manager/qubesmanager/restore.py

#!/usr/bin/python2
#
# The Qubes OS Project, http://www.qubes-os.org
#
# Copyright (C) 2012  Agnieszka Kostrzewa <agnieszka.kostrzewa@gmail.com>
# Copyright (C) 2012  Marek Marczykowski <marmarek@mimuw.edu.pl>
#
# 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 2
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
#

import sys
import os
import shutil
from PyQt4.QtCore import *
from PyQt4.QtGui import *

from qubes.qubes import QubesVmCollection
from qubes.qubes import QubesException
from qubes.qubes import QubesDaemonPidfile
from qubes.qubes import QubesHost
from qubes.qubes import qubes_base_dir
import qubesmanager.resources_rc
import signal

from pyinotify import WatchManager, Notifier, ThreadedNotifier, EventsCodes, ProcessEvent

import time
from operator import itemgetter
from .thread_monitor import *

from qubes import backup
from qubes import qubesutils

from .ui_restoredlg import *
from .multiselectwidget import *

from .backup_utils import *
from multiprocessing import Queue, Event
from multiprocessing.queues import Empty

class RestoreVMsWindow(Ui_Restore, QWizard):

    __pyqtSignals__ = ("restore_progress(int)","backup_progress(int)")

    def __init__(self, app, qvm_collection, blk_manager, parent=None):
        super(RestoreVMsWindow, self).__init__(parent)

        self.app = app
        self.qvm_collection = qvm_collection
        self.blk_manager = blk_manager

        self.restore_options = None
        self.vms_to_restore = None
        self.func_output = []
        self.feedback_queue = Queue()
        self.canceled = False
        self.tmpdir_to_remove = None
        self.error_detected = Event()

        self.excluded = {}

        self.vm = self.qvm_collection[0]

        assert self.vm != None

        self.setupUi(self)

        self.select_vms_widget = MultiSelectWidget(self)
        self.select_vms_layout.insertWidget(1, self.select_vms_widget)

        self.connect(self, SIGNAL("currentIdChanged(int)"), self.current_page_changed)
        self.connect(self, SIGNAL("restore_progress(QString)"), self.commit_text_edit.append)
        self.connect(self, SIGNAL("backup_progress(int)"), self.progress_bar.setValue)
        self.dir_line_edit.connect(self.dir_line_edit, SIGNAL("textChanged(QString)"), self.backup_location_changed)
        self.connect(self.verify_only, SIGNAL("stateChanged(int)"),
                     self.on_verify_only_toogled)

        self.select_dir_page.isComplete = self.has_selected_dir
        self.select_vms_page.isComplete = self.has_selected_vms
        self.confirm_page.isComplete = self.all_vms_good
        #FIXME
        #this causes to run isComplete() twice, I don't know why
        self.select_vms_page.connect(self.select_vms_widget, SIGNAL("selected_changed()"), SIGNAL("completeChanged()"))

        fill_appvms_list(self)
        self.__init_restore_options__()

    @pyqtSlot(name='on_select_path_button_clicked')
    def select_path_button_clicked(self):
        select_path_button_clicked(self, True)

    def on_ignore_missing_toggled(self, checked):
        self.restore_options['use-default-template'] = checked
        self.restore_options['use-default-netvm'] = checked

    def on_ignore_uname_mismatch_toggled(self, checked):
        self.restore_options['ignore-username-mismatch'] = checked

    def on_verify_only_toogled(self, checked):
        self.restore_options['verify-only'] = bool(checked)

    def cleanupPage(self, p_int):
        if self.page(p_int) is self.select_vms_page:
            self.vms_to_restore = None
        else:
            super(RestoreVMsWindow, self).cleanupPage(p_int)

    def __fill_vms_list__(self):
        if self.vms_to_restore is not None:
            return

        self.select_vms_widget.selected_list.clear()
        self.select_vms_widget.available_list.clear()

        self.target_appvm = None
        if self.appvm_combobox.currentIndex() != 0:   #An existing appvm chosen
            self.target_appvm = self.qvm_collection.get_vm_by_name(
                    str(self.appvm_combobox.currentText()))

        try:
            self.vms_to_restore = backup.backup_restore_prepare(
                    self.dir_line_edit.text(),
                    self.passphrase_line_edit.text(),
                    options=self.restore_options,
                    host_collection=self.qvm_collection,
                    encrypted=self.encryption_checkbox.isChecked(),
                    appvm=self.target_appvm)

