# Azure Key Vault Certificates client library for Python
Azure Key Vault helps solve the following problems:
- Certificate management (this library) - create, manage, and deploy public and private SSL/TLS certificates
- Cryptographic key management
([azure-keyvault-keys](https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-keys)) - create, store, and control access to the keys used to encrypt your data
- Secrets management
([azure-keyvault-secrets](https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-secrets)) -
securely store and control access to tokens, passwords, certificates, API keys,
and other secrets
- Vault administration ([azure-keyvault-administration](https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-administration)) - role-based access control (RBAC), and vault-level backup and restore options

[Source code][library_src]
| [Package (PyPI)][pypi_package_certificates]
| [Package (Conda)](https://anaconda.org/microsoft/azure-keyvault/)
| [API reference documentation][reference_docs]
| [Product documentation][azure_keyvault]
| [Samples][certificates_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](https://github.com/Azure/azure-sdk-for-python/wiki/Azure-SDKs-Python-version-support-policy)._

## Getting started
### Install the package
Install [azure-keyvault-certificates][pypi_package_certificates] and
[azure-identity][azure_identity_pypi] with [pip][pip]:
```Bash
pip install azure-keyvault-certificates azure-identity
```
[azure-identity][azure_identity] is used for Azure Active Directory
authentication as demonstrated below.

### Prerequisites
* An [Azure subscription][azure_sub]
* Python 3.8 or later
* An existing [Azure Key Vault][azure_keyvault]. If you need to create one, you can do so using the Azure CLI by following the steps in [this document][azure_keyvault_cli].

### Authenticate the client
In order to interact with the Azure Key Vault service, you will need an instance of a [CertificateClient][certificate_client_docs], as well as a **vault url** and a credential object. This document demonstrates using a [DefaultAzureCredential][default_cred_ref], which is appropriate for most scenarios, including local development and production environments. We recommend using a [managed identity][managed_identity] for authentication in production environments.

See [azure-identity][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][default_cred_ref] to use a suitable method of authentication, you can do the following to create a certificate client (replacing the value of `VAULT_URL` with your vault's URL):

<!-- SNIPPET:hello_world.create_a_certificate_client -->

```python
VAULT_URL = os.environ["VAULT_URL"]
credential = DefaultAzureCredential()
client = CertificateClient(vault_url=VAULT_URL, credential=credential)
```

<!-- END SNIPPET -->

> **NOTE:** For an asynchronous client, import `azure.keyvault.certificates.aio`'s `CertificateClient` instead.

## Key concepts
### CertificateClient
With a [CertificateClient][certificate_client_docs] you can get certificates from the vault, create new certificates and new versions of existing certificates, update certificate metadata, and delete certificates. You can also manage certificate issuers, contacts, and management policies of certificates. This is illustrated in the [examples](#examples) below.

## Examples
This section contains code snippets covering common tasks:
* [Create a certificate](#create-a-certificate)
* [Retrieve a certificate](#retrieve-a-certificate)
* [Update properties of an existing certificate](#update-properties-of-an-existing-certificate)
* [Delete a certificate](#delete-a-certificate)
* [List properties of certificates](#list-properties-of-certificates)
* [Async operations](#async-operations)
* [Asynchronously create a certificate](#asynchronously-create-a-certificate)
* [Asynchronously list properties of certificates](#asynchronously-list-properties-of-certificates)

### Create a certificate
[begin_create_certificate](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.begin_create_certificate)
creates a certificate to be stored in the Azure Key Vault. If a certificate with the same name already exists, a new
version of the certificate is created. Before creating a certificate, a management policy for the certificate can be
created or our default policy will be used. This method returns a long running operation poller.
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient, CertificatePolicy

credential = DefaultAzureCredential()

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

create_certificate_poller = certificate_client.begin_create_certificate(
    certificate_name="cert-name", policy=CertificatePolicy.get_default()
)
print(create_certificate_poller.result())
```
If you would like to check the status of your certificate creation, you can call `status()` on the poller or
[get_certificate_operation](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.get_certificate_operation)
with the name of the certificate.

### Retrieve a certificate
[get_certificate](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.get_certificate)
retrieves the latest version of a certificate previously stored in the Key Vault.
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient

credential = DefaultAzureCredential()

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

certificate = certificate_client.get_certificate("cert-name")

print(certificate.name)
print(certificate.properties.version)
print(certificate.policy.issuer_name)
```

