ConfigHelper.java
/*
* Syncany, www.syncany.org
* Copyright (C) 2011-2016 Philipp C. Heckel <philipp.heckel@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.syncany.config;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.simpleframework.xml.core.Persister;
import org.syncany.config.to.ConfigTO;
import org.syncany.config.to.RepoTO;
import org.syncany.crypto.CipherUtil;
import org.syncany.crypto.SaltedSecretKey;
import org.syncany.plugins.Plugins;
import org.syncany.plugins.transfer.TransferPlugin;
/**
* The config helper provides convenience functions to load the configuration from
* the local application repo.
*
* @author Philipp C. Heckel (philipp.heckel@gmail.com)
*/
public class ConfigHelper {
private static final Logger logger = Logger.getLogger(ConfigHelper.class.getSimpleName());
/**
* Loads a {@link Config} object from the given local directory.
*
* <p>If the config file (.syncany/config.xml) does not exist, <code>null</code>
* is returned. If it does, the method tries to do the following:
* <ul>
* <li>Load the .syncany/config.xml file and load the plugin given by the config file</li>
* <li>Read .syncany/repo, decrypt it using the master key (if necessary) and load it</li>
* <li>Instantiate a {@link Config} object with the transfer objects</li>
* </ul>
*
* @return Returns an instantiated {@link Config} object, or <code>null</code> if
* the config file does not exist
* @throws ConfigException an exception if the config is invalid
*/
public static Config loadConfig(File localDir) throws ConfigException {
if (localDir == null) {
throw new ConfigException("Argument localDir cannot be null.");
}
File appDir = new File(localDir, Config.DIR_APPLICATION);
if (appDir.exists()) {
logger.log(Level.INFO, "Loading config from {0} ...", localDir);
ConfigTO configTO = ConfigHelper.loadConfigTO(localDir);
RepoTO repoTO = ConfigHelper.loadRepoTO(localDir, configTO);
String pluginId = (configTO.getTransferSettings() != null) ? configTO.getTransferSettings().getType() : null;
TransferPlugin plugin = Plugins.get(pluginId, TransferPlugin.class);
if (plugin == null) {
logger.log(Level.WARNING, "Not loading config! Plugin with id '{0}' does not exist.", pluginId);
throw new ConfigException("Plugin with id '" + pluginId + "' does not exist. Try 'sy plugin install " + pluginId + "'.");
}
logger.log(Level.INFO, "Initializing Config instance ...");
return new Config(localDir, configTO, repoTO);
}
else {
logger.log(Level.INFO, "Not loading config, app dir does not exist: {0}", appDir);
return null;
}
}
/**
* Returns true if the config.xml file exists, given a local directory.
*/
public static boolean configExists(File localDir) {
File appDir = new File(localDir, Config.DIR_APPLICATION);
File configFile = new File(appDir, Config.FILE_CONFIG);
return configFile.exists();
}
/**
* Loads the config transfer object from the local directory
* or throws an exception if the file does not exist.
*/
public static ConfigTO loadConfigTO(File localDir) throws ConfigException {
File appDir = new File(localDir, Config.DIR_APPLICATION);
File configFile = new File(appDir, Config.FILE_CONFIG);
if (!configFile.exists()) {
throw new ConfigException("Cannot find config file at "+configFile+". Try connecting to a repository using 'connect', or 'init' to create a new one.");
}
return ConfigTO.load(configFile);
}
/**
* Loads the repository transfer object from the local directory.
*/
public static RepoTO loadRepoTO(File localDir, ConfigTO configTO) throws ConfigException {
File appDir = new File(localDir, Config.DIR_APPLICATION);
File repoFile = new File(appDir, Config.FILE_REPO);
if (!repoFile.exists()) {
throw new ConfigException("Cannot find repository file at "+repoFile+". Try connecting to a repository using 'connect', or 'init' to create a new one.");
}
try {
if (CipherUtil.isEncrypted(repoFile)) {
return loadEncryptedRepoTO(repoFile, configTO);
}
else {
return loadPlaintextRepoTO(repoFile, configTO);
}
}
catch (Exception e) {
throw new ConfigException("Cannot load repo file: "+e.getMessage(), e);
}
}
/**
* Helper method to find the local sync directory, starting from a path equal
* or inside the local sync directory. If the starting path is not inside or equal
* to the local directory, <code>null</code> is returned.
*
* <p>To find the local directory, the method looks for a file named
* "{@link Config#DIR_APPLICATION}/{@link Config#FILE_CONFIG}". If it is found, it stops.
* If not, it continues looking in the parent directory.
*
* <p>Example: If /home/user/Syncany is the local sync directory and /home/user/NotSyncany
* is not a local directory, the method will return the following:
*
* <ul>
* <li>findLocalDirInPath(/home/user/Syncany) -> /home/user/Syncany</li>
* <li>findLocalDirInPath(/home/user/Syncany/some/subfolder) -> /home/user/Syncany</li>
* <li>findLocalDirInPath(/home/user/NotSyncany) ->null</li>
* </ul>
*
* @param startingPath Path to start the search from
* @return Returns the local directory (if found), or <code>null</code> otherwise
*/
public static File findLocalDirInPath(File startingPath) {
try {
File currentSearchFolder = startingPath.getCanonicalFile();
while (currentSearchFolder != null) {
File possibleAppDir = new File(currentSearchFolder, Config.DIR_APPLICATION);
File possibleConfigFile = new File(possibleAppDir, Config.FILE_CONFIG);
if (possibleAppDir.exists() && possibleConfigFile.exists()) {
return possibleAppDir.getParentFile().getCanonicalFile();
}
currentSearchFolder = currentSearchFolder.getParentFile();
}
return null;
}
catch (IOException e) {
throw new RuntimeException("Unable to determine local directory starting from: "+startingPath, e);
}
}
private static RepoTO loadPlaintextRepoTO(File repoFile, ConfigTO configTO) throws Exception {
logger.log(Level.INFO, "Loading (unencrypted) repo file from {0} ...", repoFile);
return new Persister().read(RepoTO.class, repoFile);
}
private static RepoTO loadEncryptedRepoTO(File repoFile, ConfigTO configTO) throws Exception {
logger.log(Level.INFO, "Loading encrypted repo file from {0} ...", repoFile);
SaltedSecretKey masterKey = configTO.getMasterKey();
if (masterKey == null) {
throw new ConfigException("Repo file is encrypted, but master key not set in config file.");
}
String repoFileStr = new String(CipherUtil.decrypt(new FileInputStream(repoFile), masterKey));
return new Persister().read(RepoTO.class, repoFileStr);
}
}