Add function for relation between user and messages

app/model/User.php

@@ -57,6 +57,16 @@ class User {
         return null;
     }
 
+    public static function getByID($user_id) {
+        $users = User::all();
+        foreach ($users as $user) {
+            if ($user->id == $user_id) {
+                return $user;
+            }
+        }
+        return null;
+    }
+
     public static function all() {
         $dbh = Database::connect();
         $stmt = $dbh->prepare("SELECT * from users");
@@ -102,5 +112,9 @@ class User {
 
         return JWT::encode($data, $key, 'HS512');
     }
+
+    public function messages() {
+        return SecureMessage::all_for($this->id);
+    }
 }
 ?>