This document explains how to delete Single Message Transforms (SMTs) from an existing Pub/Sub subscription.
To delete subscription SMTs, you can use the Google Cloud console, the Google Cloud CLI, the client library, or the Pub/Sub API.
Required roles and permissions
To get the permissions that
      you need to delete subscription SMTs,
    
      ask your administrator to grant you the Pub/Sub Editor 
( roles/pubsub.editor 
)
     IAM role on your project.
  
  
  
  
  For more information about granting roles, see Manage access to projects, folders, and organizations 
.
This predefined role contains the permissions required to delete subscription SMTs. To see the exact permissions that are required, expand the Required permissionssection:
Required permissions
The following permissions are required to delete subscription SMTs:
- Grant the delete a subscription permission on the subscription: pubsub.subscriptions.delete
- Grant the view a subscription permission on the project. This permission is only required if you are using the Google Cloud console: pubsub.subscriptions.view
You might also be able to get these permissions with custom roles or other predefined roles .
You can configure access control at the project level and at the individual resource level.
Delete subscription SMTs
To delete subscription SMTs, follow these steps:
Console
-  In the Google Cloud console, go to the Pub/Sub Subscriptionspage. 
-  Click the subscription for which you want to delete an SMT. 
-  In the subscription details page, click Edit . The Transforms tab lists all the SMTs that are attached to the subscription. 
-  Click the delete button for the SMT you would like to delete. 
-  Click Update . 
gcloud
-  In the Google Cloud console, activate Cloud Shell. At the bottom of the Google Cloud console, a Cloud Shell session starts and displays a command-line prompt. Cloud Shell is a shell environment with the Google Cloud CLI already installed and with values already set for your current project. It can take a few seconds for the session to initialize. 
-  This command deletes all SMTs associated with the specified subscription. Run the gcloud pubsub subscriptions updatecommand with the--clear-message-transformsflag:gcloud pubsub subscriptions update SUBSCRIPTION_ID \ --clear-message-transforms Replace the following: -  SUBSCRIPTION_ID : The ID or name of the subscription you want to update. 
 To instead remove a single SMT, refer to Update subscription SMTs and create a new message-transforms-filethat excludes the SMT you wish to delete.
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