Merge pull request #66 from brharrington/0.14.x-guice-module

0.14.x guice module

build.gradle

@@ -130,9 +130,11 @@ project(':spectator-nflx-plugin') {
     compile project(':spectator-ext-gc')
     compile project(':spectator-ext-jvm')
     compile project(':spectator-reg-servo')
+    compile 'com.google.inject:guice:3.0'
     compile 'com.netflix.archaius:archaius-core:0.6.3'
     compile 'com.netflix.governator:governator:1.2.20'
     compile 'com.netflix.ribbon:ribbon-transport:2.0-RC9'
+    testCompile 'com.netflix.governator:governator:1.2.20'
   }
 }
 

spectator-ext-gc/src/main/java/com/netflix/spectator/gc/GcLogger.java

@@ -113,7 +113,13 @@ public GcLogger() {
    *     log buffer is updated.
    */
   public synchronized void start(GcEventListener listener) {
-    Preconditions.checkState(notifListener == null, "logger already started");
+    // TODO: this class has a bad mix of static fields used from an instance of the class. For now
+    // this has been changed not to throw to make the dependency injection use-cases work. A
+    // more general refactor of the GcLogger class is needed.
+    if (notifListener != null) {
+      LOGGER.warn("logger already started");
+      return;
+    }
     eventListener = listener;
     notifListener = new GcNotificationListener();
     for (GarbageCollectorMXBean mbean : ManagementFactory.getGarbageCollectorMXBeans()) {

spectator-nflx-plugin/src/main/java/com/netflix/spectator/nflx/SpectatorModule.java

@@ -0,0 +1,62 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * 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 com.netflix.spectator.nflx;
+
+import com.google.inject.AbstractModule;
+import com.netflix.spectator.api.ExtendedRegistry;
+import com.netflix.spectator.api.Registry;
+import com.netflix.spectator.api.Spectator;
+
+/**
+ * Guice module to configure the appropriate bindings for running an application. Note that this
+ * will configure it to use the global registry bindings for reporting. This also means that test
+ * cases will not be completely isolated. For unit tests see
+ * {@link com.netflix.spectator.nflx.TestModule}. Typical usage:
+ *
+ * <p><b>User code</b></p>
+ * <pre>
+ * public class Foo {
+ *   private final Counter counter;
+ *
+ *  {@literal @}Inject
+ *   public Foo(ExtendedRegistry registry) {
+ *     counter = registry.counter("foo.doSomething");
+ *   }
+ *
+ *   public void doSomething() {
+ *     counter.increment();
+ *   }
+ * }
+ * </pre>
+ *
+ * <p><b>Governator</b></p>
+ * <p>One of the classes requires an {@link javax.annotation.PostConstruct} block to initialize
+ * so governator should be used to manage the lifecycle as guice doesn't support it directly.</p>
+ * <pre>
+ * Injector injector = LifecycleInjector.builder()
+ *   .withModules(new SpectatorModule())
+ *   .build()
+ *   .createInjector();
+ * injector.getInstance(LifecycleManager.class).start();
+ * </pre>
+ */
+public class SpectatorModule extends AbstractModule {
+  @Override protected void configure() {
+    bind(Plugin.class).asEagerSingleton();
+    bind(ExtendedRegistry.class).toInstance(Spectator.registry());
+    bind(Registry.class).toInstance(Spectator.registry());
+  }
+}

spectator-nflx-plugin/src/main/java/com/netflix/spectator/nflx/TestModule.java

@@ -0,0 +1,37 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * 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 com.netflix.spectator.nflx;
+
+import com.google.inject.AbstractModule;
+import com.netflix.spectator.api.DefaultRegistry;
+import com.netflix.spectator.api.ExtendedRegistry;
+import com.netflix.spectator.api.Registry;
+
+/**
+ * Guice module to configure the appropriate bindings for unit tests. Note that this module will
+ * create a registry that only keeps data in-memory and is scoped to the injector. If used when
+ * running the application you will not be able to see the data and it will not get reported off
+ * the instance. In particular, it is completely independent of the main registry accessed by
+ * calling {@link com.netflix.spectator.api.Spectator#registry()}. Use the
+ * {@link com.netflix.spectator.nflx.SpectatorModule} when running code outside of unit tests.
+ */
+public class TestModule extends AbstractModule {
+  @Override protected void configure() {
+    final ExtendedRegistry registry = new ExtendedRegistry(new DefaultRegistry());
+    bind(ExtendedRegistry.class).toInstance(registry);
+    bind(Registry.class).toInstance(registry);
+  }
+}

