AMBARI-18051 - Services should be able to provide their own pre-req checks by supplying a jar file

ambari-server/pom.xml

@@ -574,6 +574,40 @@
           <argLine>-Xmx1024m -XX:MaxPermSize=512m -Xms512m</argLine>
         </configuration>
       </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>3.0.2</version>
+        <executions>
+          <execution>
+            <id>create-sample-upgrade-check-jar</id>
+            <phase>process-test-classes</phase>
+            <goals>
+              <goal>test-jar</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>target/test-classes/checks</outputDirectory>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <artifactId>maven-antrun-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>generate-test-oozie2-checks-dir</id>
+            <phase>process-test-classes</phase>
+            <goals>
+              <goal>run</goal>
+            </goals>
+            <configuration>
+              <tasks>
+                <mkdir dir="target/test-classes/extensions/EXT/0.1/services/OOZIE2/checks/tmp"/>
+              </tasks>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
       <plugin>
         <groupId>org.codehaus.mojo</groupId>
         <artifactId>exec-maven-plugin</artifactId>

ambari-server/src/main/java/org/apache/ambari/server/checks/CheckDescription.java

@@ -309,9 +309,8 @@ public class CheckDescription {
   private PrereqCheckType m_type;
   private String m_description;
   private Map<String, String> m_fails;
-  public CheckDescription(String name, PrereqCheckType type, String description,
-      Map<String, String> fails) {
-	m_name = name;
+  public CheckDescription(String name, PrereqCheckType type, String description, Map<String, String> fails) {
+    m_name = name;
     m_type = type;
     m_description = description;
     m_fails = fails;

ambari-server/src/main/java/org/apache/ambari/server/checks/UpgradeCheckRegistry.java

@@ -17,14 +17,24 @@
  */
 package org.apache.ambari.server.checks;
 
+import java.io.File;
+import java.io.FilenameFilter;
+import java.net.URL;
+import java.net.URLClassLoader;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
 
 import com.google.inject.Singleton;
+
+import org.apache.ambari.server.state.ServiceInfo;
 import org.apache.ambari.server.state.stack.UpgradePack;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.util.ClassUtils;
 
 /**
  * The {@link UpgradeCheckRegistry} contains the ordered list of all pre-upgrade
@@ -33,6 +43,7 @@ import org.apache.ambari.server.state.stack.UpgradePack;
  */
 @Singleton
 public class UpgradeCheckRegistry {
+  private static Logger LOG = LoggerFactory.getLogger(UpgradeCheckRegistry.class);
 
   /**
    * The list of upgrade checks to run through.
@@ -59,6 +70,71 @@ public class UpgradeCheckRegistry {
     return new ArrayList<AbstractCheckDescriptor>(m_upgradeChecks);
   }
 
+  public List<AbstractCheckDescriptor> getServiceLevelUpgradeChecks(UpgradePack upgradePack, Map<String, ServiceInfo> services) {
+    List<String> prerequisiteChecks = upgradePack.getPrerequisiteChecks();
+    List<String> missingChecks = new ArrayList<String>();
+    for (String prerequisiteCheck : prerequisiteChecks) {
+      if (!isRegistered(prerequisiteCheck)) {
+        missingChecks.add(prerequisiteCheck);
+      }
+    }
+
+    List<AbstractCheckDescriptor> checks = new ArrayList<>(missingChecks.size());
+    if (missingChecks.isEmpty()) {
+      return checks;
+    }
+
+    List<URL> urls = new ArrayList<URL>();
+    for (ServiceInfo service : services.values()) {
+      File dir = service.getChecksFolder();
+      File[] jars = dir.listFiles(new FilenameFilter() {
+        @Override
+        public boolean accept(File dir, String name) {
+          return name.endsWith(".jar");
+        }
+      });
+      for (File jar : jars) {
+        try {
+          URL url = jar.toURI().toURL();
+          urls.add(url);
+          LOG.debug("Adding service check jar to classpath: {}", url.toString());
+        }
+        catch (Exception e) {
+          LOG.error("Failed to add service check jar to classpath: {}", jar.getAbsolutePath(), e);
+        }
+      }
+    }
+
+    ClassLoader classLoader = new URLClassLoader(urls.toArray(new URL[urls.size()]), ClassUtils.getDefaultClassLoader());
+    for (String prerequisiteCheck : missingChecks) {
+      Class<?> clazz = null;
+      try {
+        clazz = ClassUtils.resolveClassName(prerequisiteCheck, classLoader);
+      }
+      catch (IllegalArgumentException illegalArgumentException) {
+        LOG.error("Unable to find upgrade check {}", prerequisiteCheck, illegalArgumentException);
+      }
+      try {
+        if (clazz != null) {
+          AbstractCheckDescriptor upgradeCheck = (AbstractCheckDescriptor) clazz.newInstance();
+          checks.add(upgradeCheck);
+        }
+      } catch (Exception exception) {
+        LOG.error("Unable to create upgrade check {}", prerequisiteCheck, exception);
+      }
+    }
+    return checks;
+  }
+
+  private boolean isRegistered(String prerequisiteCheck) {
+    for (AbstractCheckDescriptor descriptor: m_upgradeChecks){
+      if (prerequisiteCheck.equals(descriptor.getClass().getName())){
+        return true;
+      }
+    }
+    return false;
+  }
+
   /**
    * Gets an ordered and filtered list of the upgrade checks.
    * @param upgradePack Upgrade pack object with the list of required checks to be included

ambari-server/src/main/java/org/apache/ambari/server/controller/internal/PreUpgradeCheckResourceProvider.java

