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Azure Identity client library for Python - version 1.18.0b2

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The Azure Identity library provides Microsoft Entra ID (formerly Azure Active Directory) token authentication support across the Azure SDK. It provides a set of TokenCredential implementations, which can be used to construct Azure SDK clients that support Microsoft Entra token authentication.

Source code | Package (PyPI) | Package (Conda) | API reference documentation | Microsoft Entra ID documentation

Getting started

Install the package

Install Azure Identity with pip:

pip install azure-identity

Prerequisites

  • An Azure subscription
  • Python 3.8 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's 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 the Azure Account extension is installed. Once installed, open the Command Palette and run the Azure: Sign In command.

It's a known issue that VisualStudioCodeCredential doesn't work with Azure Account extension versions newer than 0.9.11. A long-term fix to this problem is in progress. In the meantime, consider authenticating via the Azure CLI.

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 flow can also be selected manually by running az login --use-device-code.

Authenticate via the Azure Developer CLI

Developers coding outside of an IDE can also use the Azure Developer CLI to authenticate. Applications using the DefaultAzureCredential or the AzureDeveloperCliCredential can then use this account to authenticate calls in their application when running locally.

To authenticate with the Azure Developer CLI, users can run the command azd auth login. For users running on a system with a default web browser, the Azure Developer CLI will launch the browser to authenticate the user.

For systems without a default web browser, the azd auth login --use-device-code command will use the device code authentication flow.

Key concepts

Credentials

A credential is a class that 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're constructed, and use that credential to authenticate requests.

The Azure Identity library focuses on OAuth authentication with Microsoft Entra ID. It offers various credential classes capable of acquiring a Microsoft Entra access token. See the Credential classes section below for a list of this library's credential classes.

DefaultAzureCredential

DefaultAzureCredential is appropriate for most applications that will run in Azure because it combines common production credentials with development credentials. DefaultAzureCredential attempts to authenticate via the following mechanisms, in this order, stopping when one succeeds:

Note: DefaultAzureCredential is intended to simplify getting started with the library 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.

DefaultAzureCredential authentication flow

  1. Environment - DefaultAzureCredential will read account information specified via environment variables and use it to authenticate.
  2. Workload Identity - If the application is deployed to Azure Kubernetes Service with Managed Identity enabled, DefaultAzureCredential will authenticate with it.
  3. Managed Identity - If the application is deployed to an Azure host with Managed Identity enabled, DefaultAzureCredential will authenticate with it.
  4. Azure CLI - If a user has signed in via the Azure CLI az login command, DefaultAzureCredential will authenticate as that user.
  5. Azure PowerShell - If a user has signed in via Azure PowerShell's Connect-AzAccount command, DefaultAzureCredential will authenticate as that user.
  6. Azure Developer CLI - If the developer has authenticated via the Azure Developer CLI azd auth login command, the DefaultAzureCredential will authenticate with that account.
  7. Interactive browser - If enabled, DefaultAzureCredential will interactively authenticate a user via the default browser. This credential type is disabled by default.

Continuation policy

As of version 1.14.0, DefaultAzureCredential will attempt to authenticate with all developer credentials until one succeeds, regardless of any errors previous developer credentials experienced. For example, a developer credential may attempt to get a token and fail, so DefaultAzureCredential will continue to the next credential in the flow. Deployed service credentials will stop the flow with a thrown exception if they're able to attempt token retrieval, but don't receive one. Prior to version 1.14.0, developer credentials would similarly stop the authentication flow if token retrieval failed, but this is no longer the case.

This allows for trying all of the developer credentials on your machine while having predictable deployed behavior.

Note about VisualStudioCodeCredential

Due to a known issue, VisualStudioCodeCredential has been removed from the DefaultAzureCredential token chain. When the issue is resolved in a future release, this change will be reverted.

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 that will first attempt to authenticate using managed identity. The credential will 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. For more information, see azure-core documentation.

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)

Managed identity support

Managed identity authentication is supported via either the DefaultAzureCredential or the ManagedIdentityCredential directly for the following Azure services:

Examples

Authenticate with a user-assigned managed identity

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

credential = ManagedIdentityCredential(client_id=managed_identity_client_id)
client = SecretClient("https://my-vault.vault.azure.net", credential)

Authenticate with a system-assigned managed identity

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

credential = ManagedIdentityCredential()
client = SecretClient("https://my-vault.vault.azure.net", credential)

Cloud configuration

Credentials default to authenticating to the Microsoft Entra 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)

If the authority for your cloud isn't listed in AzureAuthorityHosts, you can explicitly specify its URL:

DefaultAzureCredential(authority="https://login.partner.microsoftonline.cn")

