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Azure Key Vault Keys client library for Python - version 4.10.0

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Azure Key Vault helps solve the following problems:

  • Cryptographic key management (this library) - create, store, and control access to the keys used to encrypt your data
  • Secrets management (azure-keyvault-secrets) - securely store and control access to tokens, passwords, certificates, API keys, and other secrets
  • Certificate management (azure-keyvault-certificates) - create, manage, and deploy public and private SSL/TLS certificates
  • Vault administration (azure-keyvault-administration) - role-based access control (RBAC), and vault-level backup and restore options

Source code | Package (PyPI) | Package (Conda) | API reference documentation | Product documentation | Samples

Disclaimer

Azure SDK Python packages support for Python 2.7 has ended 01 January 2022. For more information and questions, please refer to https://github.com/Azure/azure-sdk-for-python/issues/20691.

Python 3.8 or later is required to use this package. For more details, please refer to Azure SDK for Python version support policy.

Getting started

Install the package

Install azure-keyvault-keys and azure-identity with pip:

pip install azure-keyvault-keys azure-identity

azure-identity is used for Azure Active Directory authentication as demonstrated below.

Prerequisites

Authenticate the client

In order to interact with the Azure Key Vault service, you will need an instance of a KeyClient, as well as a vault URL and a credential object. This document demonstrates using a DefaultAzureCredential, which is appropriate for most scenarios. We recommend using a managed identity for authentication in production environments.

See azure-identity documentation for more information about other methods of authentication and their corresponding credential types.

Create a client

After configuring your environment for the DefaultAzureCredential to use a suitable method of authentication, you can do the following to create a key client (replacing the value of VAULT_URL with your vault's URL):

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

VAULT_URL = os.environ["VAULT_URL"]
credential = DefaultAzureCredential()
client = KeyClient(vault_url=VAULT_URL, credential=credential)

NOTE: For an asynchronous client, import azure.keyvault.keys.aio's KeyClient instead.

Key concepts

Keys

Azure Key Vault can create and store RSA and elliptic curve keys. Both can optionally be protected by hardware security modules (HSMs). Azure Key Vault can also perform cryptographic operations with them. For more information about keys and supported operations and algorithms, see the Key Vault documentation.

KeyClient can create keys in the vault, get existing keys from the vault, update key metadata, and delete keys, as shown in the examples below.

Examples

This section contains code snippets covering common tasks:

Create a key

The create_key method can be used by a KeyClient to create a key of any type -- alternatively, specific helpers such as create_rsa_key and create_ec_key create RSA and elliptic curve keys in the vault, respectively. If a key with the same name already exists, a new version of that key is created.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

credential = DefaultAzureCredential()

key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)

# Create an RSA key
rsa_key = key_client.create_rsa_key("rsa-key-name", size=2048)
print(rsa_key.name)
print(rsa_key.key_type)

# Create an elliptic curve key
ec_key = key_client.create_ec_key("ec-key-name", curve="P-256")
print(ec_key.name)
print(ec_key.key_type)

Retrieve a key

get_key retrieves a key previously stored in the Vault.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

credential = DefaultAzureCredential()

key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
key = key_client.get_key("key-name")
print(key.name)

Update an existing key

update_key_properties updates the properties of a key previously stored in the Key Vault.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

credential = DefaultAzureCredential()

key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)

# we will now disable the key for further use
updated_key = key_client.update_key_properties("key-name", enabled=False)

print(updated_key.name)
print(updated_key.properties.enabled)

Delete a key

begin_delete_key requests Key Vault delete a key, returning a poller which allows you to wait for the deletion to finish. Waiting is helpful when the vault has soft-delete enabled, and you want to purge (permanently delete) the key as soon as possible. When soft-delete is disabled, begin_delete_key itself is permanent.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

credential = DefaultAzureCredential()

key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
deleted_key = key_client.begin_delete_key("key-name").result()

print(deleted_key.name)
print(deleted_key.deleted_date)

Configure automatic key rotation

update_key_rotation_policy can be used by a KeyClient to configure automatic key rotation for a key by specifying a rotation policy.

from azure.keyvault.keys import KeyRotationLifetimeAction, KeyRotationPolicy, KeyRotationPolicyAction

