#
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# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
"""This module contains SFTP operator."""
from __future__ import annotations
import os
import socket
from collections.abc import Sequence
from pathlib import Path
from typing import Any
import paramiko
from airflow.exceptions import AirflowException
from airflow.models import BaseOperator
from airflow.providers.sftp.hooks.sftp import SFTPHook
[docs]class SFTPOperation:
"""Operation that can be used with SFTP."""
[docs]class SFTPOperator(BaseOperator):
"""
SFTPOperator for transferring files from remote host to local or vice a versa.
This operator uses sftp_hook to open sftp transport channel that serve as basis for file transfer.
:param ssh_conn_id: :ref:`ssh connection id<howto/connection:ssh>`
from airflow Connections.
:param sftp_hook: predefined SFTPHook to use
Either `sftp_hook` or `ssh_conn_id` needs to be provided.
:param remote_host: remote host to connect (templated)
Nullable. If provided, it will replace the `remote_host` which was
defined in `sftp_hook` or predefined in the connection of `ssh_conn_id`.
:param local_filepath: local file path or list of local file paths to get or put. (templated)
:param remote_filepath: remote file path or list of remote file paths to get or put. (templated)
:param operation: specify operation 'get' or 'put', defaults to put
:param confirm: specify if the SFTP operation should be confirmed, defaults to True
: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,
)
"""
[docs] template_fields: Sequence[str] = ("local_filepath", "remote_filepath", "remote_host")
def __init__(
self,
*,
sftp_hook: SFTPHook | None = None,
ssh_conn_id: str | None = None,
remote_host: str | None = None,
local_filepath: str | list[str],
remote_filepath: str | list[str],
operation: str = SFTPOperation.PUT,
confirm: bool = True,
create_intermediate_dirs: bool = False,
**kwargs,
) -> None:
super().__init__(**kwargs)
self.sftp_hook = sftp_hook
self.ssh_conn_id = ssh_conn_id
self.remote_host = remote_host
self.operation = operation
self.confirm = confirm
self.create_intermediate_dirs = create_intermediate_dirs
self.local_filepath = local_filepath
self.remote_filepath = remote_filepath
[docs] def execute(self, context: Any) -> str | list[str] | None:
if isinstance(self.local_filepath, str):
local_filepath_array = [self.local_filepath]
else:
local_filepath_array = self.local_filepath
if isinstance(self.remote_filepath, str):
remote_filepath_array = [self.remote_filepath]
else:
remote_filepath_array = self.remote_filepath
if len(local_filepath_array) != len(remote_filepath_array):
raise ValueError(
f"{len(local_filepath_array)} paths in local_filepath "
f"!= {len(remote_filepath_array)} paths in remote_filepath"
)
if self.operation.lower() not in (SFTPOperation.GET, SFTPOperation.PUT):
raise TypeError(
f"Unsupported operation value {self.operation}, "
f"expected {SFTPOperation.GET} or {SFTPOperation.PUT}."
)
file_msg = None
try:
if self.ssh_conn_id:
if self.sftp_hook and isinstance(self.sftp_hook, SFTPHook):
self.log.info("ssh_conn_id is ignored when sftp_hook is provided.")
else:
self.log.info("sftp_hook not provided or invalid. Trying ssh_conn_id to create SFTPHook.")
self.sftp_hook = SFTPHook(ssh_conn_id=self.ssh_conn_id)
if not self.sftp_hook:
raise AirflowException("Cannot operate without sftp_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 sftp_hook or predefined in connection of ssh_conn_id."
)
self.sftp_hook.remote_host = self.remote_host
for _local_filepath, _remote_filepath in zip(local_filepath_array, remote_filepath_array):
if self.operation.lower() == SFTPOperation.GET:
local_folder = os.path.dirname(_local_filepath)
if self.create_intermediate_dirs:
Path(local_folder).mkdir(parents=True, exist_ok=True)
file_msg = f"from {_remote_filepath} to {_local_filepath}"
self.log.info("Starting to transfer %s", file_msg)
self.sftp_hook.retrieve_file(_remote_filepath, _local_filepath)
else:
remote_folder = os.path.dirname(_remote_filepath)
if self.create_intermediate_dirs:
self.sftp_hook.create_directory(remote_folder)
file_msg = f"from {_local_filepath} to {_remote_filepath}"
self.log.info("Starting to transfer file %s", file_msg)
self.sftp_hook.store_file(_remote_filepath, _local_filepath, confirm=self.confirm)
except Exception as e:
raise AirflowException(f"Error while transferring {file_msg}, error: {e}")
return self.local_filepath
[docs] def get_openlineage_facets_on_start(self):
"""
Return OpenLineage datasets.
Dataset will have the following structure:
input: file://<local_host>/path
output: file://<remote_host>:<remote_port>/path.
"""
from airflow.providers.common.compat.openlineage.facet import Dataset
from airflow.providers.openlineage.extractors import OperatorLineage
scheme = "file"
local_host = socket.gethostname()
try:
local_host = socket.gethostbyname(local_host)
except Exception as e:
self.log.warning(
"Failed to resolve local hostname. "
"Using the hostname got by socket.gethostbyname() without resolution. %s",
e,
exc_info=True,
)
hook = self.sftp_hook or SFTPHook(ssh_conn_id=self.ssh_conn_id)
if self.remote_host is not None:
remote_host = self.remote_host
else:
remote_host = hook.get_connection(hook.ssh_conn_id).host
try:
remote_host = socket.gethostbyname(remote_host)
except OSError as e:
self.log.warning(
"Failed to resolve remote hostname. Using the provided hostname without resolution. %s",
e,
exc_info=True,
)
if hasattr(hook, "port"):
remote_port = hook.port
# Since v4.1.0, SFTPOperator accepts both a string (single file) and a list of
# strings (multiple files) as local_filepath and remote_filepath, and internally
# keeps them as list in both cases. But before 4.1.0, only single string is
# allowed. So we consider both cases here for backward compatibility.
if isinstance(self.local_filepath, str):
local_filepath = [self.local_filepath]
else:
local_filepath = self.local_filepath
if isinstance(self.remote_filepath, str):
remote_filepath = [self.remote_filepath]
else:
remote_filepath = self.remote_filepath
local_datasets = [
Dataset(namespace=self._get_namespace(scheme, local_host, None, path), name=path)
for path in local_filepath
]
remote_datasets = [
Dataset(namespace=self._get_namespace(scheme, remote_host, remote_port, path), name=path)
for path in remote_filepath
]
if self.operation.lower() == SFTPOperation.GET:
inputs = remote_datasets
outputs = local_datasets
else:
inputs = local_datasets
outputs = remote_datasets
return OperatorLineage(
inputs=inputs,
outputs=outputs,
)
def _get_namespace(self, scheme, host, port, path) -> str:
port = port or paramiko.config.SSH_PORT
authority = f"{host}:{port}"
return f"{scheme}://{authority}"