As an alternative to specifying the authority argument, you can also set the AZURE_AUTHORITY_HOST environment variable to the URL of your cloud's authority. This approach is useful when configuring multiple credentials to authenticate to the same cloud:

AZURE_AUTHORITY_HOST=https://login.partner.microsoftonline.cn

Not all credentials require this configuration. Credentials that 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
DefaultAzureCredential Provides a simplified authentication experience to quickly start developing applications run in Azure.
ChainedTokenCredential Allows users to define custom authentication flows composing multiple credentials.
EnvironmentCredential Authenticates a service principal or user via credential information specified in environment variables.
ManagedIdentityCredential Authenticates the managed identity of an Azure resource.
WorkloadIdentityCredential Supports Microsoft Entra Workload ID on Kubernetes.

Authenticate service principals

Credential Usage Reference
AzurePipelinesCredential Supports Microsoft Entra Workload ID on Azure Pipelines.
CertificateCredential Authenticates a service principal using a certificate. Service principal authentication
ClientAssertionCredential Authenticates a service principal using a signed client assertion.
ClientSecretCredential Authenticates a service principal using a secret. Service principal authentication

Authenticate users

Credential Usage Reference Notes
AuthorizationCodeCredential Authenticates a user with a previously obtained authorization code. OAuth2 authentication code
DeviceCodeCredential Interactively authenticates a user on devices with limited UI. Device code authentication
InteractiveBrowserCredential Interactively authenticates a user with the default system browser. OAuth2 authentication code InteractiveBrowserCredential doesn't support GitHub Codespaces. As a workaround, use DeviceCodeCredential.
OnBehalfOfCredential Propagates the delegated user identity and permissions through the request chain. On-behalf-of authentication
UsernamePasswordCredential Authenticates a user with a username and password (doesn't support multi-factor authentication). Username + password authentication

Authenticate via development tools

Credential Usage Reference
AzureCliCredential Authenticates in a development environment with the Azure CLI. Azure CLI authentication
AzureDeveloperCliCredential Authenticates in a development environment with the Azure Developer CLI. Azure Developer CLI Reference
AzurePowerShellCredential Authenticates in a development environment with the Azure PowerShell. Azure PowerShell authentication
VisualStudioCodeCredential Authenticates as the user signed in to the Visual Studio Code Azure Account extension. VS Code Azure Account extension

Environment variables

DefaultAzureCredential and EnvironmentCredential can be configured with environment variables. Each type of authentication requires values for specific variables:

Service principal with secret

Variable name Value
AZURE_CLIENT_ID ID of a Microsoft Entra application
AZURE_TENANT_ID ID of the application's Microsoft Entra tenant
AZURE_CLIENT_SECRET one of the application's client secrets

Service principal with certificate

Variable name Value Required
AZURE_CLIENT_ID ID of a Microsoft Entra application X
AZURE_TENANT_ID ID of the application's Microsoft Entra tenant X
AZURE_CLIENT_CERTIFICATE_PATH path to a PEM or PKCS12 certificate file including private key X
AZURE_CLIENT_CERTIFICATE_PASSWORD password of the certificate file, if any
AZURE_CLIENT_SEND_CERTIFICATE_CHAIN if True, the credential will send the public certificate chain in the x5c header of each token request's JWT. This is required for Subject Name/Issuer (SNI) authentication. Defaults to False. There is a known limitation that async SNI authentication is not supported.

Username and password

Variable name Value
AZURE_CLIENT_ID ID of a Microsoft Entra application
AZURE_USERNAME a username (usually an email address)
AZURE_PASSWORD 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.

Continuous Access Evaluation

As of version 1.14.0, accessing resources protected by Continuous Access Evaluation (CAE) is possible on a per-request basis. This behavior can be enabled by setting the enable_cae keyword argument to True in the credential's get_token method. CAE isn't supported for developer and managed identity credentials.

Token caching

Token caching is a feature provided by the Azure Identity library that allows apps to:

  • Cache tokens in memory (default) or on disk (opt-in).
  • Improve resilience and performance.
  • Reduce the number of requests made to Microsoft Entra ID to obtain access tokens.

The Azure Identity library offers both in-memory and persistent disk caching. For more details, see the token caching documentation.

Brokered authentication

An authentication broker is an application that runs on a user’s machine and manages the authentication handshakes and token maintenance for connected accounts. Currently, only the Windows Web Account Manager (WAM) is supported. To enable support, use the azure-identity-broker package. For details on authenticating using WAM, see the broker plugin documentation.

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 information on handling specific Microsoft Entra ID errors, see the Microsoft Entra ID 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 don't contain authentication secrets.

Detailed DEBUG level logging, including request/response bodies and header values, isn't 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 that support Microsoft Entra 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, 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'll 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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