def load(self, filename):
"""Load configuration file.
:param filename:
"""
# Protect against directory traversals.
filename = os_path.basename(filename)
# Absolute path to configuration file.
filepath = os_path.join(self.CONFIG_PATH, filename)
# FIXME: Use ``os_path.exists``.
try:
os.stat(filepath)
except OSError:
return
log.info('Reading configuration file {}'.format(filepath))
try:
with open(filepath, "r") as instream:
payload = instream.read()
data = json.loads(payload)
return data
except Exception as ex:
log.exc(ex, 'Reading configuration from "{}" failed'.format(filepath))
def backup_file(filename, backup_path, backup_count):
"""
Backup file using a rotation mechanism.
:param filename:
:param backup_path:
:param backup_count:
:return:
"""
# Sanity checks.
if not file_exists(filename):
log.info('File {} does not exist, skipping backup'.format(filename))
return
#log.info('Preparing backup')
# Running this here will crash the machine.
#ensure_directory(backup_path)
filepath = os_path.join(backup_path, os_path.basename(filename))
outfile = RotatingFile(filepath, backup_count)
log.info('Creating backup of {}'.format(filename))
with open(filename, "r") as f:
outfile.write(f)
def save(self, filename, instream):
"""
Save configuration file, with rotating backup.
"""
import uos
# Protect against directory traversals.
filename = os_path.basename(filename)
# Only allow specific filenames.
if 'settings' not in filename:
raise ValueError(
'Writing arbitrary files to the system is prohibited')
# Absolute path to configuration file.
filepath = os_path.join(self.CONFIG_PATH, filename)
# Number of backup files to keep around.
backup_count = self.get('main.backup.file_count', 7)
# Backup configuration file.
log.info(
'Backing up file {} to {}, keeping a history worth of {} files'.
format(filepath, self.BACKUP_PATH, backup_count))
backup_file(filepath, self.BACKUP_PATH, backup_count)
# Overwrite configuration file.
log.info('Saving configuration file {}'.format(filepath))
with open(filepath, "w") as outstream:
if isinstance(instream, str):
outstream.write(instream)
else:
copyfileobj(instream, outstream)
uos.sync()
