content: /*
   * 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.stack;
  
  import java.util.ArrayList;
  import java.util.Collection;
  
  import org.apache.ambari.server.AmbariException;
  import org.apache.ambari.server.ServiceNotFoundException;
  import org.apache.ambari.server.state.Cluster;
  import org.apache.ambari.server.state.Clusters;
  import org.apache.ambari.server.state.ExtensionInfo;
  import org.apache.ambari.server.state.ServiceInfo;
  import org.apache.ambari.server.state.StackInfo;
  import org.apache.ambari.server.state.stack.ExtensionMetainfoXml;
  import org.apache.ambari.server.utils.VersionUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * An extension version is like a stack version but it contains custom services.  Linking an extension
   * version to the current stack version allows the cluster to install the custom services contained in
   * the extension version.
   */
  public class ExtensionHelper {
  
    private final static Logger LOG = LoggerFactory.getLogger(ExtensionHelper.class);
  
    public static void validateDeleteLink(Clusters clusters, StackInfo stack, ExtensionInfo extension) throws AmbariException {
      validateNotRequiredExtension(stack, extension);
      validateServicesNotInstalled(clusters, stack, extension);
    }
  
    private static void validateServicesNotInstalled(Clusters clusters, StackInfo stack, ExtensionInfo extension) throws AmbariException {
      for (Cluster cluster : clusters.getClusters().values()) {
        for (ServiceInfo service : extension.getServices()) {
          try {
            if (service != null && cluster.getService(service.getName()) != null) {
              String message = "Extension service is still installed"
                          + ", stackName=" + stack.getName()
                          + ", stackVersion=" + stack.getVersion()
                          + ", service=" + service.getName()
                          + ", extensionName=" + extension.getName()
                          + ", extensionVersion=" + extension.getVersion();
  
              throw new AmbariException(message);
            }
          }
          catch (ServiceNotFoundException e) {
            //Eat the exception
          }
        }
      }
    }
  
    public static void validateCreateLink(StackManager stackManager, StackInfo stack, ExtensionInfo extension) throws AmbariException {
      validateSupportedStackVersion(stack, extension);
      validateServiceDuplication(stackManager, stack, extension);
      validateRequiredExtensions(stack, extension);
    }
  
    public static void validateUpdateLink(StackManager stackManager, StackInfo stack, ExtensionInfo oldExtension, ExtensionInfo newExtension) throws AmbariException {
      validateSupportedStackVersion(stack, newExtension);
      validateServiceDuplication(stackManager, stack, oldExtension, newExtension);
      validateRequiredExtensions(stack, newExtension);
    }
  
    private static void validateSupportedStackVersion(StackInfo stack, ExtensionInfo extension) throws AmbariException {
      for (ExtensionMetainfoXml.Stack validStack : extension.getStacks()) {
        if (validStack.getName().equals(stack.getName())) {
          String minStackVersion = validStack.getVersion();
          if (VersionUtils.compareVersions(stack.getVersion(), minStackVersion) >= 0) {
            //Found a supported stack version
            return;
          }
        }
      }
  
      String message = "Stack is not supported by extension"
  		+ ", stackName=" + stack.getName()
  		+ ", stackVersion=" + stack.getVersion()
  		+ ", extensionName=" + extension.getName()
  		+ ", extensionVersion=" + extension.getVersion();
  
      throw new AmbariException(message);
    }
  
    private static void validateServiceDuplication(StackManager stackManager, StackInfo stack, ExtensionInfo extension) throws AmbariException {
      validateServiceDuplication(stackManager, stack, extension, extension.getServices());
    }
  
    private static void validateServiceDuplication(StackManager stackManager, StackInfo stack, ExtensionInfo oldExtension, ExtensionInfo newExtension) throws AmbariException {
      ArrayList<ServiceInfo> services = new ArrayList<>(newExtension.getServices().size());
      for (ServiceInfo service : newExtension.getServices()) {
        boolean found = false;
        for (ServiceInfo current : oldExtension.getServices()) {
          if (service.getName().equals(current.getName())) {
            found = true;
          }
        }
        if (!found) {
          services.add(service);
        }
      }
      validateServiceDuplication(stackManager, stack, newExtension, services);
    }
  
