YARN-8126. Support auto-spawning of admin configured services during bootstrap of RM. Contributed by Rohith Sharma K S.

hadoop-project/src/site/site.xml

@@ -167,6 +167,7 @@
       <item name="Concepts" href="hadoop-yarn/hadoop-yarn-site/yarn-service/Concepts.html"/>
       <item name="Yarn Service API" href="hadoop-yarn/hadoop-yarn-site/yarn-service/YarnServiceAPI.html"/>
       <item name="Service Discovery" href="hadoop-yarn/hadoop-yarn-site/yarn-service/ServiceDiscovery.html"/>
+      <item name="System Services" href="hadoop-yarn/hadoop-yarn-site/yarn-service/SystemServices.html"/>
     </menu>
 
     <menu name="Hadoop Compatible File Systems" inherit="top">

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services-api/src/main/java/org/apache/hadoop/yarn/service/client/SystemServiceManagerImpl.java

@@ -92,10 +92,12 @@ public class SystemServiceManagerImpl extends AbstractService
   private Thread serviceLaucher;
 
   @VisibleForTesting
-  private int skipCounter;
+  private int badFileNameExtensionSkipCounter;
   @VisibleForTesting
   private Map<String, Integer> ignoredUserServices =
       new HashMap<>();
+  @VisibleForTesting
+  private int badDirSkipCounter;
 
   public SystemServiceManagerImpl() {
     super(SystemServiceManagerImpl.class.getName());
@@ -268,6 +270,7 @@ void scanForUserServices() throws IOException {
         } else if (launchType.getPath().getName().equals(ASYNC)) {
           scanForUserServiceDefinition(launchType.getPath(), asyncUserServices);
         } else {
+          badDirSkipCounter++;
           LOG.debug("Scanner skips for unknown dir {}.", launchType.getPath());
         }
       }
@@ -308,7 +311,7 @@ private void scanForUserServiceDefinition(Path userDirPath,
         if (!filename.endsWith(YARN_FILE_SUFFIX)) {
           LOG.info("Scanner skips for unknown file extension, filename = {}",
               filename);
-          skipCounter++;
+          badFileNameExtensionSkipCounter++;
           continue;
         }
         Service service = getServiceDefinition(serviceCache.getPath());
@@ -325,13 +328,14 @@ private void scanForUserServiceDefinition(Path userDirPath,
             LOG.warn(
                 "Ignoring service {} for the user {} as it is already present,"
                     + " filename = {}", service.getName(), userName, filename);
-          }
+          } else {
             LOG.info("Added service {} for the user {}, filename = {}",
                 service.getName(), userName, filename);
           }
         }
       }
     }
+  }
 
   private Service getServiceDefinition(Path filePath) {
     Service service = null;
@@ -375,7 +379,13 @@ Map<String, Set<Service>> getSyncUserServices() {
     return syncUserServices;
   }
 
-  @VisibleForTesting int getSkipCounter() {
+  @VisibleForTesting
-    return skipCounter;
+  int getBadFileNameExtensionSkipCounter() {
+    return badFileNameExtensionSkipCounter;
+  }
+
+  @VisibleForTesting
+  int getBadDirSkipCounter() {
+    return badDirSkipCounter;
   }
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services-api/src/test/java/org/apache/hadoop/yarn/service/client/TestSystemServiceManagerImpl.java

@@ -41,13 +41,13 @@
 /**
  * Test class for system service manager.
  */
-public class TestSystemServiceImpl {
+public class TestSystemServiceManagerImpl {
 
   private static final Logger LOG =
-      LoggerFactory.getLogger(TestSystemServiceImpl.class);
+      LoggerFactory.getLogger(TestSystemServiceManagerImpl.class);
   private SystemServiceManagerImpl systemService;
   private Configuration conf;
-  private String resourcePath = "users";
+  private String resourcePath = "system-services";
 
   private String[] users = new String[] {"user1", "user2"};
   private static Map<String, Set<String>> loadedServices = new HashMap<>();
@@ -88,7 +88,9 @@ public void testSystemServiceSubmission() throws Exception {
         ignoredUserServices.containsKey(users[0]));
     int count = ignoredUserServices.get(users[0]);
     Assert.assertEquals(1, count);
-    Assert.assertEquals(1, systemService.getSkipCounter());
+    Assert.assertEquals(1,
+        systemService.getBadFileNameExtensionSkipCounter());
+    Assert.assertEquals(1, systemService.getBadDirSkipCounter());
 
