Azure Identity client library for Python¶
The Azure Identity library provides Azure Active Directory (AAD) token authentication through a set of convenient TokenCredential implementations. It enables Azure SDK clients to authenticate with AAD, while also allowing other Python apps to authenticate with AAD work and school accounts, Microsoft personal accounts (MSA), and other Identity providers like AAD B2C service.
Source code | Package (PyPI) | API reference documentation | Azure Active Directory documentation
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
Getting started¶
Prerequisites¶
Python 3.6 or a recent version of Python 3 (this library doesn’t support end-of-life versions)
Authenticate during local development¶
When debugging and executing code locally it is typical for developers to use their own accounts for authenticating calls to Azure services. The Azure Identity library supports authenticating through developer tools to simplify local development.
Authenticate via Visual Studio Code¶
Developers using Visual Studio Code can use the Azure Account extension to authenticate via the editor. Apps using DefaultAzureCredential
or VisualStudioCodeCredential
can then use this account to authenticate calls in their app when running locally.
To authenticate in Visual Studio Code, ensure version 0.9.11 or earlier of the Azure Account extension is installed. To track progress toward supporting newer extension versions, see this GitHub issue. Once installed, open the Command Palette and run the Azure: Sign In command.
Authenticate via the Azure CLI¶
DefaultAzureCredential
and AzureCliCredential
can authenticate as the user
signed in to the Azure CLI. To sign in to the Azure CLI, run
az login
. On a system with a default web browser, the Azure CLI will launch
the browser to authenticate a user.
When no default browser is available, az login
will use the device code
authentication flow. This can also be selected manually by running az login --use-device-code
.
Key concepts¶
Credentials¶
A credential is a class which contains or can obtain the data needed for a service client to authenticate requests. Service clients across the Azure SDK accept a credential instance when they are constructed, and use that credential to authenticate requests.
The Azure Identity library focuses on OAuth authentication with Azure Active Directory (AAD). It offers a variety of credential classes capable of acquiring an AAD access token. See the Credential classes section below for a list of this library’s credential classes.
DefaultAzureCredential¶
DefaultAzureCredential
is appropriate for most applications which will run in the Azure Cloud because it combines common production credentials with development credentials. DefaultAzureCredential
attempts to authenticate via the following mechanisms in this order, stopping when one succeeds:
Environment -
DefaultAzureCredential
will read account information specified via environment variables and use it to authenticate.Managed Identity - If the application is deployed to an Azure host with Managed Identity enabled,
DefaultAzureCredential
will authenticate with it.Visual Studio Code - If a user has signed in to the Visual Studio Code Azure Account extension,
DefaultAzureCredential
will authenticate as that user.Azure CLI - If a user has signed in via the Azure CLI
az login
command,DefaultAzureCredential
will authenticate as that user.Azure PowerShell - If a user has signed in via Azure PowerShell’s
Connect-AzAccount
command,DefaultAzureCredential
will authenticate as that user.Interactive browser - If enabled,
DefaultAzureCredential
will interactively authenticate a user via the default browser. This is disabled by default.
DefaultAzureCredential
is intended to simplify getting started with the SDK by handling common scenarios with reasonable default behaviors. Developers who want more control or whose scenario isn’t served by the default settings should use other credential types.
Managed Identity¶
DefaultAzureCredential
and ManagedIdentityCredential
support
managed identity authentication
in any hosting environment which supports managed identities, such as (this list is not exhaustive):
Examples¶
The following examples are provided below:
Authenticate with DefaultAzureCredential
¶
More details on configuring your environment to use the DefaultAzureCredential
can be found in the class’s reference documentation.
This example demonstrates authenticating the BlobServiceClient
from the
azure-storage-blob library using
DefaultAzureCredential
.
from azure.identity import DefaultAzureCredential
from azure.storage.blob import BlobServiceClient
default_credential = DefaultAzureCredential()
client = BlobServiceClient(account_url, credential=default_credential)
Enable interactive authentication with DefaultAzureCredential
¶
Interactive authentication is disabled in the DefaultAzureCredential
by
default and can be enabled with a keyword argument:
DefaultAzureCredential(exclude_interactive_browser_credential=False)
When enabled, DefaultAzureCredential
falls back to interactively
authenticating via the system’s default web browser when no other credential is
available.
Specify a user assigned managed identity for DefaultAzureCredential
¶
Many Azure hosts allow the assignment of a user assigned managed identity. To
configure DefaultAzureCredential
to authenticate a user assigned identity,
use the managed_identity_client_id
keyword argument:
DefaultAzureCredential(managed_identity_client_id=client_id)
Alternatively, set the environment variable AZURE_CLIENT_ID
to the identity’s
client ID.
Define a custom authentication flow with ChainedTokenCredential
¶
DefaultAzureCredential
is generally the quickest way to get started developing
applications for Azure. For more advanced scenarios,
ChainedTokenCredential links multiple credential instances
to be tried sequentially when authenticating. It will try each chained
credential in turn until one provides a token or fails to authenticate due to
an error.
