First working docker version.

Dockerfile

@@ -3,6 +3,8 @@ FROM php:7.2-apache
 # Use the default production configuration
 RUN mv "$PHP_INI_DIR/php.ini-production" "$PHP_INI_DIR/php.ini"
 
+RUN docker-php-ext-install pdo_mysql
+
 # Enable rewrite module for httpd.
 RUN ln -s /etc/apache2/mods-available/rewrite.load /etc/apache2/mods-enabled/rewrite.load