Tutorial: Use Azure Key Vault with a virtual machine in Python

Azure Key Vault helps you to protect keys, secrets, and certificates, such as API keys and database connection strings.

In this tutorial, you set up a Python application to read information from Azure Key Vault by using managed identities for Azure resources. You learn how to:

Before you begin, read Key Vault basic concepts.

If you don't have an Azure subscription, create a trial subscription.

Prerequisites

For Windows, Mac, and Linux:

• Git
• This tutorial requires that you run the Azure CLI locally. You must have the Azure CLI version 2.0.4 or later installed. Run az --version to find the version. If you need to install or upgrade the CLI, see Install Azure CLI 2.0.

Log in to Azure

To log in to Azure by using the Azure CLI, enter:

az cloud set -n AzureChinaCloud
az login
# az cloud set -n AzureCloud   //means return to Public Azure.

Create a resource group and key vault

This quickstart uses a precreated Azure key vault. You can create a key vault by following the steps in the Azure CLI quickstart, Azure PowerShell quickstart, or Azure portal quickstart.

Alternatively, you can run these Azure CLI or Azure PowerShell commands.

az group create --name "myResourceGroup" -l "ChinaEast"

az keyvault create --name "<your-unique-keyvault-name>" -g "myResourceGroup" --enable-rbac-authorization

New-AzResourceGroup -Name myResourceGroup -Location chinaeast

New-AzKeyVault -Name <your-unique-keyvault-name> -ResourceGroupName myResourceGroup -Location chinaeast

Populate your key vault with a secret

Let's create a secret called mySecret, with a value of Success!. A secret might be a password, a SQL connection string, or any other information that you need to keep both secure and available to your application.

To add a secret to your newly created key vault, use the following command:

az keyvault secret set --vault-name "<your-unique-keyvault-name>" --name "mySecret" --value "Success!"

$secret = ConvertTo-SecureString -String 'Success!' -AsPlainText
Set-AzKeyVaultSecret -VaultName <your-unique-keyvault-name> -Name mySecret -SecretValue $secret

Create a virtual machine

Create a VM called myVM using one of the following methods:

To create a Linux VM using the Azure CLI, use the az vm create command. The following example adds a user account named azureuser. The --generate-ssh-keys parameter is used to automatically generate an SSH key, and put it in the default key location (~/.ssh).

az vm create \
  --resource-group myResourceGroup \
  --name myVM \
  --image Ubuntu2204 \
  --admin-username azureuser \
  --generate-ssh-keys

Note the value of publicIpAddress in the output.

Assign an identity to the VM

Create a system-assigned identity for the virtual machine by using the Azure CLI az vm identity assign command:

az vm identity assign --name "myVM" --resource-group "myResourceGroup"

Note the system-assigned identity that's displayed in the following code. The output of the preceding command would be:

{
  "systemAssignedIdentity": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
  "userAssignedIdentities": {}
}

Assign permissions to the VM identity

Now you can assign the previously created identity permissions to your key vault by running the following command:

az keyvault set-policy --name "<your-unique-keyvault-name>" --object-id "<systemAssignedIdentity>" --secret-permissions get list

Log in to the VM

To sign in to the virtual machine, follow the instructions in Connect and sign in to an Azure virtual machine running Linux or Connect and sign in to an Azure virtual machine running Windows.

To log into a Linux VM, you can use the ssh command with the <publicIpAddress> given in the Create a virtual machine step:

ssh azureuser@<PublicIpAddress>

Install Python libraries on the VM

On the virtual machine, install the two Python libraries we'll be using in our Python script: azure-keyvault-secrets and azure.identity.

On a Linux VM, for instance, you can install these using pip3:

pip3 install azure-keyvault-secrets

pip3 install azure.identity

Create and edit the sample Python script

On the virtual machine, create a Python file called sample.py. Edit the file to contain the following code, replacing <your-unique-keyvault-name> with the name of your key vault:

from azure.keyvault.secrets import SecretClient
from azure.identity import DefaultAzureCredential

key_vault_name = "<your-unique-keyvault-name>"
key_vault_uri = f"https://{key_vault_name}.vault.azure.cn"
secret_name = "mySecret"

credential = DefaultAzureCredential()
client = SecretClient(vault_url=key_vault_uri, credential=credential)
retrieved_secret = client.get_secret(secret_name)

print(f"The value of secret '{secret_name}' in '{key_vault_name}' is: '{retrieved_secret.value}'")

Run the sample Python app

Lastly, run sample.py. If all has gone well, it should return the value of your secret:

python3 sample.py

The value of secret 'mySecret' in '<your-unique-keyvault-name>' is: 'Success!'

Clean up resources

When they're no longer needed, delete the virtual machine and your key vault. You can be done quickly by deleting the resource group to which they belong:

az group delete -g myResourceGroup

Next steps

Azure Key Vault REST API