Source code for generic_transfer

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import logging

from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults
from airflow.hooks.base_hook import BaseHook


[docs]class GenericTransfer(BaseOperator): """ Moves data from a connection to another, assuming that they both provide the required methods in their respective hooks. The source hook needs to expose a `get_records` method, and the destination a `insert_rows` method. This is mean to be used on small-ish datasets that fit in memory. :param sql: SQL query to execute against the source database :type sql: str :param destination_table: target table :type destination_table: str :param source_conn_id: source connection :type source_conn_id: str :param destination_conn_id: source connection :type destination_conn_id: str :param preoperator: sql statement or list of statements to be executed prior to loading the data :type preoperator: str or list of str """ template_fields = ('sql', 'destination_table', 'preoperator') template_ext = ('.sql', '.hql',) ui_color = '#b0f07c' @apply_defaults def __init__( self, sql, destination_table, source_conn_id, destination_conn_id, preoperator=None, *args, **kwargs): super(GenericTransfer, self).__init__(*args, **kwargs) self.sql = sql self.destination_table = destination_table self.source_conn_id = source_conn_id self.destination_conn_id = destination_conn_id self.preoperator = preoperator def execute(self, context): source_hook = BaseHook.get_hook(self.source_conn_id) logging.info("Extracting data from {}".format(self.source_conn_id)) logging.info("Executing: \n" + self.sql) results = source_hook.get_records(self.sql) destination_hook = BaseHook.get_hook(self.destination_conn_id) if self.preoperator: logging.info("Running preoperator") logging.info(self.preoperator) destination_hook.run(self.preoperator) logging.info("Inserting rows into {}".format(self.destination_conn_id)) destination_hook.insert_rows(table=self.destination_table, rows=results)