# -*- coding: utf-8 -*-
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import os
from airflow.contrib.hooks.ssh_hook import SSHHook
from airflow.exceptions import AirflowException
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults
class SFTPOperation(object):
PUT = 'put'
GET = 'get'
[docs]class SFTPOperator(BaseOperator):
"""
SFTPOperator for transferring files from remote host to local or vice a versa.
This operator uses ssh_hook to open sftp transport channel that serve as basis
for file transfer.
:param ssh_hook: predefined ssh_hook to use for remote execution.
Either `ssh_hook` or `ssh_conn_id` needs to be provided.
:type ssh_hook: :class:`SSHHook`
:param ssh_conn_id: connection id from airflow Connections.
`ssh_conn_id` will be ingored if `ssh_hook` is provided.
:type ssh_conn_id: str
:param remote_host: remote host to connect (templated)
Nullable. If provided, it will replace the `remote_host` which was
defined in `ssh_hook` or predefined in the connection of `ssh_conn_id`.
:type remote_host: str
:param local_filepath: local file path to get or put. (templated)
:type local_filepath: str
:param remote_filepath: remote file path to get or put. (templated)
:type remote_filepath: str
:param operation: specify operation 'get' or 'put', defaults to put
:type operation: str
:param confirm: specify if the SFTP operation should be confirmed, defaults to True
:type confirm: bool
:param create_intermediate_dirs: create missing intermediate directories when
copying from remote to local and vice-versa. Default is False.
Example: The following task would copy ``file.txt`` to the remote host
at ``/tmp/tmp1/tmp2/`` while creating ``tmp``,``tmp1`` and ``tmp2`` if they
don't exist. If the parameter is not passed it would error as the directory
does not exist. ::
put_file = SFTPOperator(
task_id="test_sftp",
ssh_conn_id="ssh_default",
local_filepath="/tmp/file.txt",
remote_filepath="/tmp/tmp1/tmp2/file.txt",
operation="put",
create_intermediate_dirs=True,
dag=dag
)
:type create_intermediate_dirs: bool
"""
template_fields = ('local_filepath', 'remote_filepath', 'remote_host')
@apply_defaults
def __init__(self,
ssh_hook=None,
ssh_conn_id=None,
remote_host=None,
local_filepath=None,
remote_filepath=None,
operation=SFTPOperation.PUT,
confirm=True,
create_intermediate_dirs=False,
*args,
**kwargs):
super(SFTPOperator, self).__init__(*args, **kwargs)
self.ssh_hook = ssh_hook
self.ssh_conn_id = ssh_conn_id
self.remote_host = remote_host
self.local_filepath = local_filepath
self.remote_filepath = remote_filepath
self.operation = operation
self.confirm = confirm
self.create_intermediate_dirs = create_intermediate_dirs
if not (self.operation.lower() == SFTPOperation.GET or
self.operation.lower() == SFTPOperation.PUT):
raise TypeError("unsupported operation value {0}, expected {1} or {2}"
.format(self.operation, SFTPOperation.GET, SFTPOperation.PUT))
def execute(self, context):
file_msg = None
try:
if self.ssh_conn_id:
if self.ssh_hook and isinstance(self.ssh_hook, SSHHook):
self.log.info("ssh_conn_id is ignored when ssh_hook is provided.")
else:
self.log.info("ssh_hook is not provided or invalid. " +
"Trying ssh_conn_id to create SSHHook.")
self.ssh_hook = SSHHook(ssh_conn_id=self.ssh_conn_id)
if not self.ssh_hook:
raise AirflowException("Cannot operate without ssh_hook or ssh_conn_id.")
if self.remote_host is not None:
self.log.info("remote_host is provided explicitly. " +
"It will replace the remote_host which was defined " +
"in ssh_hook or predefined in connection of ssh_conn_id.")
self.ssh_hook.remote_host = self.remote_host
with self.ssh_hook.get_conn() as ssh_client:
sftp_client = ssh_client.open_sftp()
if self.operation.lower() == SFTPOperation.GET:
local_folder = os.path.dirname(self.local_filepath)
if self.create_intermediate_dirs:
# Create Intermediate Directories if it doesn't exist
try:
os.makedirs(local_folder)
except OSError:
if not os.path.isdir(local_folder):
raise
file_msg = "from {0} to {1}".format(self.remote_filepath,
self.local_filepath)
self.log.debug("Starting to transfer %s", file_msg)
sftp_client.get(self.remote_filepath, self.local_filepath)
else:
remote_folder = os.path.dirname(self.remote_filepath)
if self.create_intermediate_dirs:
_make_intermediate_dirs(
sftp_client=sftp_client,
remote_directory=remote_folder,
)
file_msg = "from {0} to {1}".format(self.local_filepath,
self.remote_filepath)
self.log.debug("Starting to transfer file %s", file_msg)
sftp_client.put(self.local_filepath,
self.remote_filepath,
confirm=self.confirm)
except Exception as e:
raise AirflowException("Error while transferring {0}, error: {1}"
.format(file_msg, str(e)))
return None
def _make_intermediate_dirs(sftp_client, remote_directory):
"""
Create all the intermediate directories in a remote host
:param sftp_client: A Paramiko SFTP client.
:param remote_directory: Absolute Path of the directory containing the file
:return:
"""
if remote_directory == '/':
sftp_client.chdir('/')
return
if remote_directory == '':
return
try:
sftp_client.chdir(remote_directory)
except IOError:
dirname, basename = os.path.split(remote_directory.rstrip('/'))
_make_intermediate_dirs(sftp_client, dirname)
sftp_client.mkdir(basename)
sftp_client.chdir(basename)
return