Azure Blob Event

Owned by Ashhad Alam
Last updated: Apr 26, 2023 by Shruti Pasayat
3 min read

An Event enables you to specify when and how frequently a Process Flow bound with it would be executed based on the polling frequency. It also overrides the parameters you have provided in the application source used in the Process Flow as an activity.

This page discusses the event having application type as Azure Blob.

You can create an Event using Azure Blob as a Source and use it in a Process Flow. Follow the steps given below to create an Azure Blob Event.

  1. Click Configure > EVENTS > Application.

  2. Click Create Application Event.

  3. On Create Application Event screen, do the followings:

    1. In the Name field, enter a name for the event.

    2. In the Description field, enter a description for the event.

    3. In the Application field, select Azure Blob as the type of application source.

    4. In the Account field, select the Azure Blob account that you want to use as a source.
      You can also create an Azure Blob account by clicking the  icon, and then providing the following information on the Create New Account screen.

      Field Name

      Description

      Provide a name for this account. e.g. "MyAccount"

      A short, descriptive name that helps you re-use this account in future.

      Access Type

      This field governs the type of authentication you choose to connect to your Azure Blob.

      Note: You can select Azure AD, Shared Key, or Shared Access Signatures as the Access Type. Based on your selection, the next field will ask you for the required input (Id, Key, or Signature) to proceed. For example, if you select Azure AD as the Access Type, the next field in the form will be Tenant Id where you’d need to enter the Tenant Id of your Azure Blob account.

      You can also use HashiCorp Vault to fetch the Shared Key and Shared Access Signatures secrets.

      • Before you use HashiCorp Vault, ensure that you have cleared the browser cache. 
      • If you ever change the secrets for this activity in HashiCorp Vault, ensure that you have cleared the cached secrets to bring the change into effect.

      Each secret is maintained as a key-value pair in Hashicorp Vault. Enter the variable in the following format in the field for which you want to fetch the secret from Vault:

       ${Vault:<Key1>}

      Where, <Key1> is the key in Hashicorp Vault that is defined for the field for which you want to fetch the secrets. 

      For example, you need to enter ${Vault:SharedAccess.Signatures} in the Shared Access Signatures field, if you have defined SharedAccess.Signatures as the key for this field in the Vault.


      For more details refer to this page.

      You can also enter the values manually.


      You can select one of the following Access Types:

      1. Azure AD– This option facilitates OAuth based authentication and the user experience will be the same as the other OAuth apps.
        Once you select Azure AD as Access Type, you’ll require the Tenant Id to enter in the next field. To know how to get the Tenant Id refer to this page in the Microsoft Azure documentation.
        After clicking Continue, the user would need to enter the Azure credentials in a new window.
      2. Shared Key – Facilitates non-OAuth based authentication. To know how to get the Shared Key, refer to this page in the Microsoft Azure documentation.
        As you complete all the fields and click Continue, your account will be created and saved.
        You may want to test if you’d be able to connect this account with Azure Blob by clicking Test.
      3. Shared Access Signatures– Facilitates non-OAuth based authentication. To know how to get the Shared Access Signature, refer to this page in the Microsoft Azure documentation.
        As you complete all the fields and click Continue, your account will be created and saved.
        You may want to test if you’d be able to connect this account with Azure Blob by clicking Test.

      Storage Account Name

      Name of your storage account in Azure.

      Container Name

      Name of the container in the selected Storage Account.

      Select Project

      Name of your Project in which you want to create a Template/Transaction.

      Once you have provided the information, click  to save the account.

    5. In the Trigger field, select either of the following triggers based on your requirement.

      Sl. no.

      Trigger

      Description

      1

      Get New Or Updated Blob

      The New or Updated Blob operation downloads the newly created or updated blob.

      2

      Get All Blob

      The Get All Blob operation downloads all blobs.

    6. In the Folder field, specify the path of the folder where the source file/blob is located.

    7. In the Search Criteria field, specify additional filter criteria in case you want to retrieve only specific type of files/blobs which matches this filter criteria. For example, *.txt. 

    8. Select Run Initial Load check box, if you want to process all the files when the event gets triggered for the first time.

    9. In the Polling Frequency field, provide the time interval at which the Process Flow bounded with it will get executed. 

    10. In the Stable Time field, provide a wait time for the file to become stable. 

      Event waits for the provided time before getting fired.

    11. Expand Advanced properties.
    12. In the Select Project field, select the project.

    13. Click Save.

Important

When this Event triggers the Process Flow, the size of the fetched Blob is captured by the fileSize context variable. You can use this variable in the Process Flow based on your requirement, for example, abort the Process Flow if the fetched Blob size is greater than 2GB.