The following example demonstrates creating a credential which will attempt to
authenticate using managed identity, and fall back to authenticating via the
Azure CLI when a managed identity is unavailable. This example uses the
EventHubProducerClient
from the azure-eventhub client library.
from azure.eventhub import EventHubProducerClient
from azure.identity import AzureCliCredential, ChainedTokenCredential, ManagedIdentityCredential
managed_identity = ManagedIdentityCredential()
azure_cli = AzureCliCredential()
credential_chain = ChainedTokenCredential(managed_identity, azure_cli)
client = EventHubProducerClient(namespace, eventhub_name, credential_chain)
Async credentials¶
This library includes a set of async APIs. To use the async credentials in azure.identity.aio, you must first install an async transport, such as aiohttp. See azure-core documentation for more information.
Async credentials should be closed when they’re no longer needed. Each async
credential is an async context manager and defines an async close
method. For
example:
from azure.identity.aio import DefaultAzureCredential
# call close when the credential is no longer needed
credential = DefaultAzureCredential()
...
await credential.close()
# alternatively, use the credential as an async context manager
credential = DefaultAzureCredential()
async with credential:
...
This example demonstrates authenticating the asynchronous SecretClient
from
azure-keyvault-secrets with an asynchronous
credential.
from azure.identity.aio import DefaultAzureCredential
from azure.keyvault.secrets.aio import SecretClient
default_credential = DefaultAzureCredential()
client = SecretClient("https://my-vault.vault.azure.net", default_credential)
Cloud configuration¶
Credentials default to authenticating to the Azure Active Directory endpoint for
Azure Public Cloud. To access resources in other clouds, such as Azure Government
or a private cloud, configure credentials with the authority
argument.
AzureAuthorityHosts
defines authorities for well-known clouds:
from azure.identity import AzureAuthorityHosts
DefaultAzureCredential(authority=AzureAuthorityHosts.AZURE_GOVERNMENT)
Not all credentials require this configuration. Credentials which authenticate
through a development tool, such as AzureCliCredential
, use that tool’s
configuration. Similarly, VisualStudioCodeCredential
accepts an authority
argument but defaults to the authority matching VS Code’s “Azure: Cloud” setting.
Credential classes¶
Authenticate Azure hosted applications¶
credential |
usage |
---|---|
simplified authentication to get started developing applications for the Azure cloud |
|
define custom authentication flows composing multiple credentials |
|
authenticate a service principal or user configured by environment variables |
|
authenticate the managed identity of an Azure resource |
Authenticate service principals¶
credential |
usage |
---|---|
authenticate a service principal using a secret |
|
authenticate a service principal using a certificate |
Authenticate users¶
credential |
usage |
---|---|
interactively authenticate a user with the default web browser |
|
interactively authenticate a user on a device with limited UI |
|
authenticate a user with a username and password (does not support multi-factor authentication) |
Authenticate via development tools¶
credential |
usage |
---|---|
authenticate as the user signed in to the Azure CLI |
|
authenticate as the user signed in to the Visual Studio Code Azure Account extension |
Environment variables¶
DefaultAzureCredential and EnvironmentCredential can be configured with environment variables. Each type of authentication requires values for specific variables:
variable name |
value |
---|---|
|
id of an Azure Active Directory application |
|
id of the application’s Azure Active Directory tenant |
|
one of the application’s client secrets |
variable name |
value |
---|---|
|
id of an Azure Active Directory application |
|
id of the application’s Azure Active Directory tenant |
|
path to a PEM or PKCS12 certificate file including private key (without password protection) |
variable name |
value |
---|---|
|
id of an Azure Active Directory application |
|
a username (usually an email address) |
|
that user’s password |
Configuration is attempted in the above order. For example, if values for a client secret and certificate are both present, the client secret will be used.
Troubleshooting¶
See the troubleshooting guide for details on how to diagnose various failure scenarios.
Error handling¶
Credentials raise CredentialUnavailableError
when they’re unable to attempt
authentication because they lack required data or state. For example,
EnvironmentCredential will raise this exception when
its configuration is incomplete.
Credentials raise azure.core.exceptions.ClientAuthenticationError
when they fail
to authenticate. ClientAuthenticationError
has a message
attribute which
describes why authentication failed. When raised by
DefaultAzureCredential
or ChainedTokenCredential
,
the message collects error messages from each credential in the chain.
For more details on handling specific Azure Active Directory errors please refer to the Azure Active Directory error code documentation.
Logging¶
This library uses the standard logging library for logging. Credentials log basic information, including HTTP sessions (URLs, headers, etc.) at INFO level. These log entries do not contain authentication secrets.
Detailed DEBUG level logging, including request/response bodies and header values, is not enabled by default. It can be enabled with the logging_enable
argument, for example:
credential = DefaultAzureCredential(logging_enable=True)
CAUTION: DEBUG level logs from credentials contain sensitive information. These logs must be protected to avoid compromising account security.
Next steps¶
Client library support¶
Client and management libraries listed on the Azure SDK release page which support Azure AD authentication accept credentials from this library. You can learn more about using these libraries in their documentation, which is linked from the release page.
Known issues¶
This library doesn’t support Azure AD B2C.
For other open issues, refer to the library’s GitHub repository.
Provide feedback¶
If you encounter bugs or have suggestions, please open an issue.
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.