class DeleteRemoteProcess(AppOneShotProcess):
def __init__(self, remote_address: str, remote_username: str,
remote_port: int, remote_path: str, file_name: str):
super().__init__(name=self.__class__.__name__)
self.__remote_path = remote_path
self.__file_name = file_name
self.__ssh = Ssh(host=remote_address,
port=remote_port,
user=remote_username)
def run_once(self):
self.__ssh.set_base_logger(self.logger)
file_path = os.path.join(self.__remote_path, self.__file_name)
self.logger.debug("Deleting remote file {}".format(self.__file_name))
try:
out = self.__ssh.run_command("rm -rf '{}'".format(file_path))
self.logger.debug("Remote delete output: {}".format(out.decode()))
except SshError:
self.logger.exception("Exception while deleting remote file")
class RemoteScanner(IScanner):
"""
Scanner implementation to scan the remote filesystem
"""
RETRY_COUNT = 5
def __init__(self, remote_address: str, remote_username: str,
remote_port: int, remote_path_to_scan: str,
local_path_to_scan_script: str,
remote_path_to_scan_script: str):
self.logger = logging.getLogger("RemoteScanner")
self.__remote_path_to_scan = remote_path_to_scan
self.__local_path_to_scan_script = local_path_to_scan_script
self.__remote_path_to_scan_script = remote_path_to_scan_script
self.__ssh = Ssh(host=remote_address,
port=remote_port,
user=remote_username)
self.__scp = Scp(host=remote_address,
port=remote_port,
user=remote_username)
self.__first_run = True
@overrides(IScanner)
def set_base_logger(self, base_logger: logging.Logger):
self.logger = base_logger.getChild("RemoteScanner")
self.__ssh.set_base_logger(self.logger)
self.__scp.set_base_logger(self.logger)
@overrides(IScanner)
def scan(self) -> List[SystemFile]:
if self.__first_run:
self._install_scanfs()
self.__first_run = False
retries = 0
out = None
while out is None:
try:
out = self.__ssh.run_command("{} {}".format(
self.__remote_path_to_scan_script,
self.__remote_path_to_scan))
except SshError as e:
# Suppress specific errors and retry a fixed number of times
# Otherwise raise a fatal AppError
if RemoteScanner.__suppress_error(
e) and retries < RemoteScanner.RETRY_COUNT:
self.logger.warning(
"Retrying remote scan after error: {}".format(str(e)))
out = None
retries += 1
else:
self.logger.exception("Caught an SshError")
raise AppError(Localization.Error.REMOTE_SERVER_SCAN)
remote_files = pickle.loads(out)
return remote_files
def _install_scanfs(self):
self.logger.info("Installing local:{} to remote:{}".format(
self.__local_path_to_scan_script,
self.__remote_path_to_scan_script))
if not os.path.isfile(self.__local_path_to_scan_script):
raise RemoteScannerError(
"Failed to find scanfs executable at {}".format(
self.__local_path_to_scan_script))
try:
self.__scp.copy(local_path=self.__local_path_to_scan_script,
remote_path=self.__remote_path_to_scan_script)
except ScpError:
self.logger.exception("Caught scp exception")
raise AppError(Localization.Error.REMOTE_SERVER_INSTALL)
@staticmethod
def __suppress_error(error: SshError) -> bool:
return "text file busy" in str(error).lower()
