org.syncany.plugins.googledrive.GoogledriveTransferManager.java Source code

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Here is the source code for org.syncany.plugins.googledrive.GoogledriveTransferManager.java

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/*
 * Syncany, www.syncany.org
 * Copyright (C) 2011-2014 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.plugins.googledrive;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.syncany.config.Config;
import org.syncany.plugins.transfer.AbstractTransferManager;
import org.syncany.plugins.transfer.StorageException;
import org.syncany.plugins.transfer.StorageMoveException;
import org.syncany.plugins.transfer.TransferManager;
import org.syncany.plugins.transfer.files.RemoteFile;
import org.syncany.plugins.transfer.files.SyncanyRemoteFile;

import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.http.FileContent;
import com.google.api.client.http.GenericUrl;
import com.google.api.client.http.HttpResponse;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.Drive.Files;
import com.google.api.services.drive.model.FileList;
import com.google.api.services.drive.model.ParentReference;
import com.google.api.services.drive.model.Property;

/**
 * Implements a {@link TransferManager} based on an Google Drive storage backend for the
 * {@link GoogledriveTransferPlugin}.
 * <p/>
 * <p>Using an {@link GoogledriveTransferSettings}, the transfer manager is configured and uses
 * a Google Drive folder to store the Syncany repository data. 
 * <p/>
 * <p>All operations are auto-connected, i.e. a connection is automatically
 * established.
 *
 * @author Darryl Tam <contact@darryltam.com>
 * 
 */
public class GoogledriveTransferManager extends AbstractTransferManager {

    private static final Logger logger = Logger.getLogger(GoogledriveTransferManager.class.getSimpleName());

    private final Drive drive;

    private static final String APPLICATION_CONTENT_TYPE = "application/x-syncany";
    private static final String FOLDER_CONTENT_TYPE = "application/vnd.google-apps.folder";
    private static final String APPLICATION_NAME = "Syncany Google Drive Client";
    private static final String FILE_DESCRIPTION = "Syncany Google Drive Repository file";

    private static final String NOT_TRASHED = "trashed=false";

    private static final String REMOTE_FILETYPE_PROPERTIES_KEY = "org.syncany.remotefiletype";

    private final GoogledriveTransferSettings settings;

    public GoogledriveTransferManager(GoogledriveTransferSettings settings, Config config) throws StorageException {
        super(settings, config);

        this.settings = settings;

        GoogleCredential credentials = new GoogleCredential.Builder()
                .setTransport(GoogledriveTransferPlugin.HTTP_TRANSPORT)
                .setJsonFactory(GoogledriveTransferPlugin.JSON_FACTORY)
                .setClientSecrets(GoogledriveTransferPlugin.CLIENT_ID, GoogledriveTransferPlugin.CLIENT_SECRET)
                .build().setRefreshToken(settings.getRefreshToken());

        //TODO: [medium] Find a way to re-authenticate token if it has expired/been revoked
        if (settings.isSetupComplete()) {
            try {
                credentials.refreshToken();
            } catch (IOException e) {
                logger.log(Level.SEVERE, "Unable to refresh token.  It may be expired or revoked.",
                        new Object[] { settings.getRefreshToken() });
                throw new StorageException("Unable to refresh token.  It may be expired or revoked.");
            }
        }

        this.drive = new Drive.Builder(GoogledriveTransferPlugin.HTTP_TRANSPORT,
                GoogledriveTransferPlugin.JSON_FACTORY, credentials).setApplicationName(APPLICATION_NAME).build();
    }

    @Override
    public void connect() throws StorageException {
        try {
            logger.log(Level.INFO, "Using Google Drive account from {0}",
                    new Object[] { drive.about().get().execute().getName() });
        } catch (Exception e) {
            throw new StorageException("Unable to connect to googledrive", e);
        }
    }