[get_certificate_version](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.get_certificate_version)
retrieves a specific version of a certificate.
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient

credential = DefaultAzureCredential()

certificate_client = CertificateClient(vault_url="https://my-key-vault.vault.azure.net/", credential=credential)
certificate = certificate_client.get_certificate_version(certificate_name="cert-name", version="cert-version")

print(certificate.name)
print(certificate.properties.version)
```

### Update properties of an existing certificate
[update_certificate_properties](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.update_certificate_properties)
updates a certificate previously stored in the Key Vault.
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient

credential = DefaultAzureCredential()

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

# we will now disable the certificate for further use
updated_certificate= certificate_client.update_certificate_properties(
    certificate_name="cert-name", enabled=False
)

print(updated_certificate.name)
print(updated_certificate.properties.enabled)
```

### Delete a certificate
[begin_delete_certificate](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.begin_delete_certificate)
requests Key Vault delete a certificate, returning a poller which allows you to wait for the deletion to finish.
Waiting is helpful when the vault has [soft-delete][soft_delete] enabled, and you want to purge
(permanently delete) the certificate as soon as possible. When [soft-delete][soft_delete] is disabled,
`begin_delete_certificate` itself is permanent.

```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient

credential = DefaultAzureCredential()

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

deleted_certificate_poller = certificate_client.begin_delete_certificate("cert-name")

deleted_certificate = deleted_certificate_poller.result()
print(deleted_certificate.name)
print(deleted_certificate.deleted_on)
```
### List properties of certificates
[list_properties_of_certificates](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient.list_properties_of_certificates)
lists the properties of all certificates in the specified Key Vault.
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient

credential = DefaultAzureCredential()

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

certificates = certificate_client.list_properties_of_certificates()

for certificate in certificates:
    # this list doesn't include versions of the certificates
    print(certificate.name)
```

### Async operations
This library includes a complete set of async APIs. To use them, you must
first install an async transport, such as [aiohttp](https://pypi.org/project/aiohttp/).
See
[azure-core documentation](https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/core/azure-core/CLIENT_LIBRARY_DEVELOPER.md#transport)
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:

```python
from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.certificates.aio import CertificateClient

credential = DefaultAzureCredential()

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

### Asynchronously create a certificate
[create_certificate](https://aka.ms/azsdk/python/keyvault-certificates/aio/docs#azure.keyvault.certificates.aio.CertificateClient.create_certificate)
creates a certificate to be stored in the Azure Key Vault. If a certificate with the same name already exists, a new
version of the certificate is created. Before creating a certificate, a management policy for the certificate can be
created or our default policy will be used. Awaiting `create_certificate` returns your created certificate if creation
is successful, and a
[CertificateOperation](https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateOperation)
if it is not.
```python
from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.certificates.aio import CertificateClient
from azure.keyvault.certificates import CertificatePolicy

credential = DefaultAzureCredential()

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

create_certificate_result = await certificate_client.create_certificate(
    certificate_name="cert-name", policy=CertificatePolicy.get_default()
)
print(create_certificate_result)
```

### Asynchronously list properties of certificates
[list_properties_of_certificates](https://aka.ms/azsdk/python/keyvault-certificates/aio/docs#azure.keyvault.certificates.aio.CertificateClient.list_properties_of_certificates)
lists all the properties of the certificates in the client's vault:
```python
from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.certificates.aio import CertificateClient

credential = DefaultAzureCredential()

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

certificates = certificate_client.list_properties_of_certificates()
async for certificate in certificates:
    print(certificate.name)
```

## Troubleshooting

See the `azure-keyvault-certificates`
[troubleshooting guide](https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-certificates/TROUBLESHOOTING.md)
for details on how to diagnose various failure scenarios.

