Allow to update the teams scheme to default scheme (#8855)

api4/team.go

@@ -842,7 +842,7 @@ func updateTeamScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	schemeID := model.SchemeIDFromJson(r.Body)
-	if schemeID == nil || len(*schemeID) != 26 {
+	if schemeID == nil || (len(*schemeID) != 26 && *schemeID != "") {
 		c.SetInvalidParam("scheme_id")
 		return
 	}
@@ -857,15 +857,17 @@ func updateTeamScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	scheme, err := c.App.GetScheme(*schemeID)
-	if err != nil {
-		c.Err = err
-		return
-	}
+	if *schemeID != "" {
+		scheme, err := c.App.GetScheme(*schemeID)
+		if err != nil {
+			c.Err = err
+			return
+		}
 
-	if scheme.Scope != model.SCHEME_SCOPE_TEAM {
-		c.Err = model.NewAppError("Api4.UpdateTeamScheme", "api.team.update_team_scheme.scheme_scope.error", nil, "", http.StatusBadRequest)
-		return
+		if scheme.Scope != model.SCHEME_SCOPE_TEAM {
+			c.Err = model.NewAppError("Api4.UpdateTeamScheme", "api.team.update_team_scheme.scheme_scope.error", nil, "", http.StatusBadRequest)
+			return
+		}
 	}
 
 	team, err := c.App.GetTeam(c.Params.TeamId)
@@ -874,7 +876,7 @@ func updateTeamScheme(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	team.SchemeId = &scheme.Id
+	team.SchemeId = schemeID
 
 	_, err = c.App.UpdateTeamScheme(team)
 	if err != nil {

api4/team_test.go

@@ -2095,6 +2095,10 @@ func TestUpdateTeamScheme(t *testing.T) {
 	_, resp := th.SystemAdminClient.UpdateTeamScheme(team.Id, teamScheme.Id)
 	CheckNoError(t, resp)
 
+	// Test the return to default scheme
+	_, resp = th.SystemAdminClient.UpdateTeamScheme(team.Id, "")
+	CheckNoError(t, resp)
+
 	// Test various invalid team and scheme id combinations.
 	_, resp = th.SystemAdminClient.UpdateTeamScheme(team.Id, "x")
 	CheckBadRequestStatus(t, resp)