always validate schema version

app/controllers/web_migrate.php

@@ -17,8 +17,6 @@ class WebMigrateController extends StudipController
 
         parent::before_filter($action, $args);
 
-        DBSchemaVersion::validateSchemaVersion();
-
         $this->target   = Request::int('target');
         $this->branch   = Request::get('branch', '0');
         $this->version  = new DBSchemaVersion('studip', $this->branch);

cli/migrate.php

@@ -53,8 +53,6 @@ if (isset($_SERVER['argv'])) {
         }
     }
 
-    DBSchemaVersion::validateSchemaVersion();
-
     $version = new DBSchemaVersion($domain, $branch);
     $migrator = new Migrator($path, $version, $verbose);
 

lib/migrations/DBSchemaVersion.php

@@ -45,6 +45,7 @@ class DBSchemaVersion implements SchemaVersion
         $this->domain = $domain;
         $this->branch = $branch;
         $this->versions = [0];
+        $this->validateSchemaVersion();
         $this->initSchemaInfo();
     }
 
@@ -158,7 +159,7 @@ class DBSchemaVersion implements SchemaVersion
     /**
      * Validate correct structure of schema_version table.
      */
-    public static function validateSchemaVersion()
+    private function validateSchemaVersion()
     {
         $db = DBManager::get();
         $result = $db->query("SHOW TABLES LIKE 'schema_versions'");