@@ -44,21 +44,26 @@ import org.apache.ambari.server.orm.entities.RepositoryVersionEntity;
 import org.apache.ambari.server.state.CheckHelper;
 import org.apache.ambari.server.state.Cluster;
 import org.apache.ambari.server.state.Clusters;
+import org.apache.ambari.server.state.ServiceInfo;
 import org.apache.ambari.server.state.UpgradeHelper;
 import org.apache.ambari.server.state.stack.PrerequisiteCheck;
+import org.apache.ambari.server.state.stack.UpgradePack;
+import org.apache.ambari.server.state.stack.upgrade.Direction;
+import org.apache.ambari.server.state.stack.upgrade.UpgradeType;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import com.google.common.collect.Sets;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
-import org.apache.ambari.server.state.stack.UpgradePack;
-import org.apache.ambari.server.state.stack.upgrade.Direction;
-import org.apache.ambari.server.state.stack.upgrade.UpgradeType;
 
 /**
  * Resource provider for pre-upgrade checks.
  */
 @StaticallyInject
 public class PreUpgradeCheckResourceProvider extends ReadOnlyResourceProvider {
+  private static Logger LOG = LoggerFactory.getLogger(PreUpgradeCheckResourceProvider.class);
 
   //----- Property ID constants ---------------------------------------------
 
@@ -89,6 +94,9 @@ public class PreUpgradeCheckResourceProvider extends ReadOnlyResourceProvider {
   @Inject
   private static Provider<UpgradeHelper> upgradeHelper;
 
+  @Inject
+  private static CheckHelper checkHelper;
+
   private static Set<String> pkPropertyIds = Collections.singleton(UPGRADE_CHECK_ID_PROPERTY_ID);
 
   public static Set<String> propertyIds = Sets.newHashSet(
@@ -113,9 +121,6 @@ public class PreUpgradeCheckResourceProvider extends ReadOnlyResourceProvider {
     }
   };
 
-  @Inject
-  private static CheckHelper checkHelper;
-
   /**
    * Constructor.
    *
@@ -185,10 +190,18 @@ public class PreUpgradeCheckResourceProvider extends ReadOnlyResourceProvider {
       }
 
       // ToDo: properly handle exceptions, i.e. create fake check with error description
-
       List<AbstractCheckDescriptor> upgradeChecksToRun = upgradeCheckRegistry.getFilteredUpgradeChecks(upgradePack);
       upgradeCheckRequest.setPrerequisiteCheckConfig(upgradePack.getPrerequisiteCheckConfig());
 
+      try {
+        // Register all the custom prechecks from the services
+        Map<String, ServiceInfo> services = getManagementController().getAmbariMetaInfo().getServices(stackName, upgradePack.getTarget());
+        List<AbstractCheckDescriptor> serviceLevelUpgradeChecksToRun = upgradeCheckRegistry.getServiceLevelUpgradeChecks(upgradePack, services);
+        upgradeChecksToRun.addAll(serviceLevelUpgradeChecksToRun);
+      } catch (AmbariException ambariException) {
+        LOG.error("Unable to register all the custom prechecks from the services", ambariException);
+      }
+
       for (PrerequisiteCheck prerequisiteCheck : checkHelper.performChecks(upgradeCheckRequest, upgradeChecksToRun)) {
         final Resource resource = new ResourceImpl(Resource.Type.PreUpgradeCheck);
         setResourceProperty(resource, UPGRADE_CHECK_ID_PROPERTY_ID, prerequisiteCheck.getId(), requestedIds);

ambari-server/src/main/java/org/apache/ambari/server/stack/CommonServiceDirectory.java

@@ -19,8 +19,6 @@
 package org.apache.ambari.server.stack;
 
 import org.apache.ambari.server.AmbariException;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import java.io.File;
 
@@ -28,10 +26,6 @@ import java.io.File;
  * Encapsulates IO operations on a common services directory.
  */
 public class CommonServiceDirectory extends ServiceDirectory {
-  /**
-   * logger instance
-   */
-  private static final Logger LOG = LoggerFactory.getLogger(CommonServiceDirectory.class);
 
   /**
    * Constructor.
@@ -62,36 +56,30 @@ public class CommonServiceDirectory extends ServiceDirectory {
 
   @Override
   /**
-   * Calculate the common service directories
-   * packageDir Format: common-services/<serviceName>/<serviceVersion>/package
-   * Example:
-   *  directory: "/var/lib/ambari-server/resources/common-services/HDFS/1.0"
-   *  packageDir: "common-services/HDFS/1.0/package"
+   * @return the service name-version (will be used for logging purposes by superclass)
    */
-  protected void calculateDirectories() {
+  public String getService() {
     File serviceVersionDir = new File(getAbsolutePath());
     File serviceDir = serviceVersionDir.getParentFile();
 
-    String serviceId = String.format("%s/%s", serviceDir.getName(), serviceVersionDir.getName());
+    String service = String.format("%s-%s", serviceDir.getName(), serviceVersionDir.getName());
+    return service;
+  }
 
