Getting access_token for Azure Managed Identity in Azure DataFactory as text?

Introduction

Azure Data Factory (ADF) is a cloud-based data integration service that allows you to create, schedule and manage data pipelines. It supports various data sources and destinations such as Azure Blob Storage, Azure SQL Database, and more. ADF also allows you to use Azure Managed Identities, which provides an automatic and secure way to authenticate with Azure services without requiring explicit credentials.

In this article, we will demonstrate how to get an access token for an Azure Managed Identity in Azure Data Factory as text using Azure PowerShell.

Prerequisites

Before we start, make sure you have the following prerequisites:

• An Azure subscription.
• Azure PowerShell module installed. You can install it by running the following command in PowerShell:

powershellCopy code

Install-Module -Name Az -AllowClobber

• A Managed Identity created for your Azure Data Factory. You can create a Managed Identity by going to your Data Factory in the Azure portal, selecting “Identity” from the left-hand menu, and then clicking “System Assigned”.

Getting the Access Token

To get the access token for an Azure Managed Identity in Azure Data Factory as text, you can use the Azure PowerShell module to make a request to the Azure Instance Metadata Service (IMDS) endpoint. Here’s how you can do it:

1. Open a PowerShell console and connect to your Azure account:

Connect-AzAccount

1. Get the access token for the Managed Identity using the Invoke-WebRequest cmdlet to make a request to the IMDS endpoint:

$accessToken = (Invoke-WebRequest -Uri "http://169.254.169.254/metadata/identity/oauth2/token?api-version=2018-02-01&resource=https://management.azure.com/" -Headers @{Metadata="true"} -Method GET).Content | ConvertFrom-Json | Select-Object -ExpandProperty access_token

1. This command sends a GET request to the IMDS endpoint, which returns an access token for the Managed Identity. The ConvertFrom-Json cmdlet is used to convert the JSON response to an object, and Select-Object -ExpandProperty access_token is used to select the access token as a string.
2. The $accessToken variable now contains the access token as a string. You can use this token in your Azure Data Factory pipeline or activity.

Conclusion

In this article, we demonstrated how to get an access token for an Azure Managed Identity in Azure Data Factory as text using Azure PowerShell. By using a Managed Identity, you can avoid having to manage explicit credentials, which can improve security and simplify your authentication process.