
sipo1 (sipo1) asked a question.
I have created a Slack App, but I am a little bit confused with the Profile Mappings. As far as I know, I just need to set the OKTA -> Slack mappings. I wonder under what circumstances do I need to set the Slack -> OKTA mappings.
BTW, if I created an IdP, under what circumstances do I need to set the OKTA -> IdP mappings.

Hi @sipo1 (sipo1) , Thank you for reaching out to the Okta Community!
These options are available for all apps to cover possible requirements and use cases. For some apps, attribute write-back is required. For example Huma Resources Management apps would be the ones managing the user's profile in Okta.
It's not mandatory to configure that in your case if you're planning to manage your users in Okta and then push the data to Slack.
Hope this clarifies things!
Thanks for your reply. But how to write-back the attribute, by OKTA open api or some standard protocol? Are there any specific apps need this configuration so that I can try it?
The attribute write-back would be indeed performed via API, the specific app's API (depending on the app, it could be SCIM).
As for an example, Google Workspace (G Suite) could work. You could for example attempt to manage the "phone number" attribute for your users by making it sourced in Okta and the rest of the profile would be sourced on the Google side.
So you would go about setting up a regular implementation of the Google app. Under Provisioning→ To Okta you would enabled the "Profile & Lifecycle Sourcing" feature.
Then under the Okta Admin Dashboard→ Profile Editor you would configure the "phone" attribute specifically as being sourced by Okta instead of Google.
Here are some resources to help you get started:
Generic information about Attribute Sourcing:
https://help.okta.com/en/prod/Content/Topics/users-groups-profiles/usgp-about-attribute-sourcing.htm
Attribute sourcing:
https://help.okta.com/en/prod/Content/Topics/users-groups-profiles/usgp-define-attribute-profile-source.htm
Google Workspace Provisioning:
https://help.okta.com/en/prod/Content/Topics/Provisioning/Google/google-provisioning.htm