Allow customer to add only specific email-addresses to Request Participants

[Chris Fortmueller]

If a customer adds Request Participants, I want to remove the new request participants which also satisfy the condition of being service desk agents

For example, assume a request has the following participants:

• 1@customer.com
• 2@customer.com
• 3@customer.com
• 1@servicedeskagent.com
• 2@servicedeskagent.com

Now a customer replies to this request via email, and adds the following emails-addresses in CC (or, alternatively, adds these via the customer portal):

• 4@customer.com
• 5@customer.com
• 3@servicedeskagent.com
• 4@servicedeskagent.com

My Service Management project is configured to allow customers to add participants this way.

I want an automation such that the resulting set of participants after the customer has made this change is:

• 1@customer.com
• 2@customer.com
• 3@customer.com
• 4@customer.com
• 5@customer.com
• 1@servicedeskagent.com
• 2@servicedeskagent.com

In other words, any emails which end in @servicedeskagent.com should not be added to the request participants. However, if these request particpants already exist for this issue, they should not be removed.

Is this possible with Automation? Maybe via some kind of Regex, possibly involving regex groups/sets?

Extra Love if there is a solution that distinguishes between whether this change came in via mail or via customer portal.