Source code for airflow.providers.google.cloud.transfers.oracle_to_gcs

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# pylint: disable=c-extension-no-member
import base64
import calendar
from datetime import date, datetime, timedelta
from decimal import Decimal
from typing import Dict

import cx_Oracle

from airflow.providers.google.cloud.transfers.sql_to_gcs import BaseSQLToGCSOperator
from airflow.providers.oracle.hooks.oracle import OracleHook
from airflow.utils.decorators import apply_defaults


[docs]class OracleToGCSOperator(BaseSQLToGCSOperator): """Copy data from Oracle to Google Cloud Storage in JSON or CSV format. .. seealso:: For more information on how to use this operator, take a look at the guide: :ref:`howto/operator:OracleToGCSOperator` :param oracle_conn_id: Reference to a specific Oracle hook. :type oracle_conn_id: str :param ensure_utc: Ensure TIMESTAMP columns exported as UTC. If set to `False`, TIMESTAMP columns will be exported using the Oracle server's default timezone. :type ensure_utc: bool """
[docs] ui_color = '#a0e08c'
[docs] type_map = { cx_Oracle.DB_TYPE_BINARY_DOUBLE: 'DECIMAL', cx_Oracle.DB_TYPE_BINARY_FLOAT: 'DECIMAL', cx_Oracle.DB_TYPE_BINARY_INTEGER: 'INTEGER', cx_Oracle.DB_TYPE_BOOLEAN: 'BOOLEAN', cx_Oracle.DB_TYPE_DATE: 'TIMESTAMP', cx_Oracle.DB_TYPE_NUMBER: 'NUMERIC', cx_Oracle.DB_TYPE_TIMESTAMP: 'TIMESTAMP', cx_Oracle.DB_TYPE_TIMESTAMP_LTZ: 'TIMESTAMP', cx_Oracle.DB_TYPE_TIMESTAMP_TZ: 'TIMESTAMP',
} @apply_defaults def __init__(self, *, oracle_conn_id='oracle_default', ensure_utc=False, **kwargs): super().__init__(**kwargs) self.ensure_utc = ensure_utc self.oracle_conn_id = oracle_conn_id
[docs] def query(self): """Queries Oracle and returns a cursor to the results.""" oracle = OracleHook(oracle_conn_id=self.oracle_conn_id) conn = oracle.get_conn() cursor = conn.cursor() if self.ensure_utc: # Ensure TIMESTAMP results are in UTC tz_query = "SET time_zone = '+00:00'" self.log.info('Executing: %s', tz_query) cursor.execute(tz_query) self.log.info('Executing: %s', self.sql) cursor.execute(self.sql) return cursor
[docs] def field_to_bigquery(self, field) -> Dict[str, str]: field_type = self.type_map.get(field[1], "STRING") field_mode = "NULLABLE" if not field[6] or field_type == "TIMESTAMP" else "REQUIRED" return { 'name': field[0], 'type': field_type, 'mode': field_mode,
}
[docs] def convert_type(self, value, schema_type): """ Takes a value from Oracle db, and converts it to a value that's safe for JSON/Google Cloud Storage/BigQuery. * Datetimes are converted to UTC seconds. * Decimals are converted to floats. * Dates are converted to ISO formatted string if given schema_type is DATE, or UTC seconds otherwise. * Binary type fields are converted to integer if given schema_type is INTEGER, or encoded with base64 otherwise. Imported BYTES data must be base64-encoded according to BigQuery documentation: https://cloud.google.com/bigquery/data-types :param value: Oracle db column value :type value: Any :param schema_type: BigQuery data type :type schema_type: str """ if value is None: return value if isinstance(value, datetime): value = calendar.timegm(value.timetuple()) elif isinstance(value, timedelta): value = value.total_seconds() elif isinstance(value, Decimal): value = float(value) elif isinstance(value, date): if schema_type == "DATE": value = value.isoformat() else: value = calendar.timegm(value.timetuple()) elif isinstance(value, bytes): if schema_type == "INTEGER": value = int.from_bytes(value, "big") else: value = base64.standard_b64encode(value).decode('ascii') return value

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