            for vmname in self.vms_to_restore:
                if vmname.startswith('$'):
                    # Internal info
                    continue
                self.select_vms_widget.available_list.addItem(vmname)
        except QubesException as ex:
            QMessageBox.warning (None, self.tr("Restore error!"), str(ex))

    def __init_restore_options__(self):
        if not self.restore_options:
            self.restore_options = {}
            backup.backup_restore_set_defaults(self.restore_options)

        if 'use-default-template' in self.restore_options and 'use-default-netvm' in self.restore_options:
            val = self.restore_options['use-default-template'] and self.restore_options['use-default-netvm']
            self.ignore_missing.setChecked(val)
        else:
            self.ignore_missing.setChecked(False)

        if 'ignore-username-mismatch' in self.restore_options:
            self.ignore_uname_mismatch.setChecked(self.restore_options['ignore-username-mismatch'])

    def gather_output(self, s):
        self.func_output.append(s)

    def restore_error_output(self, s):
        self.error_detected.set()
        self.feedback_queue.put((SIGNAL("restore_progress(QString)"),
                                 u'<font color="red">{0}</font>'.format(s)))

    def restore_output(self, s):
        self.feedback_queue.put((SIGNAL("restore_progress(QString)"),
                                 u'<font color="black">{0}</font>'.format(s)))

    def update_progress_bar(self, value):
        self.feedback_queue.put((SIGNAL("backup_progress(int)"), value))

    def __do_restore__(self, thread_monitor):
        err_msg = []
        self.qvm_collection.lock_db_for_writing()
        try:
            backup.backup_restore_do(self.vms_to_restore,
                                     self.qvm_collection,
                                     print_callback=self.restore_output,
                                     error_callback=self.restore_error_output,
                                     progress_callback=self.update_progress_bar)
        except backup.BackupCanceledError as ex:
            self.canceled = True
            self.tmpdir_to_remove = ex.tmpdir
            err_msg.append(str(ex))
        except Exception as ex:
            print ("Exception:", ex)
            err_msg.append(str(ex))
            err_msg.append(
                self.tr("Partially restored files left in "
                   "/var/tmp/restore_*, investigate them and/or clean them up"))

        self.qvm_collection.unlock_db()
        if self.canceled:
            self.emit(SIGNAL("restore_progress(QString)"),
                      '<b><font color="red">{0}</font></b>'
                      .format(self.tr("Restore aborted!")))
        elif len(err_msg) > 0 or self.error_detected.is_set():
            if len(err_msg) > 0:
                thread_monitor.set_error_msg('\n'.join(err_msg))
            self.emit(SIGNAL("restore_progress(QString)"),
                      '<b><font color="red">{0}</font></b>'
                      .format(self.tr("Finished with errors!")))
        else:
            self.emit(SIGNAL("restore_progress(QString)"),
                      '<font color="green">{0}</font>'
                      .format(self.tr("Finished successfully!")))

        thread_monitor.set_finished()

    def current_page_changed(self, id):

        old_sigchld_handler = signal.signal(signal.SIGCHLD, signal.SIG_DFL)
        if self.currentPage() is self.select_vms_page:
            self.__fill_vms_list__()

        elif self.currentPage() is self.confirm_page:
            for v in self.excluded:
                self.vms_to_restore[v] = self.excluded[v]
            self.excluded = {}
            for i in range(self.select_vms_widget.available_list.count()):
                vmname =  self.select_vms_widget.available_list.item(i).text()
                self.excluded[str(vmname)] = self.vms_to_restore[str(vmname)]
                del self.vms_to_restore[str(vmname)]

            del self.func_output[:]
            self.vms_to_restore = backup.restore_info_verify(self.vms_to_restore,
                                                             self.qvm_collection)
            backup.backup_restore_print_summary(
                    self.vms_to_restore, print_callback = self.gather_output)
            self.confirm_text_edit.setReadOnly(True)
            self.confirm_text_edit.setFontFamily("Monospace")
            self.confirm_text_edit.setText("\n".join(self.func_output))

            self.confirm_page.emit(SIGNAL("completeChanged()"))

        elif self.currentPage() is self.commit_page:
            self.button(self.FinishButton).setDisabled(True)
            self.showFileDialog.setEnabled(True)
            self.showFileDialog.setChecked(self.showFileDialog.isEnabled()
                                           and str(self.dir_line_edit.text())
                                           .count("media/") > 0)