-    File absPackageDir = new File(getAbsolutePath() + File.separator + PACKAGE_FOLDER_NAME);
-    if(absPackageDir.isDirectory()) {
-      packageDir = absPackageDir.getPath().substring(serviceDir.getParentFile().getParentFile().getPath().length() + 1);
-      LOG.debug(String.format("Service package folder for common service %s has been resolved to %s",
-          serviceId, packageDir));
-    } else {
-      LOG.debug(String.format("Service package folder %s for common service %s does not exist.",
-          absPackageDir, serviceId ));
-    }
+  @Override
+  /**
+   * @return the resources directory
+   */
+  protected File getResourcesDirectory() {
+    File serviceVersionDir = new File(getAbsolutePath());
+    return serviceVersionDir.getParentFile().getParentFile().getParentFile();
+  }
 
-    File absUpgradesDir = new File(getAbsolutePath() + File.separator + UPGRADES_FOLDER_NAME);
-    if(absUpgradesDir.isDirectory()) {
-      upgradesDir = absUpgradesDir;
-      LOG.debug(String.format("Service upgrades folder for common service %s has been resolved to %s",
-          serviceId, upgradesDir));
-    } else {
-      LOG.debug(String.format("Service upgrades folder %s for common service %s does not exist.",
-          absUpgradesDir, serviceId ));
-    }
+  @Override
+  /**
+   * @return the text common-services (will be used for logging purposes by superclass)
+   */
+  public String getStack() {
+    return "common-services";
   }
 }

ambari-server/src/main/java/org/apache/ambari/server/stack/ServiceDirectory.java

@@ -90,6 +90,11 @@ public abstract class ServiceDirectory extends StackDefinitionDirectory {
    */
   protected File upgradesDir;
 
+  /**
+   * checks directory path
+   */
+  protected File checksDir;
+
   /**
    * service metainfo file object representation
    */
@@ -110,6 +115,11 @@ public abstract class ServiceDirectory extends StackDefinitionDirectory {
    */
   protected static final String UPGRADES_FOLDER_NAME = "upgrades";
 
+  /**
+   * checks directory name
+   */
+  protected static final String CHECKS_FOLDER_NAME = "checks";
+
   /**
    * service metainfo file name
    */
@@ -155,6 +165,15 @@ public abstract class ServiceDirectory extends StackDefinitionDirectory {
     return upgradesDir;
   }
 
+  /**
+   * Obtain the checks directory path.
+   *
+   * @return checks directory path
+   */
+  public File getChecksDir() {
+    return checksDir;
+  }
+
   /**
    * Obtain the metrics file.
    *
@@ -238,7 +257,7 @@ public abstract class ServiceDirectory extends StackDefinitionDirectory {
    * Parse the service directory.
    */
   protected void parsePath() throws AmbariException {
-    calculateDirectories();
+    calculateDirectories(getStack(), getService());
     parseMetaInfoFile();
 
     File af = new File(directory, AmbariMetaInfo.SERVICE_ALERT_FILE_NAME);
@@ -268,12 +287,101 @@ public abstract class ServiceDirectory extends StackDefinitionDirectory {
 
     File themeFile = new File(directory, AmbariMetaInfo.SERVICE_THEME_FILE_NAME);
     this.themeFile = themeFile.exists() ? themeFile : null;
+
+    File checksFile = new File(directory, AmbariMetaInfo.SERVICE_THEME_FILE_NAME);
+    this.themeFile = themeFile.exists() ? themeFile : null;
   }
 
+  /**
+   * @return the service identifier required.  ex: service name for stack services or the service/version for common services
+   */
+  public abstract String getService();
+
+  /**
+   * @return the stack name/version or common-services
+   */
+  public abstract String getStack();
+
   /**
    * Calculate the service specific directories.
    */
-  protected abstract void calculateDirectories();
+  protected void calculateDirectories(String stack, String service) {
+	  calculatePackageDirectory(stack, service);
+	  calculateUpgradesDirectory(stack, service);
+	  calculateChecksDirectory(stack, service);
+  }
+
+  /**
+   * @param directoryName
+   * @param stack
+   * @param service
+   * @return the directory if it exists and is not empty
+   */
+  protected File resolveDirectory(String directoryName, String stack, String service) {
+    File directory = new File(getAbsolutePath() + File.separator + directoryName);
+    if (directory.isDirectory()) {
+      String[] files = directory.list();
+      int fileCount = files.length;
+      if (fileCount > 0) {
+        LOG.debug("Service {} folder for service {} in {} has been resolved to {}", directoryName, service, stack, directory);
+        return directory;
+      }
+      else {
+        LOG.debug("Service folder {} is empty.", directory);
+      }
+    }
+    else {
+      LOG.debug("Service folder {}does not exist.", directory);
+    }
+    return null;
+  }
+
+  /**
+   * @param directoryName
+   * @param stack
+   * @param service
+   * @return the relative path of the directory if it exists and is not empty
+   */
+  protected String resolveRelativeDirectoryPathString(File resourcesDir, String directoryName, String stack, String service) {
+    File dir = resolveDirectory(directoryName, stack, service);
+    if (dir != null) {
+      return dir.getPath().substring(resourcesDir.getPath().length() + 1);
+    }
+    return null;
+  }
+
+  /**
+   *  @return the resources directory
+   */
+  protected abstract File getResourcesDirectory();
+
+  /**
+   * Sets the packageDir if the path exists and is not empty
+   * @param stack
+   * @param service
+   */
+  protected void calculatePackageDirectory(String stack, String service) {
+    packageDir = resolveRelativeDirectoryPathString(getResourcesDirectory(), PACKAGE_FOLDER_NAME, stack, service);
+
+  }
+
+  /**
+   * Sets the upgradesDir if the dir exists and is not empty
+   * @param stack
+   * @param service
+   */
+  protected void calculateUpgradesDirectory(String stack, String service) {
+    upgradesDir = resolveDirectory(UPGRADES_FOLDER_NAME, stack, service);
+  }
+
+  /**
+   * Sets the checksDir if the dir exists and is not empty
+   * @param stack
+   * @param service
+   */
+  protected void calculateChecksDirectory(String stack, String service) {
+    checksDir = resolveDirectory(CHECKS_FOLDER_NAME, stack, service);
+  }
 
