feat!: Remove "fuse" user group handling and checking

The following behavior, introduced in 2013 via 26474f8, was removed: While installing (in configure script) and when mounting (see mount.py::MountControl.checkFuse()) the existence of the user group "fuse" was checked. The reasons and arguments described in #1450.

BREAKING CHANGE: Behavior shouldn't change. The behavior should not have changed. However, there could be edge cases.

Close #1450

common/configure

@@ -12,23 +12,17 @@ UNINSTALL_DIRS="$(mktemp)"
 
 #set default options
 PYTHON="--python3"
-FUSE_GROUP="--no-fuse-group"
 
 USR_BIN_FILES="backintime backintime-askpass"
-FUSE_FILES="mount.py"
 
 usage () {
  echo "Usage:"
- echo "$0 [--python | --python3], [--fuse-group | --no-fuse-group]"
+ echo "$0 [--python | --python3]"
  echo ""
  echo "--python"
  echo "\tuse 'python' to start Python3"
  echo "--python3"
  echo "\tuse 'python3' to start Python3"
- echo "--no-fuse-group"
- echo "\tdo not check for 'fuse' group membership (if not necessary on destination platform)"
- echo "--fuse-group"
- echo "\tmake sure user is in the group 'fuse' to be able to use fuse-based file-systems"
 }
 
 addInstallFiles () {
@@ -120,7 +114,6 @@ unknown_args=""
 for arg in $*; do
  case $arg in
  --python | --python3) PYTHON=$arg;;
- --fuse-group | --no-fuse-group) FUSE_GROUP=$arg;;
  --help | -h) usage; exit 0;;
  *) unknown_args="$unknown_args $arg";;
  esac
@@ -140,15 +133,6 @@ sed -e "s/^python3\? /python${PYVERSION} /g" \
  -e "s/^ssh-agent python3\? /ssh-agent python${PYVERSION} /g" \
  -i $USR_BIN_FILES
 
-#patch check for 'fuse' group
-#Some distributions require user to be in group 'fuse' to use sshfs and encfs
-case $FUSE_GROUP in
- --fuse-group) CHECKFUSE="True" ;;
- --no-fuse-group) CHECKFUSE="False";;
-esac
-sed -e "s/CHECK_FUSE_GROUP = \(True\|False\)/CHECK_FUSE_GROUP = ${CHECKFUSE}/" \
- -i $FUSE_FILES
-
 #check languages
 mos=""
 langs=""

common/mount.py

@@ -420,8 +420,6 @@ class MountControl(object):
  mountpoints
  """
 
- CHECK_FUSE_GROUP = False
-
  def __init__(self,
  cfg = None,
  profile_id = None,
@@ -592,7 +590,7 @@ def _umount(self):
  overwritten by backends which subclasses :py:class:`MountControl`.
 
  Raises:
- exceptions.MountException:  if unmount failed
+ exceptions.MountException: If unmount failed.
  """
  try:
  subprocess.check_call(['fusermount', '-u', self.currentMountpoint])
@@ -675,42 +673,21 @@ def postUmountCheck(self):
 
  def checkFuse(self):
  """
- Check if command in self.mountproc is installed and user is part of
- group ``fuse``.
+ Check if command in ``self.mountproc`` is installed.
 
  Raises:
- exceptions.MountException: if either command is not available or
- user is not in group fuse
+ exceptions.MountException: If either command is not available.
  """
- logger.debug('Check fuse', self)
 
  if not tools.checkCommand(self.mountproc):
  logger.debug('%s is missing' % self.mountproc, self)
+
  raise MountException(
- '{}  not found. Please install e.g. {}'
+ '{} not found. Please install e.g. {}'
  .format(self.mountproc,
  "'apt-get install %s'" % self.mountproc)
  )
 
- if self.CHECK_FUSE_GROUP:
- user = self.config.user()
-
- try:
- fuse_grp_members = grp.getgrnam('fuse')[3]
-
- except KeyError:
- #group fuse doesn't exist. So most likely it isn't used by this distribution
- logger.debug("Group fuse doesn't exist. Skip test", self)
- return
-
- if not user in fuse_grp_members:
- logger.debug('User %s is not in group fuse' % user, self)
- raise MountException(
- "{user} is not member of group 'fuse'. Run 'sudo adduser "
- "{user} fuse'. To apply changes logout and login again."
- "\nLook at 'man backintime' for further instructions."
- .format(user=user))
-
  def mounted(self):
  """
  Check if the mountpoint is already mounted.

common/sshtools.py

@@ -197,9 +197,11 @@ def _mount(self):
 
  err = proc.communicate()[1]
 
- if proc.returncode:
- raise MountException(
- "Can't mount %s" % " ".join(sshfs) + "\n\n" + err)
+ if proc.returncode == 0:
+ return
+
+ raise MountException("Can't mount {}\n\n{}"
+ .format(" ".join(sshfs), err))
 
  def preMountCheck(self, first_run=False):
  """

qt/settingsdialog.py

@@ -20,7 +20,6 @@
 import os
 import datetime
 import copy
-import grp
 import re
 
 from PyQt5.QtGui import QIcon, QFont, QPalette, QBrush, QColor
@@ -2106,32 +2105,17 @@ def __init__(self, parent):
  snapshots.SID(datetime.datetime.now(), self.config).sid
  )
 
- # inform user to join group fuse if he hasn't already.
- # If there is no group fuse than it is most likely not necessary.
- addFuse = ''
-
- try:
- user = self.config.user()
- fuse_grp_members = grp.getgrnam('fuse')[3]
-
- if user not in fuse_grp_members:
- addFuse = _(' and add your user to group \'fuse\'')
-
- except KeyError:
- pass
-
  label = QLabel(_(
  "Please navigate to the snapshot from which you want to restore "
  "{appName}'s configuration. The path may look like:\n"
  "{samplePath}\n\nIf your snapshots are on a remote drive or if "
  "they are encrypted you need to manually mount them first. "
  "If you use Mode SSH you also may need to set up public key "
- "login to the remote host{addFuse}.\n"
+ "login to the remote host.\n"
  "Take a look at 'man backintime'.")
  .format(
  appName=self.config.APP_NAME,
- samplePath=samplePath,
- addFuse=addFuse),
+ samplePath=samplePath),
  self
  )
  label.setWordWrap(True)