### General
Key Vault clients raise exceptions defined in [azure-core][azure_core_exceptions].
For example, if you try to get a key that doesn't exist in the vault, [CertificateClient][certificate_client_docs]
raises [ResourceNotFoundError](https://aka.ms/azsdk-python-core-exceptions-resource-not-found-error):
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient
from azure.core.exceptions import ResourceNotFoundError

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

try:
    certificate_client.get_certificate("which-does-not-exist")
except ResourceNotFoundError as e:
    print(e.message)
```
### Logging
This library uses the standard
[logging](https://docs.python.org/3.5/library/logging.html) 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:
```python
from azure.identity import DefaultAzureCredential
from azure.keyvault.certificates import CertificateClient
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 = CertificateClient(
    vault_url="https://my-key-vault.vault.azure.net/",
    credential=credential,
    logging_enable=True
)
```

Network trace logging can also be enabled for any single operation:
```python
certificate = certificate_client.get_certificate(certificate_name="cert-name", logging_enable=True)
```

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

- [Create/get/update/delete certificates][hello_world_sample] ([async version][hello_world_async_sample])
- [Back up and recover certificates][backup_operations_sample] ([async version][backup_operations_async_sample])
- [Import PKCS#12 (PFX) and PEM-formatted certificates into Key Vault][import_certificate_sample] ([async version][import_certificate_async_sample])
- [List certificates][list_operations_sample] ([async version][list_operations_async_sample])
- [Recover and purge certificates][recover_purge_operations_sample] ([async version][recover_purge_operations_async_sample])
- [Manage certificate issuers][issuers_sample] ([async version][issuers_async_sample])
- [Manage certificate contacts][contacts_sample] ([async version][contacts_async_sample])
- [Extract a certificate's private key][parse_sample] ([async version][parse_async_sample])

###  Additional documentation
For more extensive documentation on Azure Key Vault, see the [API reference documentation][reference_docs].

## 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][code_of_conduct].
For more information, see the
[Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or
contact opencode@microsoft.com with any additional questions or comments.


<!-- LINKS -->
[azure_core_exceptions]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/core/azure-core#azure-core-library-exceptions
[azure_identity]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/identity/azure-identity
[azure_identity_pypi]: https://pypi.org/project/azure-identity/
[azure_keyvault]: https://learn.microsoft.com/azure/key-vault/general/overview
[azure_keyvault_cli]: https://learn.microsoft.com/azure/key-vault/general/quick-create-cli
[azure_sub]: https://azure.microsoft.com/free/

[backup_operations_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/backup_restore_operations.py
[backup_operations_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/backup_restore_operations_async.py

[certificate_client_docs]: https://aka.ms/azsdk/python/keyvault-certificates/docs#azure.keyvault.certificates.CertificateClient
[certificates_samples]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-certificates/samples
[code_of_conduct]: https://opensource.microsoft.com/codeofconduct/
[contacts_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/contacts.py
[contacts_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/contacts_async.py

[default_cred_ref]: https://aka.ms/azsdk/python/identity/docs#azure.identity.DefaultAzureCredential

[hello_world_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/hello_world.py
[hello_world_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/hello_world_async.py

[import_certificate_sample]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-certificates/samples/import_certificate.py
[import_certificate_async_sample]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-certificates/samples/import_certificate_async.py
[issuers_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/issuers.py
[issuers_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/issuers_async.py

[library_src]: https://github.com/Azure/azure-sdk-for-python/tree/main/sdk/keyvault/azure-keyvault-certificates/azure/keyvault/certificates
[list_operations_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/list_operations.py
[list_operations_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/list_operations_async.py

[managed_identity]: https://learn.microsoft.com/azure/active-directory/managed-identities-azure-resources/overview

[parse_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/parse_certificate.py
[parse_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/parse_certificate_async.py
[pip]: https://pypi.org/project/pip/
[pypi_package_certificates]: https://pypi.org/project/azure-keyvault-certificates/

[recover_purge_operations_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/recover_purge_operations.py
[recover_purge_operations_async_sample]: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/keyvault/azure-keyvault-certificates/samples/recover_purge_operations_async.py
[reference_docs]: https://aka.ms/azsdk/python/keyvault-certificates/docs

[soft_delete]: https://learn.microsoft.com/azure/key-vault/general/soft-delete-overview