    @Override
    public void disconnect() {
        // Nothing
    }

    @Override
    public void init(boolean createIfRequired) throws StorageException {
        connect();

        try {
            if (!testTargetExists() && createIfRequired) {
                settings.setPathId(createFolder(settings.getPath(), null).getId());
            }
            settings.setSetupComplete(true);
        } catch (IOException e) {
            throw new StorageException("init: Cannot create required directory", e);
        } finally {
            disconnect();
        }
    }

    private com.google.api.services.drive.model.File createFolder(String path, String parentId) throws IOException {
        return createFolder(splitPath(path), parentId);
    }

    private com.google.api.services.drive.model.File createFolder(String[] path, String parentId)
            throws IOException {

        com.google.api.services.drive.model.File result = null;

        for (String curPath : path) {
            try {
                com.google.api.services.drive.model.File body = new com.google.api.services.drive.model.File();
                body.setTitle(curPath).setMimeType(FOLDER_CONTENT_TYPE);

                if (parentId != null) {
                    body.setParents(Arrays.asList(new ParentReference().setId(parentId)));
                }

                result = drive.files().insert(body).execute();
                parentId = result.getId();
            } catch (IOException e) {
                throw e;
            }
        }
        return result;
    }

    private String[] splitPath(String path) {
        // Assume / are directory separators except when escaped with a \, all \ are interpreted as a \ if not escaping a /,
        ArrayList<String> splitList = new ArrayList<String>();
        int curIndex = 0;
        while (curIndex != -1) {
            curIndex = path.indexOf('/', curIndex);
            if (curIndex >= 0) {
                if (curIndex != 0) {
                    if (path.charAt(curIndex - 1) == '\\') {
                        // escaped
                        curIndex++;
                        continue;
                    }
                }
                String addString = path.substring(0, curIndex).replace("\\/", "/");
                if (!addString.isEmpty()) {
                    splitList.add(addString);
                }
                path = path.substring(curIndex + 1);
            }
        }
        String addString = path.replace("\\/", "/");
        if (!addString.isEmpty()) {
            splitList.add(path.replace("\\/", "/"));
        }
        return splitList.toArray(new String[splitList.size()]);
    }

    private String quoteString(String str) {
        return "'" + str.replace("'", "\\'") + "'";
    }

    private String assembleSearch(String... arguments) {
        String result = "";
        for (String argument : arguments) {
            if (result.length() != 0 && argument.length() != 0) {
                result += " and ";
            }
            result += argument;
        }
        return result;
    }

    @Override
    public void download(RemoteFile remoteFile, File localFile) throws StorageException {
        if (!remoteFile.getName().equals(".") && !remoteFile.getName().equals("..")) {
            try {
                // Download file
                File tempFile = createTempFile(localFile.getName());

                if (logger.isLoggable(Level.INFO)) {
                    logger.log(Level.INFO, "Google Drive: Downloading {0} to temp file {1}",
                            new Object[] { remoteFile.getName(), tempFile });
                }

                com.google.api.services.drive.model.File curFile = getRemoteFile(remoteFile);

                if (curFile.getDownloadUrl() == null || curFile.getDownloadUrl().length() == 0) {
                    throw new StorageException("Cannot get download URL for file");
                }

                HttpResponse resp = drive.getRequestFactory()
                        .buildGetRequest(new GenericUrl(curFile.getDownloadUrl())).execute();

                OutputStream tempFOS = new FileOutputStream(tempFile);

                InputStream tempFIS = resp.getContent();
                IOUtils.copy(tempFIS, tempFOS);

                tempFIS.close();
                tempFOS.close();

                // Move file
                if (logger.isLoggable(Level.INFO)) {
                    logger.log(Level.INFO, "Google Drive: Renaming temp file {0} to file {1}",
                            new Object[] { tempFile, localFile });
                }

                localFile.delete();
                FileUtils.moveFile(tempFile, localFile);
                tempFile.delete();
            } catch (IOException | StorageException ex) {
                logger.log(Level.SEVERE, "Error while downloading file " + remoteFile.getName(), ex);
                throw new StorageException(ex);
            }
        }
    }

    private java.util.List<com.google.api.services.drive.model.File> getRemoteFiles(RemoteFile remoteFile)
            throws StorageException {
        return getRemoteFileHelper(remoteFile, remoteFile.getClass());
    }

    private <T extends RemoteFile> java.util.List<com.google.api.services.drive.model.File> getRemoteFiles(
            Class<T> remoteFileClass) throws StorageException {
        return getRemoteFileHelper(null, remoteFileClass);
    }

