My goal is to add 
The sign in documentation looks perfect as an excellent new addition for our Discourse. I’ve enabled chat integration, which is also great. A bit over my head on how to add this button as a custom option with Discourse tests-pass. Once figured out, this social login will pair nicely with similar social logins such as Github and Patreon.
Following the documentation, I’ve created an app with Oauth access in Slack… now at this step for creating button.
Slack is displaying:
App ID
Client ID
Signing Secret
Client Secret
Verification Token
Oauth Access Token
redirect url added as https://example.domain.com/slack/auth
Options I see in Discourse are:
enable sso provider
sso url – URL of single sign on endpoint (must include http:// or https://)
sso secret – Secret string used to cryptographically authenticate SSO information, be sure it is 10 characters or longer
Attempting to set up with this documentation:
Slack supports
identity.avatar - View the user’s Slack avatar
identity.basic - View information about the user’s identity
identity.email - View the user’s email address
identity.team - View the user’s Slack workspace name
It would be nice to display Slack user avatar and possibly workspace name as well. Seems that accessing their email would be useful as well since that is critically important when using discourse.