MM-27688-OpenId Connect (#16222)

* implement openid connect

* update error strings

* handle OpenIdSetting.Secret as FAKE SETTING

* add openid to telemetry

* update config defaults, add telemetry

* fix bug with Office365

* Retrieve Office365 AuthData from IdToken

* fix linter

* add feature flag, reset defaults for config

* fix build error

* fix unit tests

* add authentication permission to Feature
Flags

* turn off feature flag

* set default button color

* set default button color only on openid

* fix for merging FeatureFlags in config

* remove feature flag

* revert config changes

* remove debug statements

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/user.go

@@ -335,19 +335,22 @@ func (a *App) createUser(user *model.User) (*model.User, *model.AppError) {
 	return ruser, nil
 }
 
-func (a *App) CreateOAuthUser(service string, userData io.Reader, teamId string) (*model.User, *model.AppError) {
+func (a *App) CreateOAuthUser(service string, userData io.Reader, teamId string, tokenUser *model.User) (*model.User, *model.AppError) {
 	if !*a.Config().TeamSettings.EnableUserCreation {
 		return nil, model.NewAppError("CreateOAuthUser", "api.user.create_user.disabled.app_error", nil, "", http.StatusNotImplemented)
 	}
 
-	provider := einterfaces.GetOauthProvider(service)
-	if provider == nil {
-		return nil, model.NewAppError("CreateOAuthUser", "api.user.create_oauth_user.not_available.app_error", map[string]interface{}{"Service": strings.Title(service)}, "", http.StatusNotImplemented)
+	provider, e := a.getSSOProvider(service)
+	if e != nil {
+		return nil, e
 	}
-	user, err1 := provider.GetUserFromJson(userData)
+	user, err1 := provider.GetUserFromJson(userData, tokenUser)
 	if err1 != nil {
 		return nil, model.NewAppError("CreateOAuthUser", "api.user.create_oauth_user.create.app_error", map[string]interface{}{"Service": service}, err1.Error(), http.StatusInternalServerError)
 	}
+	if user.AuthService == "" {
+		user.AuthService = service
+	}
 
 	suchan := make(chan store.StoreResult, 1)
 	euchan := make(chan store.StoreResult, 1)
@@ -1990,8 +1993,8 @@ func (a *App) AutocompleteUsersInTeam(teamId string, term string, options *model
 	return autocomplete, nil
 }
 
-func (a *App) UpdateOAuthUserAttrs(userData io.Reader, user *model.User, provider einterfaces.OauthProvider, service string) *model.AppError {
-	oauthUser, err1 := provider.GetUserFromJson(userData)
+func (a *App) UpdateOAuthUserAttrs(userData io.Reader, user *model.User, provider einterfaces.OauthProvider, service string, tokenUser *model.User) *model.AppError {
+	oauthUser, err1 := provider.GetUserFromJson(userData, tokenUser)
 	if err1 != nil {
 		return model.NewAppError("UpdateOAuthUserAttrs", "api.user.update_oauth_user_attrs.get_user.app_error", map[string]interface{}{"Service": service}, err1.Error(), http.StatusBadRequest)
 	}