    private <T extends RemoteFile> java.util.List<com.google.api.services.drive.model.File> getRemoteFileHelper(
            RemoteFile remoteFile, Class<T> remoteFileClass) throws StorageException {
        try {
            ArrayList<String> requestList = new ArrayList<String>();
            requestList.add(NOT_TRASHED);

            if (remoteFile != null) {
                requestList.add("title=" + quoteString(remoteFile.getName()));
            }

            requestList.add(quoteString(settings.getPathId()) + " in parents");

            requestList.add("properties has { key=" + quoteString(REMOTE_FILETYPE_PROPERTIES_KEY) + " and value="
                    + quoteString(remoteFileClass.getCanonicalName()) + " and visibility='PUBLIC'" + " }");

            String[] requestArray = requestList.toArray(new String[requestList.size()]);

            Files.List request = drive.files().list().setQ(assembleSearch(requestArray));

            java.util.List<com.google.api.services.drive.model.File> result = new ArrayList<com.google.api.services.drive.model.File>();

            //Assemble list of all files matching name and in folder 
            do {
                try {
                    FileList files = request.execute();

                    result.addAll(files.getItems());
                    request.setPageToken(files.getNextPageToken());
                } catch (IOException ex) {
                    logger.log(Level.WARNING, "getRemoteFileHelper: Error occurred.", ex);
                    request.setPageToken(null);
                }
            } while (request.getPageToken() != null && request.getPageToken().length() > 0);

            return result;

        } catch (Exception ex) {
            logger.log(Level.WARNING, "getRemoteFileHelper: Target does NOT exist, error occurred.", ex);
            throw new StorageException(ex);
        }
    }

    private com.google.api.services.drive.model.File getRemoteFile(RemoteFile remoteFile) throws StorageException {
        java.util.List<com.google.api.services.drive.model.File> fileList = getRemoteFiles(remoteFile);
        if (fileList.isEmpty()) {
            logger.log(Level.WARNING, "getRemoteFile: Target does NOT exist, error occurred.");
            throw new StorageException("getRemoteFile: Target does NOT exist, error occurred.");
        } else if (fileList.size() > 1) {
            logger.log(Level.WARNING, "getRemoteFile: " + fileList.size() + " files exist.");
            throw new StorageException("getRemoteFile: " + fileList.size() + " files exist.");
        }
        return fileList.get(0);
    }

    @Override
    public void upload(File localFile, RemoteFile remoteFile) throws StorageException {
        try {
            if (logger.isLoggable(Level.INFO)) {
                logger.log(Level.INFO, "Google Drive: Uploading {0} to temp file {1}",
                        new Object[] { localFile, settings.getPathId() + ":" + ("temp-" + remoteFile.getName()) });
            }

            com.google.api.services.drive.model.File curFile = new com.google.api.services.drive.model.File();

            curFile.setTitle("temp-" + remoteFile.getName()).setDescription(FILE_DESCRIPTION)
                    .setMimeType(APPLICATION_CONTENT_TYPE)
                    .setParents(Arrays.asList(new ParentReference().setId(settings.getPathId())))
                    .setProperties(Arrays.asList(new Property().setKey(REMOTE_FILETYPE_PROPERTIES_KEY)
                            .setValue(remoteFile.getClass().getCanonicalName()).setVisibility("PUBLIC")));

            FileContent mediaContent = new FileContent(APPLICATION_CONTENT_TYPE, localFile);
            curFile = drive.files().insert(curFile, mediaContent).execute();

            if (logger.isLoggable(Level.INFO)) {
                logger.log(Level.INFO, "Google Drive: Renaming temp file {0} to file {1}",
                        new Object[] { "temp-" + remoteFile.getName(), remoteFile.getName() });
            }

            curFile.setTitle(remoteFile.getName());
            Files.Patch patchRequest = drive.files().patch(curFile.getId(), curFile);
            patchRequest.setFields("title");
            curFile = patchRequest.execute();

