[Db] Support initial queries execution after creating connection (#5660)

* Support initial queries execution

* Support initial queries execution

* Support initial queries execution

* initial queries documentation

Author: tadasauciunas

src/Codeception/Module/Db.php

@@ -54,6 +54,7 @@
  * * ssl_verify_server_cert - disables certificate CN verification (MySQL specific, @see http://php.net/manual/de/ref.pdo-mysql.php)
  * * ssl_cipher - list of one or more permissible ciphers to use for SSL encryption (MySQL specific, @see http://php.net/manual/de/ref.pdo-mysql.php#pdo.constants.mysql-attr-cipher)
  * * databases - include more database configs and switch between them in tests.
+ * * initial_queries - list of queries to be executed right after connection to the database has been initiated, i.e. creating the database if it does not exist or preparing the database collation
  *
  * ## Example
  *
@@ -73,6 +74,10 @@
  *              ssl_ca: '/path/to/ca-cert.pem'
  *              ssl_verify_server_cert: false
  *              ssl_cipher: 'AES256-SHA'
+ *              initial_queries:
+ *                  - 'CREATE DATABASE IF NOT EXISTS temp_db;'
+ *                  - 'USE temp_db;'
+ *                  - 'SET NAMES utf8;'
  *
  * ## Example with multi-dumps
  *     modules:
@@ -559,6 +564,12 @@ private function connect($databaseKey, $databaseConfig)
             $this->_getDriver()->setWaitLock($databaseConfig['waitlock']);
         }
 
+        if (isset($databaseConfig['initial_queries'])) {
+            foreach ($databaseConfig['initial_queries'] as $initialQuery) {
+                $this->drivers[$databaseKey]->executeQuery($initialQuery, []);
+            }
+        }
+
         $this->debugSection('Db', 'Connected to ' . $databaseKey . ' ' . $this->drivers[$databaseKey]->getDb());
         $this->dbhs[$databaseKey] = $this->drivers[$databaseKey]->getDbh();
     }

tests/unit/Codeception/Module/Db/MySqlDbTest.php

@@ -64,6 +64,21 @@ public function testConnectionIsResetOnEveryTestWhenReconnectIsTrue()
         $this->assertNotEquals($connection3, $connection2);
     }
 
+    public function testInitialQueriesAreExecuted()
+    {
+        $dbName = 'test_db';
+        $config = $this->module->_getConfig();
+        $config['initial_queries'] = [
+            'CREATE DATABASE IF NOT EXISTS ' . $dbName . ';',
+            'USE ' . $dbName . ';',
+        ];
+        $this->module->_reconfigure($config);
+        $this->module->_before(\Codeception\Util\Stub::makeEmpty('\Codeception\TestInterface'));
+        $usedDatabaseName = $this->module->dbh->query('SELECT DATABASE();')->fetch(PDO::FETCH_COLUMN);
+
+        $this->assertEquals($dbName, $usedDatabaseName);
+    }
+
     public function testGrabColumnFromDatabase()
     {
         $emails = $this->module->grabColumnFromDatabase('users', 'email');