   /**
    * Unmarshal the metainfo file into its object representation.

ambari-server/src/main/java/org/apache/ambari/server/stack/ServiceModule.java

@@ -142,6 +142,7 @@ public class ServiceModule extends BaseModule<ServiceModule, ServiceInfo> implem
     serviceInfo.setSchemaVersion(AmbariMetaInfo.SCHEMA_VERSION_2);
     serviceInfo.setServicePackageFolder(serviceDirectory.getPackageDir());
     serviceInfo.setServiceUpgradesFolder(serviceDirectory.getUpgradesDir());
+    serviceInfo.setChecksFolder(serviceDirectory.getChecksDir());
     serviceInfo.setAdvisorFile(serviceDirectory.getAdvisorFile());
     serviceInfo.setAdvisorName(serviceDirectory.getAdvisorName(serviceInfo.getName()));
 
@@ -253,6 +254,9 @@ public class ServiceModule extends BaseModule<ServiceModule, ServiceInfo> implem
     if (serviceInfo.getRoleCommandOrder() == null) {
       serviceInfo.setRoleCommandOrder(parent.getRoleCommandOrder());
     }
+    if (serviceInfo.getChecksFolder() == null) {
+      serviceInfo.setChecksFolder(parent.getChecksFolder());
+    }
 
     mergeCustomCommands(parent.getCustomCommands(), serviceInfo.getCustomCommands());
     mergeConfigDependencies(parent);

ambari-server/src/main/java/org/apache/ambari/server/stack/StackServiceDirectory.java

@@ -28,11 +28,18 @@ import org.apache.ambari.server.state.stack.RepositoryXml;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+
 /**
  * Encapsulates IO operations on a stack service directory.
  */
 public class StackServiceDirectory extends ServiceDirectory {
 
+  /**
+   * logger instance
+   */
+  private static final Logger LOG = LoggerFactory.getLogger(StackServiceDirectory.class);
+
+
   /**
    * repository file
    */
@@ -45,12 +52,6 @@ public class StackServiceDirectory extends ServiceDirectory {
   @Nullable
   private String repoDir;
 
-
-  /**
-   * logger instance
-   */
-  private static final Logger LOG = LoggerFactory.getLogger(StackServiceDirectory.class);
-
   /**
    * Constructor.
    *
@@ -61,7 +62,6 @@ public class StackServiceDirectory extends ServiceDirectory {
     super(servicePath);
   }
 
-
   /**
    * Obtain the repository xml file if exists or null
    *
@@ -82,7 +82,6 @@ public class StackServiceDirectory extends ServiceDirectory {
     return repoDir;
   }
 
-
   @Override
   /**
    * Obtain the advisor name.
@@ -129,55 +128,35 @@ public class StackServiceDirectory extends ServiceDirectory {
 
   @Override
   /**
-   * Calculate the stack service directories.
-   * packageDir Format: stacks/<stackName>/<stackVersion>/services/<serviceName>/package
-   * Example:
-   *  directory: "/var/lib/ambari-server/resources/stacks/HDP/2.0.6/services/HDFS"
-   *  packageDir: "stacks/HDP/2.0.6/services/HDFS/package"
+   * @return the resources directory
    */
-  protected void calculateDirectories() {
+  protected File getResourcesDirectory() {
     File serviceDir = new File(getAbsolutePath());
-    File stackVersionDir = serviceDir.getParentFile().getParentFile();
-    File stackDir = stackVersionDir.getParentFile();
+    return serviceDir.getParentFile().getParentFile().getParentFile().getParentFile().getParentFile();
+  }
 
-    String stackId = String.format("%s-%s", stackDir.getName(), stackVersionDir.getName());
 
