Add Spring Boot integration.

docs/README.md

@@ -3,4 +3,5 @@
 * [Testing frameworks support](test_frameworks_support.md)
 * [Customization](customization.md)
 * [How it works](how_it_works.md)
+* [Spring support](spring_support.md)
 * [Writing custom integrations](custom_integrations.md)

docs/spring_support.md

@@ -0,0 +1,26 @@
+# Spring support
+
+BlockHound Spring module will automatically install the agent at a very early stage of Spring Boot application's startup.
+
+## Getting it
+Download it from repo.spring.io or Maven Central repositories (stable releases only):
+
+```groovy
+repositories {
+  maven { url 'https://repo.spring.io/milestone' }
+  // maven { url 'https://repo.spring.io/snapshot' }
+}
+
+dependencies {
+  testCompile 'io.projectreactor.tools:blockhound-spring:$LATEST_RELEASE'
+  // testCompile 'io.projectreactor.tools:blockhound-spring:$LATEST_SNAPSHOT'
+}
+```
+Where:  
+`$LATEST_RELEASE` is: ![](https://img.shields.io/maven-metadata/v/https/repo.spring.io/milestone/io/projectreactor/tools/blockhound-spring/maven-metadata.xml.svg?label=)  
+`$LATEST_SNAPSHOT` is: ![](https://img.shields.io/maven-metadata/v/https/repo.spring.io/snapshot/io/projectreactor/tools/blockhound-spring/maven-metadata.xml.svg?label=)
+
+## Custom config
+The listener will call `install()` without the arguments (see [customization](./customization.md) for details).
+
+If you want to apply your custom integration, register it as any other integration as documented [here](./custom_integrations.md).

settings.gradle

@@ -3,5 +3,6 @@ rootProject.name = 'reactor-block-hound'
 
 include 'agent'
 include 'native-agent'
+include 'spring'
 include 'example'
 include 'junit-platform'

spring/build.gradle

@@ -0,0 +1,42 @@
+plugins {
+    id "java"
+    id "maven-publish"
+}
+
+sourceCompatibility = targetCompatibility = 8
+
+repositories {
+    jcenter()
+}
+
+dependencies {
+    compile project(path: ":agent", configuration: 'shadow')
+
+    compileOnly 'org.springframework.boot:spring-boot:2.1.3.RELEASE'
+
+    testCompile 'junit:junit:4.12'
+    testCompile 'org.assertj:assertj-core:3.11.1'
+    testCompile 'org.springframework.boot:spring-boot:2.1.3.RELEASE'
+    testCompile 'io.projectreactor:reactor-core:3.2.2.RELEASE'
+}
+
+test {
+    forkEvery = 1
+    maxParallelForks = 1
+}
+
+task sourcesJar(type: Jar) {
+    classifier 'sources'
+    from sourceSets.main.allJava
+}
+
+publishing {
+    publications {
+        mavenJava(MavenPublication) { publication ->
+            from components.java
+            artifact sourcesJar
+
+            artifactId 'blockhound-spring'
+        }
+    }
+}

spring/src/main/java/reactor/blockhound/spring/BlockHoundRunListener.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2019-Present Pivotal Software Inc, All Rights Reserved.
+ *
+ * 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
+ *
+ *       https://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 reactor.blockhound.spring;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.SpringApplicationRunListener;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.Ordered;
+import org.springframework.core.env.ConfigurableEnvironment;
+import reactor.BlockHound;
+import reactor.blockhound.integration.BlockHoundIntegration;
+
+/**
+ * This {@link SpringApplicationRunListener} installs the agent when an app is starting
+ * by calling {@link BlockHound#install(BlockHoundIntegration...)}.
+ */
+public class BlockHoundRunListener implements SpringApplicationRunListener, Ordered {
+
+    public BlockHoundRunListener(SpringApplication application, String[] args) {
+
+    }
+
+    @Override
+    public int getOrder() {
+        return Ordered.HIGHEST_PRECEDENCE;
+    }
+
+    @Override
+    public void starting() {
+        BlockHound.install();
+    }
+
+    @Override
+    public void environmentPrepared(ConfigurableEnvironment environment) {
+
+    }
+
+    @Override
+    public void contextPrepared(ConfigurableApplicationContext context) {
+
+    }
+
+    @Override
+    public void contextLoaded(ConfigurableApplicationContext context) {
+
+    }
+
+    @Override
+    public void started(ConfigurableApplicationContext context) {
+
+    }
+
+    @Override
+    public void running(ConfigurableApplicationContext context) {
+
+    }
+
+    @Override
+    public void failed(ConfigurableApplicationContext context, Throwable exception) {
+
+    }
+}

spring/src/main/resources/META-INF/spring.factories

@@ -0,0 +1,3 @@
+# Run Listeners
+org.springframework.boot.SpringApplicationRunListener=\
+reactor.blockhound.spring.BlockHoundRunListener

spring/src/test/java/reactor/blockhound/spring/BlockHoundRunListenerTest.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2019-Present Pivotal Software Inc, All Rights Reserved.
+ *
+ * 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
+ *
+ *       https://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 reactor.blockhound.spring;
+
+import org.assertj.core.api.AbstractThrowableAssert;
+import org.assertj.core.api.Assertions;
+import org.junit.Test;
+import org.springframework.boot.SpringApplication;
+import org.springframework.context.annotation.Configuration;
+import reactor.core.publisher.Mono;
+import reactor.core.scheduler.Schedulers;
+
+import java.io.Closeable;
+
+public class BlockHoundRunListenerTest {
+
+    @Test
+    public void shouldInstallOnRun() throws Exception {
+        assertThatBlockingCall().doesNotThrowAnyException();
+
+        try (Closeable __ = new SpringApplication(DummyAppConfiguration.class).run()) {
+            assertThatBlockingCall().hasMessageContaining("Blocking call!");
+        }
+    }
+
+    private AbstractThrowableAssert<?, ? extends Throwable> assertThatBlockingCall() {
+        return Assertions.assertThatCode(() -> {
+            Mono
+                    .fromCallable(() -> {
+                        Thread.sleep(1);
+                        return "";
+                    })
+                    .subscribeOn(Schedulers.parallel())
+                    .block();
+        });
+    }
+
+    @Configuration
+    static class DummyAppConfiguration {
+    }
+
+}