We recommend you to use service accounts as GCP credentials to ALM. To create a service account, please follow the steps below:
Go to "Service accounts" menu under "IAM & admin" section of Google Cloud Platform's main menu. Click "CREATE SERVICE ACCOUNT" button.
Give it a name and make sure the following permissions are added:
Deployment Manager Editor
Make sure to check "Furnish a new private key" with JSON as option. You will be prompted to download and save the file. Save it to a safe location.
Now go to ALM's "General Settings" menu and go "Setup Credentials". Select GCP and fill up the required fields. Under "Service Account" field, copy and paste all the contents of the Service Account JSON file you created from the previous steps.