, Class<? extends QuarkusTestProfile> profile) throws Throwable {
+        quarkusTestProfile = profile;
         Closeable testResourceManager = null;
         try {
             final LinkedBlockingDeque<Runnable> shutdownTasks = new LinkedBlockingDeque<>();
@@ -114,10 +121,38 @@ private ExtensionState doJavaStart(ExtensionContext context) throws Throwable {
                 }
             }
             originalCl = Thread.currentThread().getContextClassLoader();
+            Map<String, String> sysPropRestore = new HashMap<>();
+            sysPropRestore.put(ProfileManager.QUARKUS_TEST_PROFILE_PROP,
+                    System.getProperty(ProfileManager.QUARKUS_TEST_PROFILE_PROP));
 
             final QuarkusBootstrap.Builder runnerBuilder = QuarkusBootstrap.builder()
                     .setIsolateDeployment(true)
                     .setMode(QuarkusBootstrap.Mode.TEST);
+            if (profile != null) {
+                QuarkusTestProfile profileInstance = profile.newInstance();
+                Map<String, String> additional = new HashMap<>(profileInstance.getConfigOverrides());
+                if (!profileInstance.getEnabledAlternatives().isEmpty()) {
+                    additional.put("quarkus.arc.selected-alternatives", profileInstance.getEnabledAlternatives().stream()
+                            .peek((c) -> {
+                                if (!c.isAnnotationPresent(Alternative.class)) {
+                                    throw new RuntimeException(
+                                            "Enabled alternative " + c + " is not annotated with @Alternative");
+                                }
+                            })
+                            .map(Class::getName).collect(Collectors.joining(",")));
+                }
+                if (profileInstance.getConfigProfile() != null) {
+                    System.setProperty(ProfileManager.QUARKUS_TEST_PROFILE_PROP, profileInstance.getConfigProfile());
+                }
+                //we just use system properties for now
+                //its a lot simpler
+                for (Map.Entry<String, String> i : additional.entrySet()) {
+                    sysPropRestore.put(i.getKey(), System.getProperty(i.getKey()));
+                }
+                for (Map.Entry<String, String> i : additional.entrySet()) {
+                    System.setProperty(i.getKey(), i.getValue());
+                }
+            }
 
             runnerBuilder.setProjectRoot(Paths.get("").normalize().toAbsolutePath());
 
@@ -176,6 +211,14 @@ public void close() throws IOException {
                                 shutdownTasks.pop().run();
                             }
                         } finally {
+                            for (Map.Entry<String, String> entry : sysPropRestore.entrySet()) {
+                                String val = entry.getValue();
+                                if (val == null) {
+                                    System.clearProperty(entry.getKey());
+                                } else {
+                                    System.setProperty(entry.getKey(), val);
+                                }
+                            }
                             tm.close();
                         }
                     }
@@ -305,10 +348,25 @@ private ExtensionState ensureStarted(ExtensionContext extensionContext) {
         ExtensionContext root = extensionContext.getRoot();
         ExtensionContext.Store store = root.getStore(ExtensionContext.Namespace.GLOBAL);
         ExtensionState state = store.get(ExtensionState.class.getName(), ExtensionState.class);
-        if (state == null && !failedBoot) {
+        TestProfile annotation = extensionContext.getRequiredTestClass().getAnnotation(TestProfile.class);
+        Class<? extends QuarkusTestProfile> selectedProfile = null;
+        if (annotation != null) {
+            selectedProfile = annotation.value();
+        }
+        boolean wrongProfile = !Objects.equals(selectedProfile, quarkusTestProfile);
+        if ((state == null && !failedBoot) || wrongProfile) {
+            if (wrongProfile) {
+                if (state != null) {
+                    try {
+                        state.close();
+                    } catch (Throwable throwable) {
+                        throwable.printStackTrace();
+                    }
+                }
+            }
             PropertyTestUtil.setLogFileProperty();
             try {
-                state = doJavaStart(extensionContext);
+                state = doJavaStart(extensionContext, selectedProfile);
                 store.put(ExtensionState.class.getName(), state);
 
             } catch (Throwable e) {

test-framework/junit5/src/main/java/io/quarkus/test/junit/QuarkusTestProfile.java

@@ -0,0 +1,42 @@
+package io.quarkus.test.junit;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * Defines a 'test profile'. Tests run under a test profile
+ * will have different configuration options to other tests.
+ *
+ */
+public interface QuarkusTestProfile {
+
+    /**
+     * Returns additional config to be applied to the test. This
+     * will override any existing config (including in application.properties),
+     * however existing config will be merged with this (i.e. application.properties
+     * config will still take effect, unless a specific config key has been overridden).
+     */
+    default Map<String, String> getConfigOverrides() {
+        return Collections.emptyMap();
+    }
+
+    /**
+     * Returns enabled alternatives.
+     *
+     * This has the same effect as setting the 'quarkus.arc.selected-alternatives' config key,
+     * however it may be more convenient.
+     */
+    default Set<Class<?>> getEnabledAlternatives() {
+        return Collections.emptySet();
+    }
+
+    /**
+     * Allows the default config profile to be overridden. This basically just sets the quarkus.test.profile system
+     * property before the test is run.
+     *
+     */
+    default String getConfigProfile() {
+        return null;
+    }
+}