            self.thread_monitor = ThreadMonitor()
            thread = threading.Thread (target= self.__do_restore__ , args=(self.thread_monitor,))
            thread.daemon = True
            thread.start()

            while not self.thread_monitor.is_finished():
                self.app.processEvents()
                time.sleep (0.1)
                try:
                    for (signal_to_emit,data) in iter(self.feedback_queue.get_nowait,None):
                        self.emit(signal_to_emit,data)
                except Empty:
                    pass

            if not self.thread_monitor.success:
                if self.canceled:
                    if self.tmpdir_to_remove and \
                        QMessageBox.warning(None, self.tr("Restore aborted"),
                            self.tr("Do you want to remove temporary files "
                                    "from %s?") % self.tmpdir_to_remove,
                            QMessageBox.Yes, QMessageBox.No) == \
                            QMessageBox.Yes:
                        shutil.rmtree(self.tmpdir_to_remove)
                else:
                    QMessageBox.warning(None,
                        self.tr("Backup error!"), self.tr("ERROR: {0}")
                                      .format(self.thread_monitor.error_msg))

            if self.showFileDialog.isChecked():
                self.emit(SIGNAL("restore_progress(QString)"),
                          '<b><font color="black">{0}</font></b>'.format(
                              self.tr(
                                  "Please unmount your backup volume and cancel"
                                  " the file selection dialog.")))
                if self.target_appvm:
                    self.target_appvm.run("QUBESRPC %s dom0" %
                                          "qubes.SelectDirectory")
                else:
                    file_dialog = QFileDialog()
                    file_dialog.setReadOnly(True)
                    file_dialog.getExistingDirectory(
                        self, self.tr("Detach backup device"),
                        os.path.dirname(self.dir_line_edit.text()))
            self.progress_bar.setValue(100)
            self.button(self.FinishButton).setEnabled(True)
            self.button(self.CancelButton).setEnabled(False)
            self.showFileDialog.setEnabled(False)

        signal.signal(signal.SIGCHLD, old_sigchld_handler)

    def all_vms_good(self):
        for vminfo in self.vms_to_restore.values():
            if not vminfo.has_key('vm'):
                continue
            if not vminfo['good-to-go']:
                return False
        return True

    def reject(self):
        if self.currentPage() is self.commit_page:
            if backup.backup_cancel():
                self.emit(SIGNAL("restore_progress(QString)"),
                          '<font color="red">{0}</font>'
                          .format(self.tr("Aborting the operation...")))
                self.button(self.CancelButton).setDisabled(True)
        else:
            self.done(0)

    def has_selected_dir(self):
        backup_location = self.dir_line_edit.text()
        if not backup_location:
            return False
        if self.appvm_combobox.currentIndex() == 0:
            if os.path.isfile(backup_location) or \
                    os.path.isfile(os.path.join(backup_location, 'qubes.xml')):
                return True
        else:
            return True

        return False

    def has_selected_vms(self):
        return self.select_vms_widget.selected_list.count() > 0

    def backup_location_changed(self, new_dir = None):
        self.select_dir_page.emit(SIGNAL("completeChanged()"))


# Bases on the original code by:
# Copyright (c) 2002-2007 Pascal Varet <p.varet@gmail.com>

def handle_exception( exc_type, exc_value, exc_traceback ):
    import sys
    import os.path
    import traceback

    filename, line, dummy, dummy = traceback.extract_tb( exc_traceback ).pop()
    filename = os.path.basename( filename )
    error    = "%s: %s" % ( exc_type.__name__, exc_value )

    QMessageBox.critical(None, "Houston, we have a problem...",
                         "Whoops. A critical error has occured. This is most likely a bug "
                         "in Qubes Restore VMs application.<br><br>"
                         "<b><i>%s</i></b>" % error +
                         "at <b>line %d</b> of file <b>%s</b>.<br/><br/>"
                         % ( line, filename ))




def main():

    global qubes_host
    qubes_host = QubesHost()

    global app
    app = QApplication(sys.argv)
    app.setOrganizationName("The Qubes Project")
    app.setOrganizationDomain("http://qubes-os.org")
    app.setApplicationName("Qubes Restore VMs")

    sys.excepthook = handle_exception

    qvm_collection = QubesVmCollection()
    qvm_collection.lock_db_for_reading()
    qvm_collection.load()
    qvm_collection.unlock_db()

    global restore_window
    restore_window = RestoreVMsWindow()

    restore_window.show()

    app.exec_()
    app.exit()



if __name__ == "__main__":
    main()