add postinst doc

fix php 7.3 compatibility issues of typed properties

api/src/Database.php

@@ -6,13 +6,13 @@
  * Class with all neccessary stuff for the Database connections.
  */
 class Database {
-    private static ?Database $instance = null;
-    private mysqli $conn;
+    private static $instance = null;
+    private $conn;
 
-    private string $servername = "192.168.0.30";
-    private string $username = "root";
-    private string $password = "1qayxsw2";
-    private string $dbname = "mediacenter";
+    private $servername = "127.0.0.1";
+    private $username = "mediacenteruser";
+    private $password = "mediapassword";
+    private $dbname = "mediacenter";
 
     // The db connection is established in the private constructor.
     private function __construct() {

api/src/SSettings.php

@@ -5,7 +5,7 @@
  * class handling all Settings used by php scripts
  */
 class SSettings {
-    private ?Database $database;
+    private $database;
 
     /**
      * SSettings constructor.

api/src/handlers/RequestBase.php

@@ -2,8 +2,8 @@
 require_once 'src/Database.php';
 
 abstract class RequestBase {
-    protected mysqli $conn;
-    private array $actions = array();
+    protected $conn;
+    private $actions = array();
 
     /**
      * adds a new action handler to the current api file

api/src/handlers/Video.php

@@ -7,7 +7,7 @@ require_once 'RequestBase.php';
  * backend for all interactions with videoloads and receiving of video infos
  */
 class Video extends RequestBase {
-    private string $videopath;
+    private $videopath;
 
     public function __construct() {
         $settings = new SSettings();