druid.coordinator.asOverlord.enabled flag at coordinator to make it a…

…n overlord too (apache#3711)

docs/content/configuration/coordinator.md

@@ -34,6 +34,8 @@ The coordinator node uses several of the global configs in [Configuration](../co
 |`druid.coordinator.kill.maxSegments`|Kill at most n segments per kill task submission, must be greater than 0. Only applies and MUST be specified if kill is turned on. Note that default value is invalid.|0|
 |`druid.coordinator.balancer.strategy`|Specify the type of balancing strategy that the coordinator should use to distribute segments among the historicals. Use `diskNormalized` to distribute segments among nodes so that the disks fill up uniformly and use `random` to randomly pick nodes to distribute segments.|`cost`|
 |`druid.coordinator.loadqueuepeon.repeatDelay`|The start and repeat delay for the loadqueuepeon , which manages the load and drop of segments.|PT0.050S (50 ms)|
+|`druid.coordinator.asOverlord.enabled`|Boolean value for whether this coordinator node should act like an overlord as well. This configuration allows users to simplify a druid cluster by not having to deploy any standalone overlord nodes. If set to true, then be sure to set `druid.coordinator.asOverlord.overlordService` also. See next.|false|
+|`druid.coordinator.asOverlord.overlordService`| Required, if `druid.coordinator.asOverlord.enabled` is `true`. This must be same value as `druid.service` on standalone Overlord nodes and `druid.selectors.indexing.serviceName` on Middle Managers.|NULL|
 
 ### Metadata Retrieval
 

indexing-service/src/main/java/io/druid/indexing/overlord/TaskMaster.java

@@ -37,6 +37,7 @@
 import io.druid.java.util.common.lifecycle.LifecycleStart;
 import io.druid.java.util.common.lifecycle.LifecycleStop;
 import io.druid.server.DruidNode;
+import io.druid.server.coordinator.CoordinatorOverlordServiceConfig;
 import io.druid.server.initialization.IndexerZkConfig;
 import org.apache.curator.framework.CuratorFramework;
 import org.apache.curator.framework.recipes.leader.LeaderSelector;
@@ -73,18 +74,23 @@ public TaskMaster(
       final TaskLockbox taskLockbox,
       final TaskStorage taskStorage,
       final TaskActionClientFactory taskActionClientFactory,
-      @Self final DruidNode node,
+      @Self final DruidNode selfNode,
       final IndexerZkConfig zkPaths,
       final TaskRunnerFactory runnerFactory,
       final CuratorFramework curator,
       final ServiceAnnouncer serviceAnnouncer,
+      final CoordinatorOverlordServiceConfig coordinatorOverlordServiceConfig,
       final ServiceEmitter emitter,
       final SupervisorManager supervisorManager,
       final OverlordHelperManager overlordHelperManager
   )
   {
     this.supervisorManager = supervisorManager;
     this.taskActionClientFactory = taskActionClientFactory;
+
+    final DruidNode node = coordinatorOverlordServiceConfig.getOverlordService() == null ? selfNode :
+                           selfNode.withService(coordinatorOverlordServiceConfig.getOverlordService());
+
     this.leaderSelector = new LeaderSelector(
         curator,
         zkPaths.getLeaderLatchPath(),

indexing-service/src/main/java/io/druid/indexing/overlord/http/OverlordRedirectInfo.java

@@ -40,7 +40,7 @@ public OverlordRedirectInfo(TaskMaster taskMaster)
   }
 
   @Override
-  public boolean doLocal()
+  public boolean doLocal(String requestURI)
   {
     return taskMaster.isLeading();
   }

indexing-service/src/test/java/io/druid/indexing/overlord/http/OverlordRedirectInfoTest.java