spectator-nflx-plugin/src/test/java/com/netflix/spectator/nflx/SpectatorModuleTest.java

@@ -0,0 +1,81 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * 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 com.netflix.spectator.nflx;
+
+import com.google.inject.Guice;
+import com.google.inject.Inject;
+import com.google.inject.Injector;
+import com.netflix.governator.guice.LifecycleInjector;
+import com.netflix.governator.lifecycle.LifecycleManager;
+import com.netflix.spectator.api.Counter;
+import com.netflix.spectator.api.ExtendedRegistry;
+import com.netflix.spectator.api.Spectator;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class SpectatorModuleTest {
+
+  public static class Foo {
+    private final Counter counter;
+
+    @Inject
+    public Foo(ExtendedRegistry registry) {
+      counter = registry.counter("foo.doSomething");
+    }
+
+    public void doSomething() {
+      counter.increment();
+    }
+  }
+
+  private Injector injector;
+
+  @Before
+  public void setup() throws Exception {
+    injector = LifecycleInjector.builder()
+        .withModules(new SpectatorModule())
+        .build()
+        .createInjector();
+    injector.getInstance(LifecycleManager.class).start();
+  }
+
+  @After
+  public void cleanup() {
+    injector.getInstance(LifecycleManager.class).close();
+  }
+
+  @Test
+  public void checkCount() {
+    ExtendedRegistry r = injector.getInstance(ExtendedRegistry.class);
+    Counter c = r.counter("foo.doSomething");
+    long before = c.count();
+
+    Foo f = injector.getInstance(Foo.class);
+    f.doSomething();
+    Assert.assertEquals(before + 1, c.count());
+  }
+
+  @Test
+  public void isGlobal() {
+    ExtendedRegistry r = injector.getInstance(ExtendedRegistry.class);
+    Assert.assertSame(Spectator.registry(), r);
+  }
+}

spectator-nflx-plugin/src/test/java/com/netflix/spectator/nflx/TestModuleTest.java

@@ -0,0 +1,69 @@
+/**
+ * Copyright 2014 Netflix, Inc.
+ *
+ * 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 com.netflix.spectator.nflx;
+
+import com.google.inject.Guice;
+import com.google.inject.Inject;
+import com.google.inject.Injector;
+import com.netflix.spectator.api.Counter;
+import com.netflix.spectator.api.ExtendedRegistry;
+import com.netflix.spectator.api.Spectator;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+@RunWith(JUnit4.class)
+public class TestModuleTest {
+
+  public static class Foo {
+    private final Counter counter;
+
+    @Inject
+    public Foo(ExtendedRegistry registry) {
+      counter = registry.counter("foo.doSomething");
+    }
+
+    public void doSomething() {
+      counter.increment();
+    }
+  }
+
+  private Injector injector;
+
+  @Before
+  public void setup() {
+    injector = Guice.createInjector(new TestModule());
+  }
+
+  @Test
+  public void checkCount() {
+    ExtendedRegistry r = injector.getInstance(ExtendedRegistry.class);
+    Counter c = r.counter("foo.doSomething");
+    Assert.assertEquals(0, c.count());
+
+    Foo f = injector.getInstance(Foo.class);
+    f.doSomething();
+    Assert.assertEquals(1, c.count());
+  }
+
+  @Test
+  public void notGlobal() {
+    ExtendedRegistry r = injector.getInstance(ExtendedRegistry.class);
+    Assert.assertNotSame(Spectator.registry(), r);
+  }
+}