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) - 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

  • Vault administration (azure-keyvault-administration) - role-based access control (RBAC), and vault-level backup and restore options

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

Getting started

Install the package

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

pip install azure-keyvault-certificates azure-identity

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

Prerequisites

  • An Azure subscription

  • Python 2.7, 3.5.3, or later

  • A Key Vault. If you need to create one, you can use the Azure Cloud Shell to create one with these commands (replace "my-resource-group" and "my-key-vault" with your own, unique names):

    (Optional) if you want a new resource group to hold the Key Vault:

    az group create --name my-resource-group --location westus2
    

    Create the Key Vault:

    az keyvault create --resource-group my-resource-group --name my-key-vault
    

    Output:

    {
        "id": "...",
        "location": "westus2",
        "name": "my-key-vault",
        "properties": {
            "accessPolicies": [...],
            "createMode": null,
            "enablePurgeProtection": null,
            "enableSoftDelete": null,
            "enabledForDeployment": false,
            "enabledForDiskEncryption": null,
            "enabledForTemplateDeployment": null,
            "networkAcls": null,
            "provisioningState": "Succeeded",
            "sku": { "name": "standard" },
            "tenantId": "...",
            "vaultUri": "https://my-key-vault.vault.azure.net/"
        },
        "resourceGroup": "my-resource-group",
        "type": "Microsoft.KeyVault/vaults"
    }
    

    The "vaultUri" property is the vault_url used by CertificateClient

Authenticate the client

This document demonstrates using DefaultAzureCredential to authenticate as a service principal. However, CertificateClient accepts any azure-identity credential. See the azure-identity documentation for more information about other credentials.

Create a service principal (optional)

This Azure Cloud Shell snippet shows how to create a new service principal. Before using it, replace “your-application-name” with a more appropriate name for your service principal.

Create a service principal:

az ad sp create-for-rbac --name http://my-application --skip-assignment

Output:

{
    "appId": "generated app id",
    "displayName": "my-application",
    "name": "http://my-application",
    "password": "random password",
    "tenant": "tenant id"
}

Use the output to set AZURE_CLIENT_ID (“appId” above), AZURE_CLIENT_SECRET (“password” above) and AZURE_TENANT_ID (“tenant” above) environment variables. The following example shows a way to do this in Bash:

export AZURE_CLIENT_ID="generated app id"
export AZURE_CLIENT_SECRET="random password"
export AZURE_TENANT_ID="tenant id"

Authorize the service principal to perform certificate operations in your Key Vault:

az keyvault set-policy --name my-key-vault --spn $AZURE_CLIENT_ID --certificate-permissions backup create delete get import list purge recover restore update

Possible certificate permissions: backup, create, delete, deleteissuers, get, getissuers, import, list, listissuers, managecontacts, manageissuers, purge, recover, restore, setissuers, update

Create a client

Once the AZURE_CLIENT_ID, AZURE_CLIENT_SECRET and AZURE_TENANT_ID environment variables are set, DefaultAzureCredential will be able to authenticate the CertificateClient.

Constructing the client also requires your vault’s URL, which you can get from the Azure CLI or the Azure Portal. In the Azure Portal, this URL is the vault’s “DNS Name”.

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)

Key concepts

Certificate Client

With a CertificateClient 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 below.

Examples

This section contains code snippets covering common tasks:

Create a Certificate

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.

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 with the name of the certificate.

Retrieve a Certificate

get_certificate retrieves the latest version of a certificate previously stored in the Key Vault.

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 retrieves a specific version of a certificate.

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 updates a certificate previously stored in the Key Vault.

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 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 enabled, and you want to purge (permanently delete) the certificate as soon as possible. When soft-delete is disabled, begin_delete_certificate itself is permanent.

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 lists the properties of all certificates in the specified Key Vault.

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 async API supported on Python 3.5+. To use it, you must first install an async transport, such as aiohttp. See azure-core documentation for more information.

Async clients should be closed when they’re no longer needed. Each async client is an async context manager and defines an async close method. For example:

from azure.keyvault.certificates import CertificateClient

# call close when the client is no longer needed
client = CertificateClient()
...
await client.close()

# alternatively, use the client as an async context manager
client = CertificateClient()
async with client:
  ...

Asynchronously create a Certificate

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 if it is not.

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 lists all the properties of the certificates in the client’s vault:

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

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, CertificateClient raises ResourceNotFoundError:

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 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.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:

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:

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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