-    File absPackageDir = new File(getAbsolutePath() + File.separator + PACKAGE_FOLDER_NAME);
-    if (absPackageDir.isDirectory()) {
-      String[] files = absPackageDir.list();
-      int fileCount = files.length;
-      if (fileCount > 0) {
-        packageDir = absPackageDir.getPath().substring(stackDir.getParentFile().getParentFile().getPath().length() + 1);
-        LOG.debug("Service package folder for service %s for stack %s has been resolved to %s",
-                serviceDir.getName(), stackId, packageDir);
-      }
-      else {
-        LOG.debug("Service package folder %s for service %s for stack %s is empty.",
-                absPackageDir, serviceDir.getName(), stackId);
-      }
-    } else {
-      LOG.debug("Service package folder %s for service %s for stack %s does not exist.",
-              absPackageDir, serviceDir.getName(), stackId);
-    }
+  @Override
+  /**
+   * @return the service name (will be used for logging purposes by superclass)
+   */
+  public String getService() {
+    File serviceDir = new File(getAbsolutePath());
 
-    File absUpgradesDir = new File(getAbsolutePath() + File.separator + UPGRADES_FOLDER_NAME);
-    if (absUpgradesDir.isDirectory()) {
-      String[] files = absUpgradesDir.list();
-      int fileCount = files.length;
-      if (fileCount > 0) {
-        upgradesDir = absUpgradesDir;
-        LOG.debug("Service upgrades folder for service %s for stack %s has been resolved to %s",
-                serviceDir.getName(), stackId, packageDir);
-      }
-      else {
-        LOG.debug("Service upgrades folder %s for service %s for stack %s is empty.",
-                absUpgradesDir, serviceDir.getName(), stackId);
-      }
-    } else {
-      LOG.debug("Service upgrades folder %s for service %s for stack %s does not exist.",
-              absUpgradesDir, serviceDir.getName(), stackId);
-    }
+    return serviceDir.getName();
   }
 
+  @Override
+  /**
+   * @return the stack name-version (will be used for logging purposes by superclass)
+   */
+  public String getStack() {
+    File serviceDir = new File(getAbsolutePath());
+    File stackVersionDir = serviceDir.getParentFile().getParentFile();
+    File stackDir = stackVersionDir.getParentFile();
+
+    String stackId = String.format("%s-%s", stackDir.getName(), stackVersionDir.getName());
+    return stackId;
+  }
 
 }

ambari-server/src/main/java/org/apache/ambari/server/state/ServiceInfo.java

@@ -270,6 +270,12 @@ public class ServiceInfo implements Validable{
   @XmlTransient
   private File serviceUpgradesFolder;
 
+  /**
+   * Stores the path to the checks folder which contains prereq check jars for the given service.
+   */
+  @XmlTransient
+  private File checksFolder;
+
   public boolean isDeleted() {
     return isDeleted;
   }
@@ -600,6 +606,14 @@ public String getVersion() {
     this.serviceUpgradesFolder = serviceUpgradesFolder;
   }
 
+  public File getChecksFolder() {
+    return checksFolder;
+  }
+
+  public void setChecksFolder(File checksFolder) {
+    this.checksFolder = checksFolder;
+  }
+
   /**
    * Exposes (and initializes on first use) map of os-specific details.
    * @return  map of OS specific details keyed by family

ambari-server/src/test/java/org/apache/ambari/server/controller/internal/PreUpgradeCheckResourceProviderTest.java

