add getConnectionUrl() with interface

src/MysqlPersistentConnection.php

@@ -16,7 +16,7 @@
  * When PHP exists or crashes, the bash script will notice and
  * remove the database(s).
  */
-class MysqlPersistentConnection implements ConnectionInterface
+class MysqlPersistentConnection implements ConnectionInterface, UrlConnectionInterface
 {
     /**
      * Bash script taking care of daemon start,
@@ -97,4 +97,30 @@ public function getConnectionParams()
     {
         return $this->connection_params;
     }
+
+    /**
+     * {@inheritdoc}
+     * @return string
+     */
+    public function getConnectionUrl(): string
+    {
+        if (array_key_exists('unix_socket', $this->connection_params)) {
+            return sprintf(
+                'mysql://%s@localhost/%s?unix_socket=%s&server_version=%s',
+                $this->connection_params['user'] ?? get_current_user(),
+                $this->connection_params['dbname'] ?? 'test',
+                $this->connection_params['unix_socket'],
+                $this->connection_params['server_version'] ?? '5.6'
+            );
+        }
+
+        return sprintf(
+            'mysql://%s@%s:%s/%s?server_version=%s',
+            $this->connection_params['user'] ?? get_current_user(),
+            $this->connection_params['hostname'] ?? 'localhost',
+            $this->connection_params['port'] ?? 3306,
+            $this->connection_params['dbname'] ?? 'test',
+            $this->connection_params['server_version'] ?? '5.6'
+        );
+    }
 }

src/UrlConnectionInterface.php

@@ -0,0 +1,28 @@
+<?php
+/**
+ * @copyright 2016-2017 Hostnet B.V.
+ */
+declare(strict_types=1);
+
+namespace Hostnet\Component\DatabaseTest;
+
+/**
+ * A connection will make sure a (new) test database
+ * will exist after construction and will clean up
+ * after destruction.
+ *
+ * The connection url for the database is
+ * provided through the getConnectionUrl method.
+ */
+interface UrlConnectionInterface
+{
+    /**
+     * Doctrine compatible database connection parameters,
+     * those could be fed directly into a new Doctrine
+     * or Symfony/Doctrine configuration file.
+     *
+     * @Example mysql://db_user:db_password@127.0.0.1:3306/db_name?server_version=5.6
+     *          mysql://db_user@localhost/db_name?unix_socket=/tmp/socket&server_version=5.6
+     */
+    public function getConnectionUrl(): string;
+}

test/MysqlPersistentConnectionTest.php

@@ -19,6 +19,10 @@ public function testConstruction()
         $connection = new MysqlPersistentConnection();
         $params     = $connection->getConnectionParams();
         $this->assertCount(1, $this->listDatabases($params));
+
+        $connection = new MysqlPersistentConnection();
+        $url        = $connection->getConnectionUrl();
+        $this->assertCount(1, $this->listDatabases(['url' => $url]));
     }
 
     /**