def _recover_checkpoint(self, cp_dir):
"""Recover a specific checkpoint.
Recover a specific checkpoint provided by cp_dir
Note: this function does not reload augeas.
:param str cp_dir: checkpoint directory file path
:raises errors.ReverterError: If unable to recover checkpoint
"""
if os.path.isfile(os.path.join(cp_dir, "FILEPATHS")):
try:
with open(os.path.join(cp_dir, "FILEPATHS")) as paths_fd:
filepaths = paths_fd.read().splitlines()
for idx, path in enumerate(filepaths):
shutil.copy2(
os.path.join(
cp_dir,
os.path.basename(path) + "_" + str(idx)), path)
except (IOError, OSError):
# This file is required in all checkpoints.
logger.error("Unable to recover files from %s", cp_dir)
raise errors.ReverterError("Unable to recover files from %s" %
cp_dir)
# Remove any newly added files if they exist
self._remove_contained_files(os.path.join(cp_dir, "NEW_FILES"))
try:
shutil.rmtree(cp_dir)
except OSError:
logger.error("Unable to remove directory: %s", cp_dir)
raise errors.ReverterError("Unable to remove directory: %s" %
cp_dir)
def _check_tempfile_saves(self, save_files):
"""Verify save isn't overwriting any temporary files.
:param set save_files: Set of files about to be saved.
:raises letsencrypt.errors.ReverterError:
when save is attempting to overwrite a temporary file.
"""
protected_files = []
# Get temp modified files
temp_path = os.path.join(self.config.temp_checkpoint_dir, "FILEPATHS")
if os.path.isfile(temp_path):
with open(temp_path, "r") as protected_fd:
protected_files.extend(protected_fd.read().splitlines())
# Get temp new files
new_path = os.path.join(self.config.temp_checkpoint_dir, "NEW_FILES")
if os.path.isfile(new_path):
with open(new_path, "r") as protected_fd:
protected_files.extend(protected_fd.read().splitlines())
# Verify no save_file is in protected_files
for filename in protected_files:
if filename in save_files:
raise errors.ReverterError("Attempting to overwrite challenge "
"file - %s" % filename)
def register_undo_command(self, temporary, command):
"""Register a command to be run to undo actions taken.
.. warning:: This function does not enforce order of operations in terms
of file modification vs. command registration. All undo commands
are run first before all normal files are reverted to their previous
state. If you need to maintain strict order, you may create
checkpoints before and after the the command registration. This
function may be improved in the future based on demand.
:param bool temporary: Whether the command should be saved in the
IN_PROGRESS or TEMPORARY checkpoints.
:param command: Command to be run.
:type command: list of str
"""
commands_fp = os.path.join(self._get_cp_dir(temporary), "COMMANDS")
command_file = None
try:
if os.path.isfile(commands_fp):
command_file = open(commands_fp, "ab")
else:
command_file = open(commands_fp, "wb")
csvwriter = csv.writer(command_file)
csvwriter.writerow(command)
except (IOError, OSError):
logger.error("Unable to register undo command")
raise errors.ReverterError("Unable to register undo command.")
finally:
if command_file is not None:
command_file.close()
def recovery_routine(self):
"""Revert configuration to most recent finalized checkpoint.
Remove all changes (temporary and permanent) that have not been
finalized. This is useful to protect against crashes and other
execution interruptions.
:raises .errors.ReverterError: If unable to recover the configuration
"""
# First, any changes found in IConfig.temp_checkpoint_dir are removed,
# then IN_PROGRESS changes are removed The order is important.
# IN_PROGRESS is unable to add files that are already added by a TEMP
# change. Thus TEMP must be rolled back first because that will be the
# 'latest' occurrence of the file.
self.revert_temporary_config()
if os.path.isdir(self.config.in_progress_dir):
try:
self._recover_checkpoint(self.config.in_progress_dir)
except errors.ReverterError:
# We have a partial or incomplete recovery
logger.fatal(
"Incomplete or failed recovery for IN_PROGRESS "
"checkpoint - %s", self.config.in_progress_dir)
raise errors.ReverterError(
"Incomplete or failed recovery for IN_PROGRESS checkpoint "
"- %s" % self.config.in_progress_dir)
def register_file_creation(self, temporary, *files):
r"""Register the creation of all files during letsencrypt execution.
