opendaylight/config/config-persister-file-xml-adapter/src/main/java/org/opendaylight/controller/config/persist/storage/file/xml/XmlFileStorageAdapter.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.config.persist.storage.file.xml;
  10
  11 import com.google.common.annotations.VisibleForTesting;
  12 import com.google.common.base.Optional;
  13 import com.google.common.base.Preconditions;
  14 import com.google.common.collect.Lists;
  15 import java.io.File;
  16 import java.io.IOException;
  17 import java.util.Collections;
  18 import java.util.List;
  19 import java.util.SortedSet;
  20 import org.opendaylight.controller.config.persist.api.ConfigSnapshotHolder;
  21 import org.opendaylight.controller.config.persist.api.Persister;
  22 import org.opendaylight.controller.config.persist.api.PropertiesProvider;
  23 import org.opendaylight.controller.config.persist.api.StorageAdapter;
  24 import org.opendaylight.controller.config.persist.storage.file.xml.model.Config;
  25 import org.opendaylight.controller.config.persist.storage.file.xml.model.ConfigSnapshot;
  26 import org.slf4j.Logger;
  27 import org.slf4j.LoggerFactory;
  28
  29 /**
  30  * StorageAdapter that stores configuration in an xml file.
  31  */
  32 public class XmlFileStorageAdapter implements StorageAdapter, Persister {
  33     private static final Logger LOG = LoggerFactory.getLogger(XmlFileStorageAdapter.class);
  34
  35     public static final String FILE_STORAGE_PROP = "fileStorage";
  36     public static final String NUMBER_OF_BACKUPS = "numberOfBackups";
  37
  38     private static Integer numberOfStoredBackups;
  39     private File storage;
  40
  41     @Override
  42     public Persister instantiate(PropertiesProvider propertiesProvider) {
  43         File storage = extractStorageFileFromProperties(propertiesProvider);
  44         LOG.debug("Using file {}", storage.getAbsolutePath());
  45         // Create file if it does not exist
  46         File parentFile = storage.getAbsoluteFile().getParentFile();
  47         if (parentFile.exists() == false) {
  48             LOG.debug("Creating parent folders {}", parentFile);
  49             parentFile.mkdirs();
  50         }
  51         if (storage.exists() == false) {
  52             LOG.debug("Storage file does not exist, creating empty file");
  53             try {
  54                 boolean result = storage.createNewFile();
  55                 if (result == false) {
  56                     throw new RuntimeException("Unable to create storage file " + storage);
  57                 }
  58             } catch (IOException e) {
  59                 throw new RuntimeException("Unable to create storage file " + storage, e);
  60             }
  61         }
  62         if (numberOfStoredBackups == 0) {
  63             throw new RuntimeException(NUMBER_OF_BACKUPS
  64                     + " property should be either set to positive value, or ommited. Can not be set to 0.");
  65         }
  66         setFileStorage(storage);
  67         return this;
  68     }
  69
  70     @VisibleForTesting
  71     public void setFileStorage(File storage) {
  72         this.storage = storage;
  73     }
  74
  75     @VisibleForTesting
  76     public void setNumberOfBackups(Integer numberOfBackups) {
  77         numberOfStoredBackups = numberOfBackups;
  78     }
  79
  80     private static File extractStorageFileFromProperties(PropertiesProvider propertiesProvider) {
  81         String fileStorageProperty = propertiesProvider.getProperty(FILE_STORAGE_PROP);
  82         Preconditions.checkNotNull(fileStorageProperty, "Unable to find " + propertiesProvider.getFullKeyForReporting(FILE_STORAGE_PROP));
  83         File result = new File(fileStorageProperty);
  84         String numberOfBackupsAsString = propertiesProvider.getProperty(NUMBER_OF_BACKUPS);
  85         if (numberOfBackupsAsString != null) {
  86             numberOfStoredBackups = Integer.valueOf(numberOfBackupsAsString);
  87         } else {
  88             numberOfStoredBackups = Integer.MAX_VALUE;
  89         }
  90         LOG.trace("Property {} set to {}", NUMBER_OF_BACKUPS, numberOfStoredBackups);
  91         return result;
  92     }
  93
  94     @Override
  95     public void persistConfig(ConfigSnapshotHolder holder) throws IOException {
  96         Preconditions.checkNotNull(storage, "Storage file is null");
  97
  98         Config cfg = Config.fromXml(storage);
  99         cfg.addConfigSnapshot(ConfigSnapshot.fromConfigSnapshot(holder), numberOfStoredBackups);
 100         cfg.toXml(storage);
 101     }
 102
 103     @Override
 104     public List<ConfigSnapshotHolder> loadLastConfigs() throws IOException {
 105         Preconditions.checkNotNull(storage, "Storage file is null");
 106
 107         if (!storage.exists()) {
 108             return Collections.emptyList();
 109         }
 110
 111         Optional<ConfigSnapshot> lastSnapshot = Config.fromXml(storage).getLastSnapshot();
 112
 113         if (lastSnapshot.isPresent()) {
 114             return Lists.newArrayList(toConfigSnapshot(lastSnapshot.get()));
 115         } else {
 116             return Collections.emptyList();
 117         }
 118     }
 119
 120
 121     public ConfigSnapshotHolder toConfigSnapshot(final ConfigSnapshot configSnapshot) {
 122         return new ConfigSnapshotHolder() {
 123             @Override
 124             public String getConfigSnapshot() {
 125                 return configSnapshot.getConfigSnapshot();
 126             }
 127
 128             @Override
 129             public SortedSet<String> getCapabilities() {
 130                 return configSnapshot.getCapabilities();
 131             }
 132
 133             @Override
 134             public String toString() {
 135                 return configSnapshot.toString();
 136             }
 137         };
 138     }
 139
 140     @Override
 141     public void close() {
 142
 143     }
 144
 145     @Override
 146     public String toString() {
 147         return "XmlFileStorageAdapter [storage=" + storage + "]";
 148     }
 149
 150 }