(mvc/fieldtype) add immutable UniqueIdField, @fraenki just add UniqueIdField...

(mvc/fieldtype) add immutable UniqueIdField, @fraenki just add UniqueIdField to your model and this one will autogenerate new unique identifiers for you

(cherry picked from commit 8c35f297)

src/opnsense/mvc/app/models/OPNsense/Base/FieldTypes/UniqueIdField.php

+<?php
+/**
+ *    Copyright (C) 2016 Deciso B.V.
+ *
+ *    All rights reserved.
+ *
+ *    Redistribution and use in source and binary forms, with or without
+ *    modification, are permitted provided that the following conditions are met:
+ *
+ *    1. Redistributions of source code must retain the above copyright notice,
+ *       this list of conditions and the following disclaimer.
+ *
+ *    2. Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *
+ *    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ *    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ *    AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ *    AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+ *    OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ *    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ *    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ *    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ *    POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+namespace OPNsense\Base\FieldTypes;
+
+use Phalcon\Validation\Validator\InclusionIn;
+
+/**
+ * Class UniqueIdField
+ * @package OPNsense\Base\FieldTypes
+ */
+class UniqueIdField extends BaseField
+{
+    /**
+     * @var bool marks if this is a data node or a container
+     */
+    protected $internalIsContainer = false;
+
+    /**
+     * @var string default validation message string
+     */
+    protected $internalValidationMessage = "Unique ID is immutable";
+
+    /**
+     * @var null|string initial field value
+     */
+    private $initialValue = null;
+
+    /**
+     * generate unique id (if none available) and store previous value for comparison before save
+     */
+    public function eventPostLoading()
+    {
+        if (empty($this->internalValue)) {
+            $this->internalValue = uniqid('', true);
+        }
+        $this->initialValue = $this->internalValue;
+    }
+
+    /**
+     * retrieve field validators for this field type
+     * @return array
+     */
+    public function getValidators()
+    {
+        $validators = parent::getValidators();
+        // unique id may not change..
+        $validators[] = new InclusionIn(array('message' => $this->internalValidationMessage,
+            'domain'=>array($this->initialValue)));
+        return $validators;
+    }
+}