what happens when source is removed

From: grouper-users-request grouper-users-request On Behalf Of Black, Carey M.
Sent: Thursday, April 13, 2017 12:58 PM
To: grouper-users
Subject: [grouper-users] RE: Subject API "lifecycle"/"interruption of service" issue....

Any input on this?

–
Carey Matthew Black.123

From: grouper-users-request grouper-users-request On Behalf Of Black, Carey M.
Sent: Tuesday, April 11, 2017 11:14 AM
To: grouper-users
Subject: [grouper-users] Subject API "lifecycle"/"interruption of service" issue....

All,

I have stumbled into a behavior of Grouper that I think should be improved. For a several reasons. However, maybe I am not seeing some other designed way to deal with this condition.

The setup:
I added a new Subject API to grouper. However, I knew it was “temporary” as I was just “trying it out”. ( Let’s call it “TEMP”.)
I then removed the definition of the Subject API and now the Grouper UI is unable to display the memberships of any group that has any member from that TEMP Subject API.
Error message when viewing a group in the New UI:
“
Error: Cant find source with id: 'TEMP', Possible source id's: 'g:gsa', 'grouperEntities', 'grouperExternal', 'jdbc', 'g:isa', , Problem calling method viewGroup on edu.internet2.middleware.grouper.grouperUi.serviceLogic.UiV2Group
“
( And no members of the group are displayed at all. )

While I doubt it would be common to add or remove Subject APIs. I am sure this kind of event is part of “the long lifecycle” of using Grouper.

From a conceptual point, I think it would be useful for Grouper to tolerate the “failed to find” and “failed to get data” from a Subject API to allow for a transition model between Subject API sources. Basically keep the “old references” while layering in the new (replacement) references to the new Subject API. If both Subject API’s (old and new) are available, then I think life is currently good. It is when the “old” is removed that it appears to impact, at least, the functionality of the UI.

Is there a way to tell grouper to “Just use the data you have” when the subject API is undefined? ( removed subject api definition)
Is there a way to tell grouper to “Just use the data you have” when the subject API fails to return data? ( intermittent incident/outage of Subject System )
Is there a way to give grouper a “dummy subject API configuration” that would just return the data that Grouper already has for the subject API?

Is there some documentation for “How to remove a Subject API” from Grouper that I did not yet find and follow?
Are there other ideas/details about adding/removing Subject API’s that I should be aware of?

Thanks in advance.