    private static void validateServiceDuplication(StackManager stackManager, StackInfo stack, ExtensionInfo extension, Collection<ServiceInfo> services) throws AmbariException {
      LOG.debug("Looking for duplicate services");
      for (ServiceInfo service : services) {
        if (service != null) {
          LOG.debug("Looking for duplicate service " + service.getName());
          ServiceInfo stackService = null;
          try {
            stackService = stack.getService(service.getName());
            if (stackService != null) {
              LOG.debug("Found service " + service.getName());
              if (isInheritedExtensionService(stackManager, stack, service.getName(), extension.getName())) {
                stackService = null;
              }
            }
          }
          catch (Exception e) {
            //Eat the exception
            LOG.error("Error validating service duplication", e);
          }
          if (stackService != null) {
            String message = "Existing service is included in extension"
                        + ", stackName=" + stack.getName()
                        + ", stackVersion=" + stack.getVersion()
                        + ", service=" + service.getName()
                        + ", extensionName=" + extension.getName()
                        + ", extensionVersion=" + extension.getVersion();
  
            throw new AmbariException(message);
          }
        }
      }
    }
  
    private static boolean isInheritedExtensionService(StackManager stackManager, StackInfo stack, String serviceName, String extensionName) {
      // Check if service is from an extension at the current stack level, if so then it isn't inherited from its parent stack version
      if (isExtensionService(stack, serviceName, extensionName)) {
        LOG.debug("Service is at requested stack/version level " + serviceName);
        return false;
      }
  
      return isExtensionService(stackManager, stack.getName(), stack.getParentStackVersion(), serviceName, extensionName);
    }
  
    private static boolean isExtensionService(StackManager stackManager, String stackName, String stackVersion, String serviceName, String extensionName) {
      LOG.debug("Checking at stack/version " + stackName + "/" + stackVersion);
      StackInfo stack = stackManager.getStack(stackName, stackVersion);
  
      if (stack == null) {
        LOG.warn("Stack/version not found " + stackName + "/" + stackVersion);
        return false;
      }
  
      if (isExtensionService(stack, serviceName, extensionName)) {
        LOG.debug("Stack/version " + stackName + "/" + stackVersion + " contains service " + serviceName);
        return true;
      }
      else {
        return isExtensionService(stackManager, stackName, stack.getParentStackVersion(), serviceName, extensionName);
      }
    }
  
    private static boolean isExtensionService(StackInfo stack, String serviceName, String extensionName) {
      ExtensionInfo extension = stack.getExtension(extensionName);
      if (extension == null) {
        LOG.debug("Extension not found " + extensionName);
        return false;
      }
  
      return extension.getService(serviceName) != null;
    }
  
    private static void validateRequiredExtensions(StackInfo stack, ExtensionInfo extension) throws AmbariException {
      for (ExtensionMetainfoXml.Extension requiredExtension : extension.getExtensions()) {
        if (requiredExtension != null) {
          String message = "Stack has not linked required extension"
                      + ", stackName=" + stack.getName()
                      + ", stackVersion=" + stack.getVersion()
                      + ", extensionName=" + extension.getName()
                      + ", extensionVersion=" + extension.getVersion()
                      + ", requiredExtensionName=" + requiredExtension.getName()
                      + ", requiredExtensionVersion=" + requiredExtension.getVersion();
          try {
            ExtensionInfo stackExtension = stack.getExtension(requiredExtension.getName());
            if (stackExtension != null) {
              String version = requiredExtension.getVersion();
              if (version.endsWith("*")) {
                version = version.substring(0, version.length() - 1);
                if (!stackExtension.getVersion().startsWith(version)) {
                  throw new AmbariException(message);
                }
              }
              else if (!stackExtension.getVersion().equals(version)) {
                throw new AmbariException(message);
              }
            }
          }
          catch (Exception e) {
            throw new AmbariException(message, e);
          }
        }
      }
    }
  
    private static void validateNotRequiredExtension(StackInfo stack, ExtensionInfo extension) throws AmbariException {
      for (ExtensionInfo stackExtension : stack.getExtensions()) {
        if (stackExtension != null) {
          for (ExtensionMetainfoXml.Extension requiredExtension : stackExtension.getExtensions()) {
            if (requiredExtension != null && requiredExtension.getName().equals(extension.getName())) {
              String message = "Stack extension is required by extension"
                          + ", stackName=" + stack.getName()
                          + ", stackVersion=" + stack.getVersion()
                          + ", extensionName=" + extension.getName()
                          + ", extensionVersion=" + extension.getVersion()
                          + ", dependentExtensionName=" + stackExtension.getName()
                          + ", dependentExtensionVersion=" + stackExtension.getVersion();
  
              throw new AmbariException(message);
            }
          }
        }
      }
    }
  
  }
  