# Here we set the key's automated rotation policy to rotate the key two months after the key was created.
# If you pass an empty KeyRotationPolicy() as the `policy` parameter, the rotation policy will be set to the
# default policy. Any keyword arguments will update specified properties of the policy.
actions = [KeyRotationLifetimeAction(KeyRotationPolicyAction.rotate, time_after_create="P2M")]
updated_policy = client.update_key_rotation_policy(
    "rotation-sample-key", policy=KeyRotationPolicy(), expires_in="P90D", lifetime_actions=actions
)
assert updated_policy.expires_in == "P90D"

In addition, rotate_key allows you to rotate a key on-demand by creating a new version of the given key.

rotated_key = client.rotate_key("rotation-sample-key")
print(f"Rotated the key on-demand; new version is {rotated_key.properties.version}")

List keys

list_properties_of_keys lists the properties of all of the keys in the client's vault.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient

credential = DefaultAzureCredential()

key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
keys = key_client.list_properties_of_keys()

for key in keys:
    # the list doesn't include values or versions of the keys
    print(key.name)

Cryptographic operations

CryptographyClient enables cryptographic operations (encrypt/decrypt, wrap/unwrap, sign/verify) using a particular key.

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient
from azure.keyvault.keys.crypto import CryptographyClient, EncryptionAlgorithm

credential = DefaultAzureCredential()
key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)

key = key_client.get_key("key-name")
crypto_client = CryptographyClient(key, credential=credential)
plaintext = b"plaintext"

result = crypto_client.encrypt(EncryptionAlgorithm.rsa_oaep, plaintext)
decrypted = crypto_client.decrypt(result.algorithm, result.ciphertext)

See the package documentation for more details of the cryptography API.

Async API

This library includes a complete set of async APIs. To use them, you must first install an async transport, such as aiohttp. See azure-core documentation for more information.

Async clients and credentials should be closed when they're no longer needed. These objects are async context managers and define async close methods. For example:

from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.keys.aio import KeyClient

credential = DefaultAzureCredential()

# call close when the client and credential are no longer needed
client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
...
await client.close()
await credential.close()

# alternatively, use them as async context managers (contextlib.AsyncExitStack can help)
client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
async with client:
  async with credential:
    ...

Asynchronously create a key

create_rsa_key and create_ec_key create RSA and elliptic curve keys in the vault, respectively. If a key with the same name already exists, a new version of the key is created.

from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.keys.aio import KeyClient

credential = DefaultAzureCredential()
key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)

# Create an RSA key
rsa_key = await key_client.create_rsa_key("rsa-key-name", size=2048)
print(rsa_key.name)
print(rsa_key.key_type)

# Create an elliptic curve key
ec_key = await key_client.create_ec_key("ec-key-name", curve="P-256")
print(ec_key.name)
print(ec_key.key_type)

Asynchronously list keys

list_properties_of_keys lists the properties of all of the keys in the client's vault.

from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.keys.aio import KeyClient

credential = DefaultAzureCredential()
key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
keys = key_client.list_properties_of_keys()

async for key in keys:
    print(key.name)

Troubleshooting

See the azure-keyvault-keys troubleshooting guide for details on how to diagnose various failure scenarios.

General

Key Vault clients raise exceptions defined in azure-core. For example, if you try to get a key that doesn't exist in the vault, KeyClient raises ResourceNotFoundError:

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient
from azure.core.exceptions import ResourceNotFoundError

credential = DefaultAzureCredential()
key_client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)

try:
    key_client.get_key("which-does-not-exist")
except ResourceNotFoundError as e:
    print(e.message)

Logging

This library uses the standard logging library for logging. Basic information about HTTP sessions (URLs, headers, etc.) is logged at INFO level.

Detailed DEBUG level logging, including request/response bodies and unredacted headers, can be enabled on a client with the logging_enable argument:

from azure.identity import DefaultAzureCredential
from azure.keyvault.keys import KeyClient
import sys
import logging

# Create a logger for the 'azure' SDK
logger = logging.getLogger('azure')
logger.setLevel(logging.DEBUG)

# Configure a console output
handler = logging.StreamHandler(stream=sys.stdout)
logger.addHandler(handler)

credential = DefaultAzureCredential()

# This client will log detailed information about its HTTP sessions, at DEBUG level
client = KeyClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential, logging_enable=True)

Similarly, logging_enable can enable detailed logging for a single operation, even when it isn't enabled for the client:

client.get_key("my-key", logging_enable=True)

Next steps

Several samples are available in the Azure SDK for Python GitHub repository. These provide example code for additional Key Vault scenarios:

Additional documentation

For more extensive documentation on Azure Key Vault, see the API reference documentation.

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution. For details, visit https://cla.microsoft.com.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information, see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.

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