            if (curFile == null) {
                if (logger.isLoggable(Level.WARNING)) {
                    logger.log(Level.WARNING, "Google Drive: Renaming temp file failed");
                }
                throw new StorageException("Renaming Failed");
            }
        } catch (StorageException | IOException ex) {
            logger.log(Level.SEVERE, "Could not upload file " + localFile + " to " + remoteFile.getName(), ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public boolean delete(RemoteFile remoteFile) throws StorageException {
        try {
            java.util.List<com.google.api.services.drive.model.File> curFiles = getRemoteFiles(remoteFile);
            if (curFiles.isEmpty()) {
                return true;
            }

            for (com.google.api.services.drive.model.File curFile : curFiles) {
                drive.files().delete(curFile.getId()).execute();
            }
            return true;
        } catch (IOException e) {
            logger.log(Level.SEVERE, "Could not delete file " + remoteFile.getName(), e);
            throw new StorageException(e);
        }
    }

    @Override
    public void move(RemoteFile sourceFile, RemoteFile targetFile) throws StorageException {

        try {
            com.google.api.services.drive.model.File curSourceFile = getRemoteFile(sourceFile);
            java.util.List<com.google.api.services.drive.model.File> curTargetFiles = getRemoteFiles(targetFile);

            if (curTargetFiles.size() > 1) {
                throw new IOException("Multiple destination files matching criteria");
            }

            com.google.api.services.drive.model.File curTargetFile = null;

            if (!curTargetFiles.isEmpty()) {
                curTargetFile = curTargetFiles.get(0);
            }

            //Rename file
            if (!sourceFile.getName().equals(targetFile.getName())) {
                if (logger.isLoggable(Level.INFO)) {
                    logger.log(Level.INFO, "Google Drive: Renaming file {0} to file {1}",
                            new Object[] { sourceFile.getName(), targetFile.getName() });
                }
                com.google.api.services.drive.model.File patchFile = new com.google.api.services.drive.model.File();
                patchFile.setTitle(targetFile.getName());
                patchFile.setProperties(Arrays.asList(new Property().setKey(REMOTE_FILETYPE_PROPERTIES_KEY)
                        .setValue(targetFile.getClass().getCanonicalName()).setVisibility("PUBLIC")));
                patchFile = drive.files().patch(curSourceFile.getId(), patchFile).setFields("title,properties")
                        .execute();

                if (patchFile == null) {
                    if (logger.isLoggable(Level.WARNING)) {
                        logger.log(Level.WARNING, "Google Drive: Renaming temp file failed");
                    }
                    throw new StorageException("Renaming Failed");
                }
                if (curTargetFile != null) {
                    //delete destination if target exists
                    drive.files().delete(curTargetFile.getId()).execute();
                }
            }

        } catch (IOException e) {
            logger.log(Level.SEVERE,
                    "Could not rename file " + sourceFile.getName() + " to " + targetFile.getName(), e);
            throw new StorageMoveException(
                    "Could not rename file " + sourceFile.getName() + " to " + targetFile.getName(), e);
        }
    }

    @Override
    public <T extends RemoteFile> Map<String, T> list(Class<T> remoteFileClass) throws StorageException {
        try {
            java.util.List<com.google.api.services.drive.model.File> listing = getRemoteFiles(remoteFileClass);

            // Create RemoteFile objects
            Map<String, T> remoteFiles = new HashMap<String, T>();

            for (com.google.api.services.drive.model.File child : listing) {
                try {
                    T remoteFile = RemoteFile.createRemoteFile(child.getTitle(), remoteFileClass);
                    remoteFiles.put(child.getTitle(), remoteFile);
                } catch (Exception e) {
                    logger.log(Level.INFO,
                            "Cannot create instance of " + remoteFileClass.getSimpleName() + " for file "
                                    + child.getTitle() + "; maybe invalid file name pattern. Ignoring file.");
                }
            }

            return remoteFiles;
        } catch (Exception ex) {
            disconnect();
            logger.log(Level.SEVERE, "Unable to list Google Drive directory.", ex);
            throw new StorageException(ex);
        }
    }

    @Override
    public boolean testTargetCanWrite() {
        try {
            if (testTargetExists()) {
                String temporaryFilename = "syncany-write-test";
                File tempFile = File.createTempFile(temporaryFilename, "tmp");

