feat: #11067 prevent removing last grafana admin permissions

pkg/services/sqlstore/user.go

@@ -504,8 +504,18 @@ func UpdateUserPermissions(cmd *m.UpdateUserPermissionsCommand) error {
 
 		user.IsAdmin = cmd.IsGrafanaAdmin
 		sess.UseBool("is_admin")
+
 		_, err := sess.ID(user.Id).Update(&user)
-		return err
+		if err != nil {
+			return err
+		}
+
+		// validate that after update there is at least one server admin
+		if err := validateOneAdminLeft(sess); err != nil {
+			return err
+		}
+
+		return nil
 	})
 }
 
@@ -522,3 +532,17 @@ func SetUserHelpFlag(cmd *m.SetUserHelpFlagCommand) error {
 		return err
 	})
 }
+
+func validateOneAdminLeft(sess *DBSession) error {
+	// validate that there is an admin user left
+	count, err := sess.Where("is_admin=?", true).Count(&m.User{})
+	if err != nil {
+		return err
+	}
+
+	if count == 0 {
+		return m.ErrLastGrafanaAdmin
+	}
+
+	return nil
+}

pkg/services/sqlstore/user_test.go

@@ -155,6 +155,32 @@ func TestUserDataAccess(t *testing.T) {
 				})
 			})
 		})
+
+		Convey("Given one grafana admin user", func() {
+			var err error
+			createUserCmd := &m.CreateUserCommand{
+				Email:   fmt.Sprint("admin", "@test.com"),
+				Name:    fmt.Sprint("admin"),
+				Login:   fmt.Sprint("admin"),
+				IsAdmin: true,
+			}
+			err = CreateUser(context.Background(), createUserCmd)
+			So(err, ShouldBeNil)
+
+			Convey("Cannot make themselves a non-admin", func() {
+				updateUserPermsCmd := m.UpdateUserPermissionsCommand{IsGrafanaAdmin: false, UserId: 1}
+				updatePermsError := UpdateUserPermissions(&updateUserPermsCmd)
+
+				So(updatePermsError, ShouldEqual, m.ErrLastGrafanaAdmin)
+
+				query := m.GetUserByIdQuery{Id: createUserCmd.Result.Id}
+				getUserError := GetUserById(&query)
+
+				So(getUserError, ShouldBeNil)
+
+				So(query.Result.IsAdmin, ShouldEqual, true)
+			})
+		})
 	})
 }