Source code for hive_to_mysql

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# http://www.apache.org/licenses/LICENSE-2.0
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from airflow.hooks.hive_hooks import HiveServer2Hook
from airflow.hooks.mysql_hook import MySqlHook
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults

from tempfile import NamedTemporaryFile


[docs]class HiveToMySqlTransfer(BaseOperator): """ Moves data from Hive to MySQL, note that for now the data is loaded into memory before being pushed to MySQL, so this operator should be used for smallish amount of data. :param sql: SQL query to execute against the MySQL database :type sql: str :param mysql_table: target MySQL table, use dot notation to target a specific database :type mysql_table: str :param mysql_conn_id: source mysql connection :type mysql_conn_id: str :param hiveserver2_conn_id: destination hive connection :type hiveserver2_conn_id: str :param mysql_preoperator: sql statement to run against mysql prior to import, typically use to truncate of delete in place of the data coming in, allowing the task to be idempotent (running the task twice won't double load data) :type mysql_preoperator: str :param mysql_postoperator: sql statement to run against mysql after the import, typically used to move data from staging to production and issue cleanup commands. :type mysql_postoperator: str :param bulk_load: flag to use bulk_load option. This loads mysql directly from a tab-delimited text file using the LOAD DATA LOCAL INFILE command. This option requires an extra connection parameter for the destination MySQL connection: {'local_infile': true}. :type bulk_load: bool """ template_fields = ('sql', 'mysql_table', 'mysql_preoperator', 'mysql_postoperator') template_ext = ('.sql',) ui_color = '#a0e08c' @apply_defaults def __init__( self, sql, mysql_table, hiveserver2_conn_id='hiveserver2_default', mysql_conn_id='mysql_default', mysql_preoperator=None, mysql_postoperator=None, bulk_load=False, *args, **kwargs): super(HiveToMySqlTransfer, self).__init__(*args, **kwargs) self.sql = sql self.mysql_table = mysql_table self.mysql_conn_id = mysql_conn_id self.mysql_preoperator = mysql_preoperator self.mysql_postoperator = mysql_postoperator self.hiveserver2_conn_id = hiveserver2_conn_id self.bulk_load = bulk_load def execute(self, context): hive = HiveServer2Hook(hiveserver2_conn_id=self.hiveserver2_conn_id) self.log.info("Extracting data from Hive: %s", self.sql) if self.bulk_load: tmpfile = NamedTemporaryFile() hive.to_csv(self.sql, tmpfile.name, delimiter='\t', lineterminator='\n', output_header=False) else: results = hive.get_records(self.sql) mysql = MySqlHook(mysql_conn_id=self.mysql_conn_id) if self.mysql_preoperator: self.log.info("Running MySQL preoperator") mysql.run(self.mysql_preoperator) self.log.info("Inserting rows into MySQL") if self.bulk_load: mysql.bulk_load(table=self.mysql_table, tmp_file=tmpfile.name) tmpfile.close() else: mysql.insert_rows(table=self.mysql_table, rows=results) if self.mysql_postoperator: self.log.info("Running MySQL postoperator") mysql.run(self.mysql_postoperator) self.log.info("Done.")