                // Write
                com.google.api.services.drive.model.File curFile = new com.google.api.services.drive.model.File();
                curFile.setTitle(temporaryFilename).setDescription(FILE_DESCRIPTION)
                        .setMimeType(APPLICATION_CONTENT_TYPE)
                        .setParents(Arrays.asList(new ParentReference().setId(settings.getPathId())));
                FileContent mediaContent = new FileContent(APPLICATION_CONTENT_TYPE, tempFile);
                curFile = drive.files().insert(curFile, mediaContent).execute();

                //Delete
                tempFile.delete();
                drive.files().delete(curFile.getId()).execute();

                logger.log(Level.INFO, "testTargetCanWrite: Can write, test file created/deleted successfully.");
                return true;
            } else {
                logger.log(Level.INFO, "testTargetCanWrite: Can NOT write, target does not exist.");
                return false;
            }
        } catch (IOException e) {
            logger.log(Level.INFO, "testTargetCanWrite: Can NOT write to target.", e);
            return false;
        }
    }

    @Override
    public boolean testTargetExists() {
        try {

            String[] splitPath = splitPath(settings.getPath());
            String parent = null;
            for (String pathElement : splitPath) {
                String requestSearch = assembleSearch(NOT_TRASHED, "mimeType=" + quoteString(FOLDER_CONTENT_TYPE),
                        "title=" + quoteString(pathElement));
                if (parent != null) {
                    requestSearch = assembleSearch(requestSearch, quoteString(parent) + " in parents");
                }
                Files.List request = drive.files().list().setQ(requestSearch);
                FileList files = request.execute();

                if (files.getItems().isEmpty()) {
                    logger.log(Level.INFO, "testTargetExists: Target does NOT exist.");
                    return false;
                } else if (files.getItems().size() != 1) {
                    logger.log(Level.WARNING,
                            "testTargetExists: Target exists, but there are multiple folders with the same name.");
                    return false;
                }
                parent = files.getItems().get(0).getId();

            }

            if (!settings.isSetupComplete()) {
                // When connecting to an existing repository, retrieve the path ids and store them
                settings.setPathId(parent);
                settings.setSetupComplete(true);
            }

            logger.log(Level.INFO, "testTargetExists: Target does exist.");
            return true;

        } catch (Exception e) {
            logger.log(Level.WARNING, "testTargetExists: Target does NOT exist, error occurred.", e);
            return false;
        }
    }

    @Override
    public boolean testTargetCanCreate() {

        try {
            if (testTargetExists()) {
                return true;
            }
            // Google Drive doesn't have per-folder permissions, so creating any folder means you can create the target
            //Note that if there's a subpath, this won't match exactly the target folder
            com.google.api.services.drive.model.File tmpFolder = new com.google.api.services.drive.model.File();
            tmpFolder.setTitle(settings.getPath()).setMimeType(FOLDER_CONTENT_TYPE);
            tmpFolder = drive.files().insert(tmpFolder).execute();
            drive.files().delete(tmpFolder.getId()).execute();

            logger.log(Level.INFO, "testTargetCanCreate: Can create target at " + settings.getPath());
            return true;
        } catch (Exception e) {
            logger.log(Level.INFO, "testTargetCanCreate: Can NOT create target", e);
            return false;
        }
    }

    @Override
    public boolean testRepoFileExists() {
        try {
            SyncanyRemoteFile remoteFile = new SyncanyRemoteFile();
            java.util.List<com.google.api.services.drive.model.File> curFiles = getRemoteFiles(remoteFile);

            if (curFiles.isEmpty()) {
                logger.log(Level.INFO, "testRepoFileExists: Repo file DOES NOT exist.");
                return false;
            } else if (curFiles.size() == 1) {
                logger.log(Level.INFO, "testRepoFileExists: Repo file exists.");
                return true;
            } else {
                throw new StorageException("testRepoFileExists: Multiple Repo files exist.");
            }
        } catch (Exception e) {
            logger.log(Level.INFO, "testRepoFileExists: Exception when trying to check repo file existence.", e);
            return false;
        }
    }
}