Call this method before writing to the file to make sure that the
file will be cleaned up if the program exits unexpectedly.
(Before a save occurs)
:param bool temporary: If the file creation registry is for
a temp or permanent save.
:param \*files: file paths (str) to be registered
:raises letsencrypt.errors.ReverterError: If
call does not contain necessary parameters or if the file creation
is unable to be registered.
"""
# Make sure some files are provided... as this is an error
# Made this mistake in my initial implementation of apache.dvsni.py
if not files:
raise errors.ReverterError(
"Forgot to provide files to registration call")
if temporary:
cp_dir = self.config.temp_checkpoint_dir
else:
cp_dir = self.config.in_progress_dir
le_util.make_or_verify_dir(cp_dir, constants.CONFIG_DIRS_MODE,
os.geteuid())
# Append all new files (that aren't already registered)
new_fd = None
try:
new_fd, ex_files = self._read_and_append(
os.path.join(cp_dir, "NEW_FILES"))
for path in files:
if path not in ex_files:
new_fd.write("{0}{1}".format(path, os.linesep))
except (IOError, OSError):
logger.error("Unable to register file creation(s) - %s", files)
raise errors.ReverterError(
"Unable to register file creation(s) - {0}".format(files))
finally:
if new_fd is not None:
new_fd.close()
def test_recover_checkpoint_rollback_failure(self):
mock_recover = mock.MagicMock(side_effect=errors.ReverterError("e"))
# pylint: disable=protected-access
self.reverter._recover_checkpoint = mock_recover
self.reverter.add_to_checkpoint(self.sets[0], "config1 save")
self.reverter.finalize_checkpoint("Title")
self.assertRaises(errors.ReverterError,
self.reverter.rollback_checkpoints, 1)
def view_config_changes(self, for_logging=False, num=None):
"""Displays all saved checkpoints.
All checkpoints are printed by
:meth:`letsencrypt.interfaces.IDisplay.notification`.
.. todo:: Decide on a policy for error handling, OSError IOError...
:raises .errors.ReverterError: If invalid directory structure.
"""
backups = os.listdir(self.config.backup_dir)
backups.sort(reverse=True)
if num:
backups = backups[:num]
if not backups:
logger.info("The Let's Encrypt client has not saved any backups "
"of your configuration")
return
# Make sure there isn't anything unexpected in the backup folder
# There should only be timestamped (float) directories
try:
for bkup in backups:
float(bkup)
except ValueError:
raise errors.ReverterError("Invalid directories in {0}".format(
self.config.backup_dir))
output = []
for bkup in backups:
output.append(time.ctime(float(bkup)))
cur_dir = os.path.join(self.config.backup_dir, bkup)
with open(os.path.join(cur_dir, "CHANGES_SINCE")) as changes_fd:
output.append(changes_fd.read())
output.append("Affected files:")
with open(os.path.join(cur_dir, "FILEPATHS")) as paths_fd:
filepaths = paths_fd.read().splitlines()
for path in filepaths:
output.append(" {0}".format(path))
if os.path.isfile(os.path.join(cur_dir, "NEW_FILES")):
with open(os.path.join(cur_dir, "NEW_FILES")) as new_fd:
output.append("New Configuration Files:")
filepaths = new_fd.read().splitlines()
for path in filepaths:
output.append(" {0}".format(path))
output.append(os.linesep)
if for_logging:
return os.linesep.join(output)
zope.component.getUtility(interfaces.IDisplay).notification(
os.linesep.join(output), display_util.HEIGHT)
def test_recover_checkpoint_revert_temp_failures(self):
mock_recover = mock.MagicMock(side_effect=errors.ReverterError("e"))
# pylint: disable=protected-access
self.reverter._recover_checkpoint = mock_recover
self.reverter.add_to_temp_checkpoint(self.sets[0], "config1 save")
self.assertRaises(errors.ReverterError,
self.reverter.revert_temporary_config)
def rollback_checkpoints(self, rollback=1):
"""Revert 'rollback' number of configuration checkpoints.
:param int rollback: Number of checkpoints to reverse. A str num will be
cast to an integer. So "2" is also acceptable.
