I've written a function to copy files remote-to-remote using SCP command, paramiko, pexpect, and paramiko-sftp.
I want to make my code efficient; I'm new to Python and I don't know how.
Here's my logic in 3 steps:
- Find checksum of a file by executing
cksumcommand in remote-1. - Executing SCP command from my local to copy file remote-1 to remote-2.
- Again do checksum and compare both to give status.
Here is my code:
class remote_file_operations():
"""
Class which supports remote file operations
"""
def __init__(self, host=None, username=None, password=None, port=22):
"""
*Method description :* Initialize and setup connection
:param host: Remote Host
:type host: str
:param username: Remote Host Username
:type username: str
:param password: Remote Host password
:type password: str
:param port: port to connect, default port is 22
:type port: int
"""
if host and username and password:
self.sftp = None
self.sftp_open = False
self.client = paramiko.client.SSHClient()
self.client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
try:
self.client.connect(host, port=port,
username=username, password=password, timeout=10)
except paramiko.ssh_exception.AuthenticationException:
sys.exit("[Authentication Error] Please check user: '%s' or password" % username)
except TimeoutError:
sys.exit("Connection Refused")
except socket.gaierror:
sys.exit("Host Name: '%s' not found" % host)
def _open_sftp_connection(self):
"""
*Method description :* Opens an SFTP connection if not already open
"""
if not self.sftp_open:
self.sftp = self.client.open_sftp()
self.sftp_open = True
return self.sftp_open
@staticmethod
def file_check_sum(user, host, password, file_paths):
"""
*Method description :* Give check sum value by cksum command in remote.
:param user: username :type user: str
:param host: hostname :type host: str
:param password: password :type password: str
:param file_paths: list of file paths :type file_paths: list
:return check_sum: dict with key as filename and value as checksum :type check_sum: dict
"""
status = True
logger.console("Finding checksum ...")
check_sum = dict()
rmt_ses = remote_file_operations(host, user, password)
for file_path in file_paths:
_, stdout, stderr = rmt_ses.client.exec_command("ls %s" % file_path.replace("\\", ""))
if b"No such file or directory" not in stderr.read():
for abs_file_path in stdout:
cmd = "cksum %s" % abs_file_path.replace("\n", "").replace("\r", "")
(_, stdout, stderr) = rmt_ses.client.exec_command(cmd)
sum_line = stdout.read().decode("utf-8").replace(abs_file_path, "")
file_name = abs_file_path.split("/")[-1]
check_sum[file_name] = sum_line.replace("\n", "").strip()
logger.console(check_sum)
else:
logger.error("File doesn't exist: %s:%s" % (host, file_path))
status = False
rmt_ses.client.close()
return status, check_sum
@staticmethod
def scp_remote_remote(host_1, user_1, password_1, host_2, user_2, password_2, src, dest):
#pylint: disable=too-many-arguments,try-except-raise,too-many-locals,too-many-branches
"""
*Method description :* SCP files from one remote to another remote
:param host_1: Remote host-1 :type host_1: str
:param user_1: Remote user-1 :type user_1: str
:param password_1: Remote Host-1 password :type password_1: str
:param host_2: Remote host-2 :type host_2: str
:param user_2: Remote user-2 :type user_2: str
:param password_2: Remote Host-2 password :type password_2: str
:param src: Source dir/file :type src: str
:param dest: Destination dir/file :type dest: str
:return output: Output generated while scp
:type output: list
"""
exp_pwd_2, status, output = None, False, list()
check, src_check_sum = remote_file_operations.file_check_sum(user_1, host_1, password_1, [src])
if check:
command = "scp -r %s@%s:%s %s@%s:%s" % (user_1, host_1, src, user_2, host_2, dest)
logger.console("Executing: %s" % command)
try:
child = pexpect.spawn(command, timeout=COPY_TIMEOUT)
logger.console("Please wait while copying files from %s to %s ..." % (host_1, host_2))
exp_pwd_1 = child.expect(["password:", "want to continue connecting"], timeout=10)
if exp_pwd_1 == 0:
child.sendline(password_1)
elif exp_pwd_1 == 1:
child.sendline("yes")
child.sendline(password_1)
exp_pwd_2 = child.expect(["password:", "want to continue connecting"], timeout=10)
if exp_pwd_2 == 0:
child.sendline(password_2)
elif exp_pwd_2 == 1:
child.sendline("yes")
child.sendline(password_2)
child.expect(pexpect.EOF)
for line in child.before.decode("utf-8").split("\r\n"):
for sub_line in line.replace("\r", " ").split("ETA"):
logger.console(sub_line)
logger.console("\n")
output.append(line.replace("\r", " "))
msg = "scp: %s: " % dest
if msg + "Permission denied" in output or msg + "No such file or directory" in output:
logger.error("Please check the dest path: '%s' exists or have access" % dest)
elif "scp: /ome/virtuora: No such file or directory" % dest in output:
logger.error("Please check the dest path: '%s' exists or have access" % dest)
else:
status = True
except pexpect.exceptions.TIMEOUT:
if "Permission denied" in child.before.decode("utf-8") or "password:"\
in child.before.decode("utf-8"):
logger.error("Please check the username or password")
except pexpect.exceptions.EOF:
if "ld not resolve hostname" in child.before.decode("utf-8"):
logger.error("Please check the Hostnames: '%s', '%s'" % (host_1, host_2))
if status:
logger.console(src_check_sum)
dst_file = [dest + "/" + src.split("/")[-1]]
status, dst_check_sum = remote_file_operations.file_check_sum(user_2, host_2, password_2, dst_file)
if status:
for src_file, src_check in src_check_sum.items():
for dst_file, dst_check in dst_check_sum.items():
if src_file == dst_file and src_check == dst_check:
logger.console("%s Transfered Successfully" % (src_file))
status = True
else:
logger.console("Something went wrong in file transferring")
return status, output
I want the scp logic and checksum logic to be efficient.
