introducing db external connection

README.md

@@ -344,7 +344,13 @@ $telegram->enableMySQL($mysql_credentials, $BOT_NAME . '_');
 
 Consider to use the *utf8mb4* branch if you find some special characters problems.
 You can also store inline query and chosen inline query in the database.
+#### External Database connection
+Is possible to provide to the library an external mysql connection. Here's how to configure it:
 
+```php
+$telegram->enableExternalMySQL($external_pdo_connection)
+//$telegram->enableExternalMySQL($external_pdo_connection, $table_prefix)
+```
 ### Channels Support
 
 All methods implemented can be used to manage channels.

src/DB.php

@@ -74,47 +74,81 @@ class DB
             throw new TelegramException('MySQL credentials not provided!');
         }
 
-        self::$telegram = $telegram;
-        self::$mysql_credentials = $credentials;
-        self::$table_prefix = $table_prefix;
         $dsn = 'mysql:host=' . $credentials['host'] . ';dbname=' . $credentials['database'];
         $options = [\PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8'];
         try {
             $pdo = new \PDO($dsn, $credentials['user'], $credentials['password'], $options);
             $pdo->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_WARNING);
+        } catch (\PDOException $e) {
+            throw new TelegramException($e->getMessage());
+        }
 
-            //Define table
-            if (!defined('TB_TELEGRAM_UPDATE')) {
-                define('TB_TELEGRAM_UPDATE', self::$table_prefix.'telegram_update');
-            }
-            if (!defined('TB_MESSAGE')) {
-                define('TB_MESSAGE', self::$table_prefix.'message');
-            }
-            if (!defined('TB_INLINE_QUERY')) {
-                define('TB_INLINE_QUERY', self::$table_prefix.'inline_query');
-            }
+        self::$pdo = $pdo;
+        self::$telegram = $telegram;
+        self::$mysql_credentials = $credentials;
+        self::$table_prefix = $table_prefix;
 
-            if (!defined('TB_CHOSEN_INLINE_QUERY')) {
-                define('TB_CHOSEN_INLINE_QUERY', self::$table_prefix.'chosen_inline_query');
-            }
-            if (!defined('TB_USER')) {
-                define('TB_USER', self::$table_prefix.'user');
-            }
-            if (!defined('TB_CHAT')) {
-                define('TB_CHAT', self::$table_prefix.'chat');
-            }
-            if (!defined('TB_USER_CHAT')) {
-                define('TB_USER_CHAT', self::$table_prefix.'user_chat');
-            }
+        self::defineTable();
 
-        } catch (\PDOException $e) {
-            throw new TelegramException($e->getMessage());
+        return self::$pdo;
+    }
+
+    /**
+     * External Initialize
+     *
+     * Let you use the class with an external already existing Pdo Mysql connection.
+     *
+     * @param PDO      $external_pdo_connection PDO database object
+     * @param Telegram $telegram                Telegram object to connect with this object
+     * @param string   $table_prefix            Table prefix
+     *
+     * @return PDO PDO database object
+     */
+    public static function externalInitialize($external_pdo_connection, Telegram $telegram, $table_prefix = null)
+    {
+        if (empty($external_pdo_connection)) {
+            throw new TelegramException('MySQL external connection not provided!');
         }
 
         self::$pdo = $pdo;
+        self::$telegram = $telegram;
+        self::$mysql_credentials = null;
+        self::$table_prefix = $table_prefix;
+
+        self::defineTable();
+
         return self::$pdo;
     }
 
+    /**
+     * Define all the table with the proper prefix
+     */
+    protected static function defineTable()
+    {
+        if (!defined('TB_TELEGRAM_UPDATE')) {
+            define('TB_TELEGRAM_UPDATE', self::$table_prefix.'telegram_update');
+        }
+        if (!defined('TB_MESSAGE')) {
+            define('TB_MESSAGE', self::$table_prefix.'message');
+        }
+        if (!defined('TB_INLINE_QUERY')) {
+            define('TB_INLINE_QUERY', self::$table_prefix.'inline_query');
+        }
+
+        if (!defined('TB_CHOSEN_INLINE_QUERY')) {
+            define('TB_CHOSEN_INLINE_QUERY', self::$table_prefix.'chosen_inline_query');
+        }
+        if (!defined('TB_USER')) {
+            define('TB_USER', self::$table_prefix.'user');
+        }
+        if (!defined('TB_CHAT')) {
+            define('TB_CHAT', self::$table_prefix.'chat');
+        }
+        if (!defined('TB_USER_CHAT')) {
+            define('TB_USER_CHAT', self::$table_prefix.'user_chat');
+        }
+    }
+
     /**
      * Check if database connection has been created
      *

src/Telegram.php

@@ -176,9 +176,9 @@ class Telegram
     }
 
     /**
-     * Initialize
+     * Initialize Database connection
      *
-     * @param array $credential
+     * @param array  $credential
      * @param string $table_prefix
      */
     public function enableMySQL(array $credential, $table_prefix = null)
@@ -187,6 +187,18 @@ class Telegram
         $this->mysql_enabled = true;
     }
 
+    /**
+     * Initialize Database external connection
+     *
+     * @param PDO    $external_pdo_connection PDO database object
+     * @param string $table_prefix
+     */
+    public function enableExternalMySQL($external_pdo_connection, $table_prefix = null)
+    {
+        $this->pdo = DB::externalInitialize($external_pdo_connection, $this, $table_prefix);
+        $this->mysql_enabled = true;
+    }
+
     /**
      * Get commands list
      *