Source code for airflow.contrib.hooks.aws_glue_catalog_hook

# -*- coding: utf-8 -*-
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# 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.


from airflow.contrib.hooks.aws_hook import AwsHook


[docs]class AwsGlueCatalogHook(AwsHook): """ Interact with AWS Glue Catalog :param aws_conn_id: ID of the Airflow connection where credentials and extra configuration are stored :type aws_conn_id: str :param region_name: aws region name (example: us-east-1) :type region_name: str """ def __init__(self, aws_conn_id='aws_default', region_name=None, *args, **kwargs): self.region_name = region_name super(AwsGlueCatalogHook, self).__init__(aws_conn_id=aws_conn_id, *args, **kwargs)
[docs] def get_conn(self): """ Returns glue connection object. """ self.conn = self.get_client_type('glue', self.region_name) return self.conn
[docs] def get_partitions(self, database_name, table_name, expression='', page_size=None, max_items=None): """ Retrieves the partition values for a table. :param database_name: The name of the catalog database where the partitions reside. :type database_name: str :param table_name: The name of the partitions' table. :type table_name: str :param expression: An expression filtering the partitions to be returned. Please see official AWS documentation for further information. https://docs.aws.amazon.com/glue/latest/dg/aws-glue-api-catalog-partitions.html#aws-glue-api-catalog-partitions-GetPartitions :type expression: str :param page_size: pagination size :type page_size: int :param max_items: maximum items to return :type max_items: int :return: set of partition values where each value is a tuple since a partition may be composed of multiple columns. For example: ``{('2018-01-01','1'), ('2018-01-01','2')}`` """ config = { 'PageSize': page_size, 'MaxItems': max_items, } paginator = self.get_conn().get_paginator('get_partitions') response = paginator.paginate( DatabaseName=database_name, TableName=table_name, Expression=expression, PaginationConfig=config ) partitions = set() for page in response: for p in page['Partitions']: partitions.add(tuple(p['Values'])) return partitions
[docs] def check_for_partition(self, database_name, table_name, expression): """ Checks whether a partition exists :param database_name: Name of hive database (schema) @table belongs to :type database_name: str :param table_name: Name of hive table @partition belongs to :type table_name: str :expression: Expression that matches the partitions to check for (eg `a = 'b' AND c = 'd'`) :type expression: str :rtype: bool >>> hook = AwsGlueCatalogHook() >>> t = 'static_babynames_partitioned' >>> hook.check_for_partition('airflow', t, "ds='2015-01-01'") True """ partitions = self.get_partitions(database_name, table_name, expression, max_items=1) if partitions: return True else: return False
[docs] def get_table(self, database_name, table_name): """ Get the information of the table :param database_name: Name of hive database (schema) @table belongs to :type database_name: str :param table_name: Name of hive table :type table_name: str :rtype: dict >>> hook = AwsGlueCatalogHook() >>> r = hook.get_table('db', 'table_foo') >>> r['Name'] = 'table_foo' """ result = self.get_conn().get_table(DatabaseName=database_name, Name=table_name) return result['Table']
[docs] def get_table_location(self, database_name, table_name): """ Get the physical location of the table :param database_name: Name of hive database (schema) @table belongs to :type database_name: str :param table_name: Name of hive table :type table_name: str :return: str """ table = self.get_table(database_name, table_name) return table['StorageDescriptor']['Location']