gdata-get.py

# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
#
# Copyright 2011 Carlos Abalde <carlos.abalde@gmail.com>
#
# This file was originally part of duplicity.
#
# Duplicity 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 2 of the License, or (at your
# option) any later version.
#
# Duplicity 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 duplicity; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

import os.path
import string
import urllib

class GDocsBackend():
    """Connect to remote store using Google Google Documents List API"""

    ROOT_FOLDER_ID = 'folder%3Aroot'
    BACKUP_DOCUMENT_TYPE = 'application/binary'

    def __init__(self):

        # Import Google Data APIs libraries.
        try:
            global atom
            global gdata
            import atom.data
            import gdata.client
            import gdata.docs.client
            import gdata.docs.data
        except ImportError:
            raise BackendException('Google Docs backend requires Google Data APIs Python '
                                   'Client Library (see http://code.google.com/p/gdata-python-client/).')

        # Setup client instance.
        self.client = gdata.docs.client.DocsClient(source='duplicity 0.7.01')
        self.client.ssl = True
        self.client.http_client.debug = False
        self._authorize('USERNAME' + '@' + 'DOMAIN', 'PASSWORD')

        # Fetch destination folder entry (and crete hierarchy if required).
        folder_names = [ 'test-gdata' ];
        parent_folder = None
        parent_folder_id = GDocsBackend.ROOT_FOLDER_ID
        for folder_name in folder_names:
            entries = self._fetch_entries(parent_folder_id, 'folder', folder_name)
            if entries is not None:
                if len(entries) == 1:
                    parent_folder = entries[0]
                elif len(entries) == 0:
                    folder = gdata.docs.data.Resource(type='folder', title=folder_name)
                    parent_folder = self.client.create_resource(folder, collection=parent_folder)
                else:
                    parent_folder = None
                if parent_folder:
                    parent_folder_id = parent_folder.resource_id.text
                else:
                    raise BackendException("Error while creating destination folder '%s'." % folder_name)
            else:
                raise BackendException("Error while fetching destination folder '%s'." % folder_name)
        self.folder = parent_folder

    def _get(self, remote_filename, local_path):
        entries = self._fetch_entries(self.folder.resource_id.text,
                                      GDocsBackend.BACKUP_DOCUMENT_TYPE,
                                      remote_filename)
        if len(entries) == 1:
            entry = entries[0]
            self.client.DownloadResource(entry, local_path) #.name)
        else:
            raise BackendException("Failed to find file '%s' in remote folder '%s'"
                                   % (remote_filename, self.folder.title.text))

    def _authorize(self, email, password, captcha_token=None, captcha_response=None):
        try:
            self.client.client_login(email,
                                     password,
                                     source='duplicity 0.7.01',
                                     service='writely',
                                     captcha_token=captcha_token,
                                     captcha_response=captcha_response)
        except gdata.client.CaptchaChallenge as challenge:
            print('A captcha challenge in required. Please visit ' + challenge.captcha_url)
            answer = None
            while not answer:
                answer = raw_input('Answer to the challenge? ')
            self._authorize(email, password, challenge.captcha_token, answer)
        except gdata.client.BadAuthentication:
            raise BackendException('Invalid user credentials given. Be aware that accounts '
                                   'that use 2-step verification require creating an application specific '
                                   'access code for using this Duplicity backend. Follow the instruction in '
                                   'http://www.google.com/support/accounts/bin/static.py?page=guide.cs&guide=1056283&topic=1056286 '
                                   'and create your application-specific password to run duplicity backups.')

    def _fetch_entries(self, folder_id, type, title=None):
        # Build URI.
        uri = '/feeds/default/private/full/%s/contents' % folder_id
        if type == 'folder':
            uri += '/-/folder?showfolders=true'
        elif type == GDocsBackend.BACKUP_DOCUMENT_TYPE:
            uri += '?showfolders=false'
        else:
            uri += '?showfolders=true'
        if title:
            uri += '&title=' + urllib.quote(title) + '&title-exact=true'

        # Fetch entries.
        entries = self.client.get_all_resources(uri=uri)

        # Done!
        return entries

g=GDocsBackend()

g._get('bigvid.avi', '/mnt/bigstore/tmp/testbigdownload.avi')