@@ -0,0 +1,255 @@
+/**
+ * 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.ambari.server.controller.internal;
+
+import org.apache.ambari.server.AmbariException;
+import org.apache.ambari.server.actionmanager.ActionDBAccessor;
+import org.apache.ambari.server.api.services.AmbariMetaInfo;
+import org.apache.ambari.server.checks.AbstractCheckDescriptor;
+import org.apache.ambari.server.checks.UpgradeCheckRegistry;
+import org.apache.ambari.server.controller.AmbariManagementController;
+import org.apache.ambari.server.controller.KerberosHelper;
+import org.apache.ambari.server.controller.MaintenanceStateHelper;
+import org.apache.ambari.server.controller.RequestStatusResponse;
+import org.apache.ambari.server.controller.spi.Predicate;
+import org.apache.ambari.server.controller.spi.Request;
+import org.apache.ambari.server.controller.spi.Resource;
+import org.apache.ambari.server.controller.spi.ResourceProvider;
+import org.apache.ambari.server.controller.spi.SystemException;
+import org.apache.ambari.server.controller.utilities.PredicateBuilder;
+import org.apache.ambari.server.controller.utilities.PropertyHelper;
+import org.apache.ambari.server.events.jpa.EntityManagerCacheInvalidationEvent;
+import org.apache.ambari.server.orm.DBAccessor;
+import org.apache.ambari.server.orm.dao.RepositoryVersionDAO;
+import org.apache.ambari.server.orm.entities.RepositoryVersionEntity;
+import org.apache.ambari.server.scheduler.ExecutionScheduler;
+import org.apache.ambari.server.stack.StackManagerFactory;
+import org.apache.ambari.server.state.CheckHelper;
+import org.apache.ambari.server.state.Cluster;
+import org.apache.ambari.server.state.Clusters;
+import org.apache.ambari.server.state.Host;
+import org.apache.ambari.server.state.Service;
+import org.apache.ambari.server.state.ServiceFactory;
+import org.apache.ambari.server.state.ServiceInfo;
+import org.apache.ambari.server.state.StackId;
+import org.apache.ambari.server.state.UpgradeHelper;
+import org.apache.ambari.server.state.stack.OsFamily;
+import org.apache.ambari.server.state.stack.PrereqCheckStatus;
+import org.apache.ambari.server.state.stack.PrereqCheckType;
+import org.apache.ambari.server.state.stack.UpgradePack;
+import org.apache.ambari.server.state.stack.UpgradePack.PrerequisiteCheckConfig;
+import org.apache.ambari.server.state.stack.upgrade.Direction;
+import org.apache.ambari.server.state.stack.upgrade.UpgradeType;
+import org.easymock.EasyMock;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.io.File;
+import java.lang.reflect.Field;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import javax.persistence.EntityManager;
+
+import com.google.inject.AbstractModule;
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+import com.google.inject.Provider;
+
+import static org.easymock.EasyMock.anyBoolean;
+import static org.easymock.EasyMock.anyObject;
+import static org.easymock.EasyMock.createMock;
+import static org.easymock.EasyMock.createNiceMock;
+import static org.easymock.EasyMock.createStrictMock;
+import static org.easymock.EasyMock.eq;
+import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.expectLastCall;
+import static org.easymock.EasyMock.isNull;
+import static org.easymock.EasyMock.replay;
+import static org.easymock.EasyMock.verify;
+
+/**
+ * PreUpgradeCheckResourceProvider tests.
+ */
+public class PreUpgradeCheckResourceProviderTest {
+
+  @Test
+  public void testGetResources() throws Exception{
+    Injector injector = createInjector();
+    AmbariManagementController managementController = injector.getInstance(AmbariManagementController.class);
+
+    Clusters clusters = injector.getInstance(Clusters.class);
+    UpgradeHelper upgradeHelper = injector.getInstance(UpgradeHelper.class);
+
+    RepositoryVersionDAO repoDao = injector.getInstance(RepositoryVersionDAO.class);
+    RepositoryVersionEntity repo = createNiceMock(RepositoryVersionEntity.class);
+    UpgradePack upgradePack = createNiceMock(UpgradePack.class);
+    PrerequisiteCheckConfig config = createNiceMock(PrerequisiteCheckConfig.class);
+
+    Cluster cluster = createNiceMock(Cluster.class);
+    Service service = createNiceMock(Service.class);
+    ServiceInfo serviceInfo = createNiceMock(ServiceInfo.class);
+
+    StackId currentStackId = createNiceMock(StackId.class);
+    StackId targetStackId = createNiceMock(StackId.class);
+    ServiceFactory serviceFactory = createNiceMock(ServiceFactory.class);
+    AmbariMetaInfo ambariMetaInfo = createNiceMock(AmbariMetaInfo.class);
+
+    Map<String, Service> allServiceMap = new HashMap<String, Service>();
+    allServiceMap.put("Service100", service);
+    Map<String, ServiceInfo> allServiceInfoMap = new HashMap<String, ServiceInfo>();
+    allServiceInfoMap.put("Service100", serviceInfo);
+
+    // set expectations
+    expect(managementController.getClusters()).andReturn(clusters).anyTimes();
+    expect(managementController.getAmbariMetaInfo()).andReturn(ambariMetaInfo).anyTimes();
+    expect(managementController.getServiceFactory()).andReturn(serviceFactory).anyTimes();
+
+    expect(clusters.getCluster("Cluster100")).andReturn(cluster).anyTimes();
+    expect(cluster.getServices()).andReturn(allServiceMap).anyTimes();
+    expect(cluster.getService("Service100")).andReturn(service).anyTimes();
+    expect(cluster.getCurrentStackVersion()).andReturn(currentStackId).anyTimes();
+
+    expect(currentStackId.getStackName()).andReturn("Stack100").anyTimes();
+    expect(currentStackId.getStackVersion()).andReturn("1.0").anyTimes();
+    expect(targetStackId.getStackName()).andReturn("Stack100").anyTimes();
+    expect(targetStackId.getStackVersion()).andReturn("1.1").anyTimes();
+
+    expect(repoDao.findByStackNameAndVersion("Stack100", "Repo100")).andReturn(repo).anyTimes();
+    expect(repo.getStackId()).andReturn(targetStackId).atLeastOnce();
+    expect(upgradeHelper.suggestUpgradePack("Cluster100", "1.0", "Repo100", Direction.UPGRADE, UpgradeType.NON_ROLLING, "upgrade_pack11")).andReturn(upgradePack);
+
