How to define operations of an STFP Operator on Airflow?

Question

class SFTPOperation(object):
    PUT = 'put'
    GET = 'get'  

operation=SFTPOperation.GET,
NameError: name 'SFTPOperation' is not defined

I have defined operators here but I can't find anything on the internet related to operations

class sftpplugin(AirflowPlugin):
    name = "sftp_plugin"
    operators = [SFTPOperator]

Any help would appreciated!

Thanks,

Answer 1

By noticing that the SFTP operator uses ssh_hook to open an sftp transport channel, you should need to provide ssh_hook or ssh_conn_id for file transfer. First, let's see an example providing the parameter ssh_conn_id.

from airflow.providers.sftp.operators import sftp_operator
from airflow import DAG
import datetime

dag = DAG(
'test_dag',
start_date = datetime.datetime(2020,1,8,0,0,0),
schedule_interval = '@daily'
)

put_operation = SFTPOperator(
            task_id="operation",
            ssh_conn_id="ssh_default",
            local_filepath="route_to_local_file",
            remote_filepath="remote_route_to_copy",
            operation="put",
            dag=dag
            )
get_operation = SFTPOperator(....,
            operation = "get",
            dag = dag
            )

put_operation >> get_operation

Notice that the dag should be scheduled as needed by your task, here the example considers a daily schedule starting at noon. Now, If you're providing the SSHhook, the following changes to the above code are necessary

from airflow.contrib.hooks.ssh_hook import SSHHook
...

put_operation = SFTPOperator(
            task_id="operation",
            ssh_hook=SSHHook("Name_of_variable_defined"),
            ...
            dag=dag
            )
....

where "Name_of_variable_defined" is created in Admin -> Connections at the interface of Airflow.