Source code for airflow.contrib.hooks.snowflake_hook

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import snowflake.connector
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import serialization

from airflow.hooks.dbapi_hook import DbApiHook

[docs]class SnowflakeHook(DbApiHook): """ Interact with Snowflake. get_sqlalchemy_engine() depends on snowflake-sqlalchemy """
[docs] conn_name_attr = 'snowflake_conn_id'
[docs] default_conn_name = 'snowflake_default'
[docs] supports_autocommit = True
def __init__(self, *args, **kwargs): super(SnowflakeHook, self).__init__(*args, **kwargs) self.account = kwargs.pop("account", None) self.warehouse = kwargs.pop("warehouse", None) self.database = kwargs.pop("database", None) self.region = kwargs.pop("region", None) self.role = kwargs.pop("role", None) self.schema = kwargs.pop("schema", None) self.authenticator = kwargs.pop("authenticator", None)
[docs] def _get_conn_params(self): """ one method to fetch connection params as a dict used in get_uri() and get_connection() """ conn = self.get_connection(self.snowflake_conn_id) account = conn.extra_dejson.get('account', None) warehouse = conn.extra_dejson.get('warehouse', None) database = conn.extra_dejson.get('database', None) region = conn.extra_dejson.get("region", None) role = conn.extra_dejson.get('role', None) authenticator = conn.extra_dejson.get('authenticator', 'snowflake') conn_config = { "user": conn.login, "password": conn.password or '', "schema": self.schema or conn.schema or '', "database": self.database or database or '', "account": self.account or account or '', "warehouse": self.warehouse or warehouse or '', "region": self.region or region or '', "role": self.role or role, "authenticator": self.authenticator or authenticator } """ If private_key_file is specified in the extra json, load the contents of the file as a private key and specify that in the connection configuration. The connection password then becomes the passphrase for the private key. If your private key file is not encrypted (not recommended), then leave the password empty. """ private_key_file = conn.extra_dejson.get('private_key_file', None) if private_key_file: with open(private_key_file, "rb") as key: passphrase = None if conn.password: passphrase = conn.password.strip().encode() p_key = serialization.load_pem_private_key(, password=passphrase, backend=default_backend() ) pkb = p_key.private_bytes(encoding=serialization.Encoding.DER, format=serialization.PrivateFormat.PKCS8, encryption_algorithm=serialization.NoEncryption()) conn_config['private_key'] = pkb conn_config.pop('password', None) return conn_config
[docs] def get_uri(self): """ override DbApiHook get_uri method for get_sqlalchemy_engine() """ conn_config = self._get_conn_params() uri = 'snowflake://{user}:{password}@{account}/{database}/' uri += '{schema}?warehouse={warehouse}&role={role}&authenticator={authenticator}' return uri.format(**conn_config)
[docs] def get_conn(self): """ Returns a snowflake.connection object """ conn_config = self._get_conn_params() conn = snowflake.connector.connect(**conn_config) return conn
[docs] def _get_aws_credentials(self): """ returns aws_access_key_id, aws_secret_access_key from extra intended to be used by external import and export statements """ if self.snowflake_conn_id: connection_object = self.get_connection(self.snowflake_conn_id) if 'aws_secret_access_key' in connection_object.extra_dejson: aws_access_key_id = connection_object.extra_dejson.get( 'aws_access_key_id') aws_secret_access_key = connection_object.extra_dejson.get( 'aws_secret_access_key') return aws_access_key_id, aws_secret_access_key
[docs] def set_autocommit(self, conn, autocommit): conn.autocommit(autocommit)

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