     Map<String, Set<Service>> userServices =
         systemService.getSyncUserServices();
@@ -112,7 +114,7 @@ private void verifyForScannedUserServices(
       while (iterator.hasNext()) {
         Service next = iterator.next();
         Assert.assertTrue(
-            "Service name doesn't exist in expected " + "userService "
+            "Service name doesn't exist in expected userService "
                 + serviceNames, serviceNames.contains(next.getName()));
       }
     }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services-api/src/test/resources/system-services/bad/bad.yarnfile

@@ -0,0 +1,16 @@
+{
+  "name": "bad",
+  "version": "1.0.0",
+  "components" :
+  [
+    {
+      "name": "simple",
+      "number_of_containers": 1,
+      "launch_command": "sleep 2",
+      "resource": {
+        "cpus": 1,
+        "memory": "128"
+      }
+    }
+  ]
+}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-applications/hadoop-yarn-services/hadoop-yarn-services-core/src/test/java/org/apache/hadoop/yarn/service/TestSystemServiceManager.java

@@ -1,156 +0,0 @@
-/**
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF 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 org.apache.hadoop.yarn.service;
-
-import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.registry.client.api.RegistryOperations;
-import org.apache.hadoop.yarn.api.records.ApplicationId;
-import org.apache.hadoop.yarn.service.api.records.Artifact;
-import org.apache.hadoop.yarn.service.api.records.ComponentState;
-import org.apache.hadoop.yarn.service.api.records.Service;
-import org.apache.hadoop.yarn.service.api.records.ServiceState;
-import org.apache.hadoop.yarn.service.exceptions.SliderException;
-import org.apache.hadoop.yarn.service.registry.YarnRegistryViewForProviders;
-import org.apache.hadoop.yarn.service.utils.ServiceApiUtil;
-import org.junit.Assert;
-import org.junit.Rule;
-import org.junit.Test;
-
-import java.io.IOException;
-import java.util.Map;
-
-import static org.mockito.Mockito.mock;
-
-/**
- * Tests for {@link ServiceManager}.
- */
-public class TestSystemServiceManager {
-
-  @Rule
-  public ServiceTestUtils.ServiceFSWatcher rule =
-      new ServiceTestUtils.ServiceFSWatcher();
-
-  @Test
-  public void testUpgrade() throws IOException, SliderException {
-    ServiceManager serviceManager = createTestServiceManager("testUpgrade");
-    upgrade(serviceManager, "v2", false);
-    Assert.assertEquals("service not upgraded", ServiceState.UPGRADING,
-        serviceManager.getServiceSpec().getState());
-  }
-
-  @Test
-  public void testRestartNothingToUpgrade()
-      throws IOException, SliderException {
-    ServiceManager serviceManager = createTestServiceManager("testRestart");
-    upgrade(serviceManager, "v2", false);
-
-    //make components stable
-    serviceManager.getServiceSpec().getComponents().forEach(comp -> {
-      comp.setState(ComponentState.STABLE);
-    });
-    serviceManager.handle(new ServiceEvent(ServiceEventType.START));
-    Assert.assertEquals("service not re-started", ServiceState.STABLE,
-        serviceManager.getServiceSpec().getState());
-  }
-
-  @Test
-  public void testRestartWithPendingUpgrade()
-      throws IOException, SliderException {
-    ServiceManager serviceManager = createTestServiceManager("testRestart");
-    upgrade(serviceManager, "v2", true);
-    serviceManager.handle(new ServiceEvent(ServiceEventType.START));
-    Assert.assertEquals("service should still be upgrading",
-        ServiceState.UPGRADING, serviceManager.getServiceSpec().getState());
-  }
-
-
-  private void upgrade(ServiceManager service, String version,
-      boolean upgradeArtifact)
-      throws IOException, SliderException {
-    Service upgradedDef = ServiceTestUtils.createExampleApplication();
-    upgradedDef.setName(service.getName());
-    upgradedDef.setVersion(version);
-    if (upgradeArtifact) {
-      Artifact upgradedArtifact = createTestArtifact("2");
-      upgradedDef.getComponents().forEach(component -> {
-        component.setArtifact(upgradedArtifact);
-      });
-    }
-    writeUpgradedDef(upgradedDef);
-    ServiceEvent upgradeEvent = new ServiceEvent(ServiceEventType.UPGRADE);
-    upgradeEvent.setVersion("v2");
-    service.handle(upgradeEvent);
-  }
-
-  private ServiceManager createTestServiceManager(String name)
-      throws IOException {
-    ServiceContext context = new ServiceContext();
-    context.service = createBaseDef(name);
-    context.fs = rule.getFs();
-
-    context.scheduler = new ServiceScheduler(context) {
-      @Override
-      protected YarnRegistryViewForProviders createYarnRegistryOperations(
-          ServiceContext context, RegistryOperations registryClient) {
-        return mock(YarnRegistryViewForProviders.class);
-      }
-    };
-
-    context.scheduler.init(rule.getConf());
-
-    Map<String, org.apache.hadoop.yarn.service.component.Component>
-        componentState = context.scheduler.getAllComponents();
-    context.service.getComponents().forEach(component -> {
-      componentState.put(component.getName(),
-          new org.apache.hadoop.yarn.service.component.Component(component,
-              1L, context));
-    });
-    return new ServiceManager(context);
-  }
-
-  static Service createBaseDef(String name) {
-    ApplicationId applicationId = ApplicationId.newInstance(
-        System.currentTimeMillis(), 1);
-    Service serviceDef = ServiceTestUtils.createExampleApplication();
-    serviceDef.setId(applicationId.toString());
-    serviceDef.setName(name);
-    serviceDef.setState(ServiceState.STARTED);
-    Artifact artifact = createTestArtifact("1");
-
-    serviceDef.getComponents().forEach(component ->
-        component.setArtifact(artifact));
-    return serviceDef;
-  }
-
-  static Artifact createTestArtifact(String artifactId) {
-    Artifact artifact = new Artifact();
-    artifact.setId(artifactId);
-    artifact.setType(Artifact.TypeEnum.TARBALL);
-    return artifact;
-  }
-
-  private void writeUpgradedDef(Service upgradedDef)
-      throws IOException, SliderException {
-    Path upgradePath = rule.getFs().buildClusterUpgradeDirPath(
-        upgradedDef.getName(), upgradedDef.getVersion());
-    ServiceApiUtil.createDirAndPersistApp(rule.getFs(), upgradePath,
-        upgradedDef);
-  }
-
-}

