Source code for airflow.providers.microsoft.azure.secrets.azure_key_vault
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from typing import Optional
from azure.core.exceptions import ResourceNotFoundError
from azure.identity import DefaultAzureCredential
from azure.keyvault.secrets import SecretClient
try:
from functools import cached_property
except ImportError:
from cached_property import cached_property
from airflow.secrets import BaseSecretsBackend
from airflow.utils.log.logging_mixin import LoggingMixin
[docs]class AzureKeyVaultBackend(BaseSecretsBackend, LoggingMixin):
"""
Retrieves Airflow Connections or Variables from Azure Key Vault secrets.
The Azure Key Vault can be configured as a secrets backend in the ``airflow.cfg``:
.. code-block:: ini
[secrets]
backend = airflow.providers.microsoft.azure.secrets.azure_key_vault.AzureKeyVaultBackend
backend_kwargs = {"connections_prefix": "airflow-connections", "vault_url": "<azure_key_vault_uri>"}
For example, if the secrets prefix is ``airflow-connections-smtp-default``, this would be accessible
if you provide ``{"connections_prefix": "airflow-connections"}`` and request conn_id ``smtp-default``.
And if variables prefix is ``airflow-variables-hello``, this would be accessible
if you provide ``{"variables_prefix": "airflow-variables"}`` and request variable key ``hello``.
:param connections_prefix: Specifies the prefix of the secret to read to get Connections
If set to None (null), requests for connections will not be sent to Azure Key Vault
:type connections_prefix: str
:param variables_prefix: Specifies the prefix of the secret to read to get Variables
If set to None (null), requests for variables will not be sent to Azure Key Vault
:type variables_prefix: str
:param config_prefix: Specifies the prefix of the secret to read to get Variables.
If set to None (null), requests for configurations will not be sent to Azure Key Vault
:type config_prefix: str
:param vault_url: The URL of an Azure Key Vault to use
:type vault_url: str
:param sep: separator used to concatenate secret_prefix and secret_id. Default: "-"
:type sep: str
"""
def __init__(
self,
connections_prefix: str = 'airflow-connections',
variables_prefix: str = 'airflow-variables',
config_prefix: str = 'airflow-config',
vault_url: str = '',
sep: str = '-',
**kwargs,
) -> None:
super().__init__()
self.vault_url = vault_url
if connections_prefix is not None:
self.connections_prefix = connections_prefix.rstrip(sep)
else:
self.connections_prefix = connections_prefix
if variables_prefix is not None:
self.variables_prefix = variables_prefix.rstrip(sep)
else:
self.variables_prefix = variables_prefix
if config_prefix is not None:
self.config_prefix = config_prefix.rstrip(sep)
else:
self.config_prefix = config_prefix
self.sep = sep
self.kwargs = kwargs
@cached_property
[docs] def client(self) -> SecretClient:
"""Create a Azure Key Vault client."""
credential = DefaultAzureCredential()
client = SecretClient(vault_url=self.vault_url, credential=credential, **self.kwargs)
return client
[docs] def get_conn_uri(self, conn_id: str) -> Optional[str]:
"""
Get an Airflow Connection URI from an Azure Key Vault secret
:param conn_id: The Airflow connection id to retrieve
:type conn_id: str
"""
if self.connections_prefix is None:
return None
return self._get_secret(self.connections_prefix, conn_id)
[docs] def get_variable(self, key: str) -> Optional[str]:
"""
Get an Airflow Variable from an Azure Key Vault secret.
:param key: Variable Key
:type key: str
:return: Variable Value
"""
if self.variables_prefix is None:
return None
return self._get_secret(self.variables_prefix, key)
[docs] def get_config(self, key: str) -> Optional[str]:
"""
Get Airflow Configuration
:param key: Configuration Option Key
:return: Configuration Option Value
"""
if self.config_prefix is None:
return None
return self._get_secret(self.config_prefix, key)
@staticmethod
[docs] def build_path(path_prefix: str, secret_id: str, sep: str = '-') -> str:
"""
Given a path_prefix and secret_id, build a valid secret name for the Azure Key Vault Backend.
Also replaces underscore in the path with dashes to support easy switching between
environment variables, so ``connection_default`` becomes ``connection-default``.
:param path_prefix: The path prefix of the secret to retrieve
:type path_prefix: str
:param secret_id: Name of the secret
:type secret_id: str
:param sep: Separator used to concatenate path_prefix and secret_id
:type sep: str
"""
path = f'{path_prefix}{sep}{secret_id}'
return path.replace('_', sep)
[docs] def _get_secret(self, path_prefix: str, secret_id: str) -> Optional[str]:
"""
Get an Azure Key Vault secret value
:param path_prefix: Prefix for the Path to get Secret
:type path_prefix: str
:param secret_id: Secret Key
:type secret_id: str
"""
name = self.build_path(path_prefix, secret_id, self.sep)
try:
secret = self.client.get_secret(name=name)
return secret.value
except ResourceNotFoundError as ex:
self.log.debug('Secret %s not found: %s', name, ex)
return None