The KEDA Documentation
KEDA Concepts
Operate
Scalers
Authentication Providers

Azure Blob Storage Click here for latest

Scale applications based on the count of blobs in a given Azure Blob Storage container.

Availability: v1.1+ Maintainer: Microsoft
Scaler code

Suggest a change

Warning

You are currently viewing v"2.1" of the documentation and it is not the latest. For the most recent documentation, kindly click here.

Notice

As of now, this Azure Blob Storage scaler scales based on the count of the blobs in a container as opposed to the Azure Functions behavior where code is only triggered on new blobs.

Trigger Specification

This specification describes the azure-blob trigger for Azure Blob Storage. It scales based on the count of blobs in a given blob storage container and assumes the worker is responsible for clearing the container by deleting/moving the blobs once the blob processing completed.

triggers:
- type: azure-blob
  metadata:
    blobContainerName: functions-blob
    blobCount: '5'
    connectionFromEnv: STORAGE_CONNECTIONSTRING_ENV_NAME
    accountName: storage-account-name
    blobPrefix: myprefix
    blobDelimiter: /example

Parameter list:

  • blobContainerName - Name of container in an Azure Storage account.
  • blobCount - Average target value to trigger scaling actions. (Default: 5, Optional)
  • connectionFromEnv - Name of the environment variable your deployment uses to get the connection string.
  • accountName - Name of the storage account that the container belongs to.
  • blobPrefix - Prefix for the Blob. Use this to specify sub path for the blobs if required. (Default: "", Optional)
  • blobDelimiter - Delimiter for identifying the blob prefix. (Default: /, Optional)

Authentication Parameters

You can authenticate by using pod identity or connection string authentication.

Connection String Authentication:

  • connection - Connection string for Azure Storage Account.

Pod Identity Authentication

  • accountName - Name of the Azure Storage Account.

Example 

apiVersion: keda.sh/v1alpha1
kind: TriggerAuthentication
metadata:
  name: azure-blob-auth
spec:
  podIdentity:
    provider: azure
---
apiVersion: keda.sh/v1alpha1
kind: ScaledObject
metadata:
  name: azure-blob-scaledobject
  namespace: default
spec:
  scaleTargetRef:
    name: azureblob-function
  triggers:
  - type: azure-blob
    metadata:
      # Required
      blobContainerName: functionsblob
      # Optional, required when pod identity is used
      accountName: storage-account-name
      # Optional, connection OR authenticationRef that defines the connection
      connectionFromEnv: STORAGE_CONNECTIONSTRING_ENV_NAME # Reference to a connection string in deployment
      # or authenticationRef as defined below
      #
      # Optional
      blobCount: "5" # default 5
      blobPrefix: blobsubpath # Default : ""
      blobDelimiter: "/" # Default: "/"
    authenticationRef:
        name: azure-blob-auth # authenticationRef would need either podIdentity or define a connection parameter