+    List<AbstractCheckDescriptor> upgradeChecksToRun = new LinkedList<AbstractCheckDescriptor>();
+    List<String> prerequisiteChecks = new LinkedList<String>();
+    prerequisiteChecks.add("org.apache.ambari.server.sample.checks.SampleServiceCheck");
+    expect(upgradePack.getPrerequisiteCheckConfig()).andReturn(config);
+    expect(upgradePack.getPrerequisiteChecks()).andReturn(prerequisiteChecks).anyTimes();
+    expect(upgradePack.getTarget()).andReturn("1.1").anyTimes();
+
+    expect(ambariMetaInfo.getServices("Stack100", "1.1")).andReturn(allServiceInfoMap).anyTimes();
+    String checks = ClassLoader.getSystemClassLoader().getResource("checks").getPath();
+    expect(serviceInfo.getChecksFolder()).andReturn(new File(checks));
+
+    // replay
+    replay(managementController, clusters, cluster, service, serviceInfo, repoDao, repo, upgradeHelper,
+        ambariMetaInfo, upgradePack, config, currentStackId, targetStackId, serviceFactory);
+
+    ResourceProvider provider = getPreUpgradeCheckResourceProvider(managementController, injector);
+    // create the request
+    Request request = PropertyHelper.getReadRequest(new HashSet<String>());
+    PredicateBuilder builder = new PredicateBuilder();
+    Predicate predicate = builder.property(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_CLUSTER_NAME_PROPERTY_ID).equals("Cluster100").and()
+        .property(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_UPGRADE_PACK_PROPERTY_ID).equals("upgrade_pack11").and()
+        .property(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_UPGRADE_TYPE_PROPERTY_ID).equals(UpgradeType.NON_ROLLING).and()
+        .property(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_REPOSITORY_VERSION_PROPERTY_ID).equals("Repo100").toPredicate();
+
+
+    System.out.println("PreUpgradeCheckResourceProvider - " + provider);
+    Set<Resource> resources = Collections.emptySet();
+    try {
+      resources = provider.getResources(request, predicate);
+    }
+    catch (Exception e) {
+      e.printStackTrace();
+    }
+
+    Assert.assertEquals(1, resources.size());
+    for (Resource resource : resources) {
+      String id = (String) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_ID_PROPERTY_ID);
+      Assert.assertEquals("SAMPLE_SERVICE_CHECK", id);
+      String description = (String) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_CHECK_PROPERTY_ID);
+      Assert.assertEquals("Sample service check description.", description);
+      PrereqCheckStatus status = (PrereqCheckStatus) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_STATUS_PROPERTY_ID);
+      Assert.assertEquals(PrereqCheckStatus.FAIL, status);
+      String reason = (String) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_REASON_PROPERTY_ID);
+      Assert.assertEquals("Sample service check always fails.", reason);
+      PrereqCheckType checkType = (PrereqCheckType) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_CHECK_TYPE_PROPERTY_ID);
+      Assert.assertEquals(PrereqCheckType.HOST, checkType);
+      String clusterName = (String) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_CLUSTER_NAME_PROPERTY_ID);
+      Assert.assertEquals("Cluster100", clusterName);
+      UpgradeType upgradeType = (UpgradeType) resource.getPropertyValue(PreUpgradeCheckResourceProvider.UPGRADE_CHECK_UPGRADE_TYPE_PROPERTY_ID);
+      Assert.assertEquals(UpgradeType.NON_ROLLING, upgradeType);
+    }
+
+    // verify
+    verify(managementController, clusters, cluster, service, serviceInfo, repoDao, repo, upgradeHelper,
+            ambariMetaInfo, upgradePack, config, currentStackId, targetStackId, serviceFactory);
+  }
+
+  /**
+   * This factory method creates PreUpgradeCheckResourceProvider using the mock managementController
+   */
+  public PreUpgradeCheckResourceProvider getPreUpgradeCheckResourceProvider(AmbariManagementController managementController, Injector injector) throws  AmbariException {
+    //UpgradeHelper upgradeHelper = injector.getInstance(UpgradeHelper.class);
+    //injector.injectMembers(upgradeHelper);
+    PreUpgradeCheckResourceProvider provider = new PreUpgradeCheckResourceProvider(managementController);
+    return provider;
+  }
+
+  static class TestClustersProvider implements Provider<Clusters> {
+    private static Clusters clusters = createNiceMock(Clusters.class);
+
+    @Override
+    public Clusters get() {
+      return clusters;
+    }
+  }
+
+  static class TestUpgradeHelperProvider implements Provider<UpgradeHelper> {
+    private static UpgradeHelper upgradeHelper = createNiceMock(UpgradeHelper.class);
+
+    @Override
+    public UpgradeHelper get() {
+      return upgradeHelper;
+    }
+  }
+
+  private Injector createInjector() throws Exception {
+    return Guice.createInjector(new AbstractModule() {
+      @Override
+      protected void configure() {
+        Provider<Clusters> clustersProvider = new TestClustersProvider();
+        Provider<UpgradeHelper> upgradeHelperProvider = new TestUpgradeHelperProvider();
+        CheckHelper checkHelper = new CheckHelper();
+        UpgradeCheckRegistry registry = new UpgradeCheckRegistry();
+
+        bind(AmbariManagementController.class).toInstance(createNiceMock(AmbariManagementController.class));
+        bind(CheckHelper.class).toInstance(checkHelper);
+        bind(Clusters.class).toProvider(TestClustersProvider.class);
+        bind(DBAccessor.class).toInstance(createNiceMock(DBAccessor.class));
+        bind(EntityManager.class).toInstance(createNiceMock(EntityManager.class));
+        bind(OsFamily.class).toInstance(createNiceMock(OsFamily.class));
+        bind(RepositoryVersionDAO.class).toInstance(createNiceMock(RepositoryVersionDAO.class));
+        bind(StackManagerFactory.class).toInstance(createNiceMock(StackManagerFactory.class));
+        bind(UpgradeCheckRegistry.class).toInstance(registry);
+        bind(UpgradeHelper.class).toProvider(TestUpgradeHelperProvider.class);
+
+        requestStaticInjection(PreUpgradeCheckResourceProvider.class);
+      }
+    });
+  }
+
+}