:raises .ReverterError:
if there is a problem with the input or if the function is
unable to correctly revert the configuration checkpoints
"""
try:
rollback = int(rollback)
except ValueError:
logger.error("Rollback argument must be a positive integer")
raise errors.ReverterError("Invalid Input")
# Sanity check input
if rollback < 0:
logger.error("Rollback argument must be a positive integer")
raise errors.ReverterError("Invalid Input")
backups = os.listdir(self.config.backup_dir)
backups.sort()
if not backups:
logger.warning(
"Let's Encrypt hasn't modified your configuration, so rollback "
"isn't available.")
elif len(backups) < rollback:
logger.warning("Unable to rollback %d checkpoints, only %d exist",
rollback, len(backups))
while rollback > 0 and backups:
cp_dir = os.path.join(self.config.backup_dir, backups.pop())
try:
self._recover_checkpoint(cp_dir)
except errors.ReverterError:
logger.fatal("Failed to load checkpoint during rollback")
raise errors.ReverterError(
"Unable to load checkpoint during rollback")
rollback -= 1
def _add_to_checkpoint_dir(self, cp_dir, save_files, save_notes):
"""Add save files to checkpoint directory.
:param str cp_dir: Checkpoint directory filepath
:param set save_files: set of files to save
:param str save_notes: notes about changes made during the save
:raises IOError: if unable to open cp_dir + FILEPATHS file
:raises .ReverterError: if unable to add checkpoint
"""
le_util.make_or_verify_dir(cp_dir, constants.CONFIG_DIRS_MODE,
os.geteuid(),
self.config.strict_permissions)
op_fd, existing_filepaths = self._read_and_append(
os.path.join(cp_dir, "FILEPATHS"))
idx = len(existing_filepaths)
for filename in save_files:
# No need to copy/index already existing files
# The oldest copy already exists in the directory...
if filename not in existing_filepaths:
# Tag files with index so multiple files can
# have the same filename
logger.debug("Creating backup of %s", filename)
try:
shutil.copy2(
filename,
os.path.join(
cp_dir,
os.path.basename(filename) + "_" + str(idx)))
op_fd.write(filename + os.linesep)
# http://stackoverflow.com/questions/4726260/effective-use-of-python-shutil-copy2
except IOError:
op_fd.close()
logger.error("Unable to add file %s to checkpoint %s",
filename, cp_dir)
raise errors.ReverterError(
"Unable to add file {0} to checkpoint "
"{1}".format(filename, cp_dir))
idx += 1
op_fd.close()
with open(os.path.join(cp_dir, "CHANGES_SINCE"), "a") as notes_fd:
notes_fd.write(save_notes)
def revert_temporary_config(self):
"""Reload users original configuration files after a temporary save.
This function should reinstall the users original configuration files
for all saves with temporary=True
:raises .ReverterError: when unable to revert config
"""
if os.path.isdir(self.config.temp_checkpoint_dir):
try:
self._recover_checkpoint(self.config.temp_checkpoint_dir)
except errors.ReverterError:
# We have a partial or incomplete recovery
logger.fatal("Incomplete or failed recovery for %s",
self.config.temp_checkpoint_dir)
raise errors.ReverterError("Unable to revert temporary config")
def finalize_checkpoint(self, title):
"""Finalize the checkpoint.
Timestamps and permanently saves all changes made through the use
of :func:`~add_to_checkpoint` and :func:`~register_file_creation`
:param str title: Title describing checkpoint
:raises letsencrypt.errors.ReverterError: when the
checkpoint is not able to be finalized.
"""
# Check to make sure an "in progress" directory exists
if not os.path.isdir(self.config.in_progress_dir):
return
changes_since_path = os.path.join(self.config.in_progress_dir,
"CHANGES_SINCE")
changes_since_tmp_path = os.path.join(self.config.in_progress_dir,
"CHANGES_SINCE.tmp")
if not os.path.exists(changes_since_path):
logger.info("Rollback checkpoint is empty (no changes made?)")