@@ -44,7 +44,7 @@ public void testDoLocal()
   {
     EasyMock.expect(taskMaster.isLeading()).andReturn(true).anyTimes();
     EasyMock.replay(taskMaster);
-    Assert.assertTrue(redirectInfo.doLocal());
+    Assert.assertTrue(redirectInfo.doLocal(null));
     EasyMock.verify(taskMaster);
   }
 

indexing-service/src/test/java/io/druid/indexing/overlord/http/OverlordTest.java

@@ -53,6 +53,7 @@
 import io.druid.java.util.common.Pair;
 import io.druid.java.util.common.guava.CloseQuietly;
 import io.druid.server.DruidNode;
+import io.druid.server.coordinator.CoordinatorOverlordServiceConfig;
 import io.druid.server.initialization.IndexerZkConfig;
 import io.druid.server.initialization.ZkPathsConfig;
 import io.druid.server.metrics.NoopServiceEmitter;
@@ -183,6 +184,7 @@ public void announce(DruidNode node)
             announcementLatch.countDown();
           }
         },
+        new CoordinatorOverlordServiceConfig(null, null),
         serviceEmitter,
         supervisorManager,
         EasyMock.createNiceMock(OverlordHelperManager.class)

server/src/main/java/io/druid/server/DruidNode.java

@@ -129,6 +129,11 @@ public int getPort()
     return port;
   }
 
+  public DruidNode withService(String service)
+  {
+    return new DruidNode(service, host, port);
+  }
+
   /**
    * Returns host and port together as something that can be used as part of a URI.
    */

server/src/main/java/io/druid/server/coordinator/CoordinatorOverlordServiceConfig.java

@@ -0,0 +1,56 @@
+/*
+ * Licensed to Metamarkets Group Inc. (Metamarkets) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. Metamarkets licenses this file
+ * to you 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.druid.server.coordinator;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.base.Preconditions;
+
+/**
+ */
+public class CoordinatorOverlordServiceConfig
+{
+  @JsonProperty
+  private final boolean enabled;
+
+  @JsonProperty
+  private final String overlordService;
+
+  public CoordinatorOverlordServiceConfig(
+      @JsonProperty("enabled") Boolean enabled,
+      @JsonProperty("overlordService") String overlordService
+  )
+  {
+    this.enabled = enabled == null ? false : enabled.booleanValue();
+    this.overlordService = overlordService;
+
+    Preconditions.checkArgument((this.enabled && this.overlordService != null) || !this.enabled,
+                                "coordinator is enabled to be overlord but overlordService is not specified");
+  }
+
+  public boolean isEnabled()
+  {
+    return enabled;
+  }
+
+  public String getOverlordService()
+  {
+    return overlordService;
+  }
+}

server/src/main/java/io/druid/server/http/CoordinatorRedirectInfo.java

@@ -37,7 +37,7 @@ public CoordinatorRedirectInfo(DruidCoordinator coordinator) {
   }
 
   @Override
-  public boolean doLocal()
+  public boolean doLocal(String requestURI)
   {
     return coordinator.isLeader();
   }

server/src/main/java/io/druid/server/http/RedirectFilter.java

@@ -68,7 +68,7 @@ public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
       throw new ServletException("non-HTTP request or response");
     }
 
-    if (redirectInfo.doLocal()) {
+    if (redirectInfo.doLocal(request.getRequestURI())) {
       chain.doFilter(request, response);
     } else {
       URL url = redirectInfo.getRedirectURL(request.getQueryString(), request.getRequestURI());

server/src/main/java/io/druid/server/http/RedirectInfo.java

@@ -25,7 +25,7 @@
  */
 public interface RedirectInfo
 {
-  public boolean doLocal();
+  public boolean doLocal(String requestURI);
 
   public URL getRedirectURL(String queryString, String requestURI);
 }

server/src/test/java/io/druid/server/http/CoordinatorRedirectInfoTest.java

@@ -44,7 +44,7 @@ public void testDoLocal()
   {
     EasyMock.expect(druidCoordinator.isLeader()).andReturn(true).anyTimes();
     EasyMock.replay(druidCoordinator);
-    Assert.assertTrue(coordinatorRedirectInfo.doLocal());
+    Assert.assertTrue(coordinatorRedirectInfo.doLocal(null));
     EasyMock.verify(druidCoordinator);
   }
 

