Change feed support for Microsoft Azure Blob storage is now available in preview. Change feed provides a guaranteed, ordered, durable, read-only log of all the creation, modification, and deletion change events that occur to the blobs in your storage account. This log is stored as append blobs within your storage account, therefore you can manage the data retention and access control based on your requirements.

Change feed is the ideal solution for bulk handling of large volumes of blob changes in your storage account, as opposed to periodically listing and manually comparing for changes. It enables cost-efficient recording and processing by providing programmatic access such that event-driven applications can simply consume the change feed log and process change events from the last checkpoint.

Some scenarios that would benefit from consuming a blob change feed include:

Bulk processing a group of newly uploaded files for virus scanning, resizing, or backups.

Storing, auditing, and analyzing changes to your objects over any period of time for data management or compliance.

Combining data uploaded by various IoT sensors into a single collection for data transformation and insights.

Additional data movement by synchronizing with a cache, search engine, or data warehouse.

How to get started

To enroll in preview, you will need to submit a request to register this feature to your subscription. After your request is approved (within a few days), any existing or new GPv2 or blob storage accounts in West US 2 and West Central US can then enable the change feed feature.

To submit a request, run the following PowerShell or Microsoft Azure CLI commands:

Register by using PowerShell

Register-AzProviderFeature -FeatureName Changefeed -ProviderNamespace Microsoft.Storage

Register-AzResourceProvider -ProviderNamespace Microsoft.Storage

Register by using Azure CLI

az feature register --namespace Microsoft.Storage --name Changefeed

az provider register --namespace 'Microsoft.Storage'

Once you’re registered and approved for the change feed preview, you can then turn it on for your storage accounts and start consuming the log. For more information, please see change feed support in Azure Blob Storage and process change feed in Azure Blob Storage. As with most previews, this feature should not be used for production workloads until it reaches general availability.

Cost

Change feed pricing is currently in preview and subject to change for general availability. Customers are charged for the blob change events captured by change feed as well as the data storage costs of the change feed log. See block blob pricing to learn more about pricing.

Build it, use it, and tell us about it

We will continue to improve our feature capabilities and would like to hear your feedback regarding change feed or other features through email at AzureStorageFeedback@microsoft.com. As a reminder, we love hearing all of your ideas and suggestions about Azure Storage, which you can post at Azure Storage feedback forum.