with open(self.config.changes_since_path) as f:
f.write("No changes\n")
# Add title to self.config.in_progress_dir CHANGES_SINCE
try:
with open(changes_since_tmp_path, "w") as changes_tmp:
changes_tmp.write("-- %s --\n" % title)
with open(changes_since_path, "r") as changes_orig:
changes_tmp.write(changes_orig.read())
# Move self.config.in_progress_dir to Backups directory
shutil.move(changes_since_tmp_path, changes_since_path)
except (IOError, OSError):
logger.error("Unable to finalize checkpoint - adding title")
logger.debug("Exception was:\n%s", traceback.format_exc())
raise errors.ReverterError("Unable to add title")
# rename the directory as a timestamp
self._timestamp_progress_dir()
def _timestamp_progress_dir(self):
"""Timestamp the checkpoint."""
# It is possible save checkpoints faster than 1 per second resulting in
# collisions in the naming convention.
for _ in xrange(2):
timestamp = self._checkpoint_timestamp()
final_dir = os.path.join(self.config.backup_dir, timestamp)
try:
os.rename(self.config.in_progress_dir, final_dir)
return
except OSError:
logger.warning(
"Extreme, unexpected race condition, retrying (%s)",
timestamp)
# After 10 attempts... something is probably wrong here...
logger.error("Unable to finalize checkpoint, %s -> %s",
self.config.in_progress_dir, final_dir)
raise errors.ReverterError("Unable to finalize checkpoint renaming")
def _timestamp_progress_dir(self):
"""Timestamp the checkpoint."""
# It is possible save checkpoints faster than 1 per second resulting in
# collisions in the naming convention.
cur_time = time.time()
for _ in xrange(10):
final_dir = os.path.join(self.config.backup_dir, str(cur_time))
try:
os.rename(self.config.in_progress_dir, final_dir)
return
except OSError:
# It is possible if the checkpoints are made extremely quickly
# that will result in a name collision.
# If so, increment and try again
cur_time += .01
# After 10 attempts... something is probably wrong here...
logger.error("Unable to finalize checkpoint, %s -> %s",
self.config.in_progress_dir, final_dir)
raise errors.ReverterError("Unable to finalize checkpoint renaming")
def _remove_contained_files(self, file_list): # pylint: disable=no-self-use
"""Erase all files contained within file_list.
:param str file_list: file containing list of file paths to be deleted
:returns: Success
:rtype: bool
:raises letsencrypt.errors.ReverterError: If
all files within file_list cannot be removed
"""
# Check to see that file exists to differentiate can't find file_list
# and can't remove filepaths within file_list errors.
if not os.path.isfile(file_list):
return False
try:
with open(file_list, "r") as list_fd:
filepaths = list_fd.read().splitlines()
for path in filepaths:
# Files are registered before they are added... so
# check to see if file exists first
if os.path.lexists(path):
os.remove(path)
else:
logger.warning(
"File: %s - Could not be found to be deleted %s - "
"LE probably shut down unexpectedly", os.linesep,
path)
except (IOError, OSError):
logger.fatal("Unable to remove filepaths contained within %s",
file_list)
raise errors.ReverterError(
"Unable to remove filepaths contained within "
"{0}".format(file_list))
return True
def test_recovery_routine_throws_error_from_reverter(self, mock_recovery_routine):
mock_recovery_routine.side_effect = errors.ReverterError("foo")
self.assertRaises(errors.PluginError, self.config.recovery_routine)
def test_view_config_changes_throws_error_from_reverter(self, mock_view_config_changes):
mock_view_config_changes.side_effect = errors.ReverterError("foo")
self.assertRaises(errors.PluginError, self.config.view_config_changes)
def test_rollback_checkpoints_throws_error_from_reverter(self, mock_rollback_checkpoints):
mock_rollback_checkpoints.side_effect = errors.ReverterError("foo")
self.assertRaises(errors.PluginError, self.config.rollback_checkpoints)
def test_revert_challenge_config_throws_error_from_reverter(self, mock_revert_temporary_config):
mock_revert_temporary_config.side_effect = errors.ReverterError("foo")
self.assertRaises(errors.PluginError, self.config.revert_challenge_config)
def test_save_throws_error_from_reverter(self, mock_add_to_checkpoint):
mock_add_to_checkpoint.side_effect = errors.ReverterError("foo")
self.assertRaises(errors.PluginError, self.config.save)