services/src/main/java/io/druid/cli/CliCoordinator.java

@@ -21,7 +21,6 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.base.Predicates;
-import com.google.common.collect.ImmutableList;
 import com.google.inject.Binder;
 import com.google.inject.Inject;
 import com.google.inject.Module;
@@ -79,6 +78,7 @@
 import org.apache.curator.framework.CuratorFramework;
 import org.eclipse.jetty.server.Server;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
 import java.util.concurrent.Executors;
@@ -94,6 +94,7 @@ public class CliCoordinator extends ServerRunnable
   private static final Logger log = new Logger(CliCoordinator.class);
 
   private Properties properties;
+  private boolean beOverlord;
 
   public CliCoordinator()
   {
@@ -104,12 +105,19 @@ public CliCoordinator()
   public void configure(Properties properties)
   {
     this.properties = properties;
+    beOverlord = isOverlord(properties);
+
+    if (beOverlord) {
+      log.info("Coordinator is configured to act as Overlord as well.");
+    }
   }
 
   @Override
   protected List<? extends Module> getModules()
   {
-    return ImmutableList.<Module>of(
+    List<Module> modules = new ArrayList<>();
+
+    modules.add(
         new Module()
         {
           @Override
@@ -131,7 +139,11 @@ public void configure(Binder binder)
             JsonConfigProvider.bind(binder, "druid.coordinator.balancer", BalancerStrategyFactory.class);
 
             binder.bind(RedirectFilter.class).in(LazySingleton.class);
-            binder.bind(RedirectInfo.class).to(CoordinatorRedirectInfo.class).in(LazySingleton.class);
+            if (beOverlord) {
+              binder.bind(RedirectInfo.class).to(CoordinatorOverlordRedirectInfo.class).in(LazySingleton.class);
+            } else {
+              binder.bind(RedirectInfo.class).to(CoordinatorRedirectInfo.class).in(LazySingleton.class);
+            }
 
             binder.bind(MetadataSegmentManager.class)
                   .toProvider(MetadataSegmentManagerProvider.class)
@@ -192,7 +204,6 @@ public void configure(Binder binder)
                 Predicates.equalTo("true"),
                 DruidCoordinatorSegmentKiller.class
             );
-
           }
 
           @Provides
@@ -211,5 +222,16 @@ public LoadQueueTaskMaster getLoadQueueTaskMaster(
           }
         }
     );
+
+    if (beOverlord) {
+      modules.addAll(new CliOverlord().getModules(false));
+    }
+
+    return modules;
+  }
+
+  public static boolean isOverlord(Properties properties)
+  {
+    return Boolean.valueOf(properties.getProperty("druid.coordinator.asOverlord.enabled")).booleanValue();
   }
 }

services/src/main/java/io/druid/cli/CliOverlord.java

@@ -79,6 +79,7 @@
 import io.druid.java.util.common.logger.Logger;
 import io.druid.segment.realtime.firehose.ChatHandlerProvider;
 import io.druid.server.audit.AuditManagerProvider;
+import io.druid.server.coordinator.CoordinatorOverlordServiceConfig;
 import io.druid.server.http.RedirectFilter;
 import io.druid.server.http.RedirectInfo;
 import io.druid.server.initialization.jetty.JettyServerInitUtils;
@@ -113,18 +114,26 @@ public CliOverlord()
 
   @Override
   protected List<? extends Module> getModules()
+  {
+    return getModules(true);
+  }
+
+  protected List<? extends Module> getModules(final boolean standalone)
   {
     return ImmutableList.<Module>of(
         new Module()
         {
           @Override
           public void configure(Binder binder)
           {
-            binder.bindConstant()
-                  .annotatedWith(Names.named("serviceName"))
-                  .to(IndexingServiceSelectorConfig.DEFAULT_SERVICE_NAME);
-            binder.bindConstant().annotatedWith(Names.named("servicePort")).to(8090);
-
+            if (standalone) {
+              binder.bindConstant()
+                    .annotatedWith(Names.named("serviceName"))
+                    .to(IndexingServiceSelectorConfig.DEFAULT_SERVICE_NAME);
+              binder.bindConstant().annotatedWith(Names.named("servicePort")).to(8090);
+            }
+
+            JsonConfigProvider.bind(binder, "druid.coordinator.asOverlord", CoordinatorOverlordServiceConfig.class);
             JsonConfigProvider.bind(binder, "druid.indexer.queue", TaskQueueConfig.class);
             JsonConfigProvider.bind(binder, "druid.indexer.task", TaskConfig.class);
 