ambari-server/src/test/java/org/apache/ambari/server/sample/checks/SampleServiceCheck.java

@@ -0,0 +1,52 @@
+/*
+ * 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.ambari.server.sample.checks;
+
+import org.apache.ambari.server.AmbariException;
+import org.apache.ambari.server.checks.AbstractCheckDescriptor;
+import org.apache.ambari.server.checks.CheckDescription;
+import org.apache.ambari.server.controller.PrereqCheckRequest;
+import org.apache.ambari.server.state.stack.PrereqCheckStatus;
+import org.apache.ambari.server.state.stack.PrereqCheckType;
+import org.apache.ambari.server.state.stack.PrerequisiteCheck;
+
+import com.google.common.collect.ImmutableMap;
+
+public class SampleServiceCheck extends AbstractCheckDescriptor {
+
+  public SampleServiceCheck() {
+    super(new CheckDescription("SAMPLE_SERVICE_CHECK",
+          PrereqCheckType.HOST,
+          "Sample service check description.",
+          new ImmutableMap.Builder<String, String>()
+                          .put(AbstractCheckDescriptor.DEFAULT,
+                              "Sample service check default property description.").build()));
+  }
+
+  @Override
+  public void perform(PrerequisiteCheck prerequisiteCheck, PrereqCheckRequest request) throws AmbariException {
+    prerequisiteCheck.setFailReason("Sample service check always fails.");
+    prerequisiteCheck.setStatus(PrereqCheckStatus.FAIL);
+  }
+
+  @Override
+  public boolean isStackUpgradeAllowedToBypassPreChecks() {
+    return false;
+  }
+
+}

ambari-server/src/test/java/org/apache/ambari/server/stack/ServiceModuleTest.java

@@ -436,6 +436,36 @@ public class ServiceModuleTest {
     assertEquals(kerberosDescriptorFile, child.getModuleInfo().getKerberosDescriptorFile());
   }
 
+  @Test
+  public void testResolve_UpgradeCheckDirectory() throws Exception {
+    File checks = new File("checks");
+
+    // check directory specified in child only
+    ServiceInfo info = new ServiceInfo();
+    ServiceInfo parentInfo = new ServiceInfo();
+    ServiceModule child = createServiceModule(info);
+    ServiceModule parent = createServiceModule(parentInfo);
+    child.getModuleInfo().setChecksFolder(checks);
+    resolveService(child, parent);
+    assertEquals(checks.getPath(), child.getModuleInfo().getChecksFolder().getPath());
+
+    // check directory specified in parent only
+    child = createServiceModule(info);
+    parent = createServiceModule(parentInfo);
+    parent.getModuleInfo().setChecksFolder(checks);
+    resolveService(child, parent);
+    assertEquals(checks.getPath(), child.getModuleInfo().getChecksFolder().getPath());
+
+    // check directory set in both
+    info.setChecksFolder(checks);
+    child = createServiceModule(info);
+    child.getModuleInfo().setChecksFolder(checks);
+    parent = createServiceModule(parentInfo);
+    parent.getModuleInfo().setChecksFolder(new File("other"));
+    resolveService(child, parent);
+    assertEquals(checks.getPath(), child.getModuleInfo().getChecksFolder().getPath());
+  }
+
   @Test
   public void testResolve_CustomCommands() throws Exception {
     List<CustomCommandDefinition> customCommands = new ArrayList<CustomCommandDefinition>();

ambari-server/src/test/java/org/apache/ambari/server/stack/StackManagerExtensionTest.java

@@ -29,6 +29,7 @@ import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 import java.io.File;
+import java.io.FilenameFilter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -105,6 +106,9 @@ public class StackManagerExtensionTest  {
     assertNotNull("Package dir is " + oozie.getServicePackageFolder(), oozie.getServicePackageFolder());
     assertTrue("Package dir is " + oozie.getServicePackageFolder(), oozie.getServicePackageFolder().contains("extensions/EXT/0.1/services/OOZIE2/package"));
     assertEquals(oozie.getVersion(), "3.2.0");
+    File checks = oozie.getChecksFolder();
+    assertNotNull(checks);
+    assertTrue("Checks dir is " + checks.getPath(), checks.getPath().contains("extensions/EXT/0.1/services/OOZIE2/checks"));
 
     extension = stackManager.getExtension("EXT", "0.2");
     assertNotNull("EXT 0.2's parent: " + extension.getParentExtensionVersion(), extension.getParentExtensionVersion());
@@ -114,6 +118,9 @@ public class StackManagerExtensionTest  {
     assertNotNull("Package dir is " + oozie.getServicePackageFolder(), oozie.getServicePackageFolder());
     assertTrue("Package dir is " + oozie.getServicePackageFolder(), oozie.getServicePackageFolder().contains("extensions/EXT/0.1/services/OOZIE2/package"));
     assertEquals(oozie.getVersion(), "4.0.0");
+    checks = oozie.getChecksFolder();
+    assertNotNull(checks);
+    assertTrue("Checks dir is " + checks.getPath(), checks.getPath().contains("extensions/EXT/0.1/services/OOZIE2/checks"));
 
     StackInfo stack = stackManager.getStack("HDP", "0.2");
     assertNotNull(stack.getService("OOZIE2"));