Source code for airflow.operators.redshift_to_s3_operator

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Transfers data from AWS Redshift into a S3 Bucket.

from airflow.hooks.postgres_hook import PostgresHook
from airflow.hooks.S3_hook import S3Hook
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults

[docs]class RedshiftToS3Transfer(BaseOperator): """ Executes an UNLOAD command to s3 as a CSV with headers :param schema: reference to a specific schema in redshift database :type schema: str :param table: reference to a specific table in redshift database :type table: str :param s3_bucket: reference to a specific S3 bucket :type s3_bucket: str :param s3_key: reference to a specific S3 key. If ``table_as_file_name`` is set to False, this param must include the desired file name :type s3_key: str :param redshift_conn_id: reference to a specific redshift database :type redshift_conn_id: str :param aws_conn_id: reference to a specific S3 connection :type aws_conn_id: str :param verify: Whether or not to verify SSL certificates for S3 connection. By default SSL certificates are verified. You can provide the following values: - ``False``: do not validate SSL certificates. SSL will still be used (unless use_ssl is False), but SSL certificates will not be verified. - ``path/to/cert/bundle.pem``: A filename of the CA cert bundle to uses. You can specify this argument if you want to use a different CA cert bundle than the one used by botocore. :type verify: bool or str :param unload_options: reference to a list of UNLOAD options :type unload_options: list :param autocommit: If set to True it will automatically commit the UNLOAD statement. Otherwise it will be committed right before the redshift connection gets closed. :type autocommit: bool :param include_header: If set to True the s3 file contains the header columns. :type include_header: bool :param table_as_file_name: If set to True, the s3 file will be named as the table :type table_as_file_name: bool """
[docs] template_fields = ()
[docs] template_ext = ()
[docs] ui_color = '#ededed'
@apply_defaults def __init__( # pylint: disable=too-many-arguments self, schema, table, s3_bucket, s3_key, redshift_conn_id='redshift_default', aws_conn_id='aws_default', verify=None, unload_options=tuple(), autocommit=False, include_header=False, table_as_file_name=True, # Set to True by default for not breaking current workflows *args, **kwargs): super(RedshiftToS3Transfer, self).__init__(*args, **kwargs) self.schema = schema self.table = table self.s3_bucket = s3_bucket self.s3_key = s3_key self.redshift_conn_id = redshift_conn_id self.aws_conn_id = aws_conn_id self.verify = verify self.unload_options = unload_options self.autocommit = autocommit self.include_header = include_header self.table_as_file_name = table_as_file_name if self.include_header and 'HEADER' not in [uo.upper().strip() for uo in self.unload_options]: self.unload_options = list(self.unload_options) + ['HEADER', ]
[docs] def execute(self, context): postgres_hook = PostgresHook(postgres_conn_id=self.redshift_conn_id) s3_hook = S3Hook(aws_conn_id=self.aws_conn_id, verify=self.verify) credentials = s3_hook.get_credentials() unload_options = '\n\t\t\t'.join(self.unload_options) s3_key = '{}/{}_'.format(self.s3_key, self.table) if self.table_as_file_name else self.s3_key select_query = "SELECT * FROM {schema}.{table}".format(schema=self.schema, table=self.table) unload_query = """ UNLOAD ('{select_query}') TO 's3://{s3_bucket}/{s3_key}' with credentials 'aws_access_key_id={access_key};aws_secret_access_key={secret_key}' {unload_options}; """.format(select_query=select_query, s3_bucket=self.s3_bucket, s3_key=s3_key, access_key=credentials.access_key, secret_key=credentials.secret_key, unload_options=unload_options)'Executing UNLOAD command...'), self.autocommit)"UNLOAD command complete...")

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