@@ -160,14 +169,18 @@ public void configure(Binder binder)
                   .toProvider(AuditManagerProvider.class)
                   .in(ManageLifecycle.class);
 
-            binder.bind(RedirectFilter.class).in(LazySingleton.class);
-            binder.bind(RedirectInfo.class).to(OverlordRedirectInfo.class).in(LazySingleton.class);
+            if (standalone) {
+              binder.bind(RedirectFilter.class).in(LazySingleton.class);
+              binder.bind(RedirectInfo.class).to(OverlordRedirectInfo.class).in(LazySingleton.class);
+              binder.bind(JettyServerInitializer.class).toInstance(new OverlordJettyServerInitializer());
+            }
 
-            binder.bind(JettyServerInitializer.class).toInstance(new OverlordJettyServerInitializer());
             Jerseys.addResource(binder, OverlordResource.class);
             Jerseys.addResource(binder, SupervisorResource.class);
 
-            LifecycleModule.register(binder, Server.class);
+            if (standalone) {
+              LifecycleModule.register(binder, Server.class);
+            }
           }
 
           private void configureTaskStorage(Binder binder)

services/src/main/java/io/druid/cli/CoordinatorJettyServerInitializer.java

@@ -37,16 +37,20 @@
 import org.eclipse.jetty.util.resource.Resource;
 import org.eclipse.jetty.util.resource.ResourceCollection;
 
+import java.util.Properties;
+
 /**
  */
 class CoordinatorJettyServerInitializer implements JettyServerInitializer
 {
   private final DruidCoordinatorConfig config;
+  private final boolean beOverlord;
 
   @Inject
-  CoordinatorJettyServerInitializer(DruidCoordinatorConfig config)
+  CoordinatorJettyServerInitializer(DruidCoordinatorConfig config, Properties properties)
   {
     this.config = config;
+    this.beOverlord = CliCoordinator.isOverlord(properties);
   }
 
   @Override
@@ -59,10 +63,19 @@ public void initialize(Server server, Injector injector)
 
     root.addServlet(holderPwd, "/");
     if(config.getConsoleStatic() == null) {
-      ResourceCollection staticResources = new ResourceCollection(
-          Resource.newClassPathResource("io/druid/console"),
-          Resource.newClassPathResource("static")
-      );
+      ResourceCollection staticResources;
+      if (beOverlord) {
+        staticResources = new ResourceCollection(
+            Resource.newClassPathResource("io/druid/console"),
+            Resource.newClassPathResource("static"),
+            Resource.newClassPathResource("indexer_static")
+        );
+      } else {
+        staticResources = new ResourceCollection(
+            Resource.newClassPathResource("io/druid/console"),
+            Resource.newClassPathResource("static")
+        );
+      }
       root.setBaseResource(staticResources);
     } else {
       // used for console development
@@ -81,10 +94,15 @@ public void initialize(Server server, Injector injector)
     // Can't use '/*' here because of Guice and Jetty static content conflicts
     root.addFilter(GuiceFilter.class, "/info/*", null);
     root.addFilter(GuiceFilter.class, "/druid/coordinator/*", null);
+    if (beOverlord) {
+      root.addFilter(GuiceFilter.class, "/druid/indexer/*", null);
+    }
     // this will be removed in the next major release
     root.addFilter(GuiceFilter.class, "/coordinator/*", null);
 
-    root.addServlet(new ServletHolder(injector.getInstance(OverlordProxyServlet.class)), "/druid/indexer/*");
+    if (!beOverlord) {
+      root.addServlet(new ServletHolder(injector.getInstance(OverlordProxyServlet.class)), "/druid/indexer/*");
+    }
 
     HandlerList handlerList = new HandlerList();
     handlerList.setHandlers(new Handler[]{JettyServerInitUtils.getJettyRequestLogHandler(), root});