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-site/src/site/markdown/yarn-service/SystemServices.md

@@ -0,0 +1,66 @@
+<!---
+  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. See accompanying LICENSE file.
+-->
+
+# System Services
+
+## Overview
+System services are admin configured services which are auto deployed during bootstrap of ResourceManager. This would work only when API-Server is started as part of ResourceManager. Refer [Manage services on YARN](QuickStart.html#Manage_services_on_YARN_via_REST_API). This document describes how to configure and deploy system services.
+
+## Configuration
+
+| Name | Description |
+| ------------ | ------------- |
+|yarn.service.system-service.dir| FS directory path to load and deploy admin configured services. These service spec files should be kept with proper hierarchy.|
+
+## Hierarchy of FS path
+After configuring *yarn.service.system-service.dir* path, the spec files should be kept with below hierarchy.
+````
+$SYSTEM_SERVICE_DIR_PATH/<Launch-Mode>/<Users>/<Yarnfiles>.
+````
+### Launch-Mode
+Launch-Mode indicates that how the service should be deployed. Services can be auto deployed either synchronously or asynchronously.
+
+#### sync
+These services are started synchronously along with RM. This might delay a bit RM transition to active period. This is useful when deploying critical services to get started sooner.
+
+#### async
+These services are started asynchronously without impacting RM transition period.
+
+### Users
+Users are the owner of the system service who has full access to modify it. Each users can own multiple services. Note that service names are unique per user.
+
+### Yarnfiles
+YarnFiles are the spec files to launch services. These files must have .yarnfile extension otherwise those files are ignored.
+
+### Example of hierarchy to configure system services.
+
+```
+SYSTEM_SERVICE_DIR_PATH
+|---- sync
+|     |--- user1
+|     |    |---- service1.yarnfile
+|     |    |---- service2.yarnfile
+|     |--- user2
+|     |    |---- service3.yarnfile
+|     |    ....
+|     |
+|---- async
+|     |--- user3
+|     |    |---- service1.yarnfile
+|     |    |---- service2.yarnfile
+|     |--- user4
+|     |    |---- service3.yarnfile
+|     |    ....
+|     |
+```