added base64 validation

Author: AlexAlexandru

src/Validation/Base64Validation.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Josegonzalez\Upload\Validation;
+
+use Josegonzalez\Upload\Validation\Traits\Base64ValidationTrait;
+
+class Base64Validation
+{
+    use Base64ValidationTrait;
+}

src/Validation/DefaultValidation.php

@@ -2,11 +2,13 @@
 
 namespace Josegonzalez\Upload\Validation;
 
+use Josegonzalez\Upload\Validation\Traits\Base64ValidationTrait;
 use Josegonzalez\Upload\Validation\Traits\ImageValidationTrait;
 use Josegonzalez\Upload\Validation\Traits\UploadValidationTrait;
 
 class DefaultValidation
 {
     use ImageValidationTrait;
     use UploadValidationTrait;
+    use Base64ValidationTrait;
 }

src/Validation/Traits/Base64ValidationTrait.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace Josegonzalez\Upload\Validation\Traits;
+
+trait Base64ValidationTrait {
+
+    /**
+     * Allows only the specified mime type to be upload when using base64 uploader
+     *
+     * @param mixed $check Value to check
+     * @param string $allowedMimeType Allowed mime type
+     * @return bool Success
+     */
+    public static function isMimeType($check, $allowedMimeType)
+    {
+        $f = finfo_open();
+        $mimeType = finfo_buffer($f, base64_decode($check), FILEINFO_MIME_TYPE);
+        return $mimeType === $allowedMimeType;
+    }
+}

tests/TestCase/Validation/Base64ValidationTest.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Josegonzalez\Upload\Test\TestCase\Validation;
+
+
+use Cake\TestSuite\TestCase;
+use Josegonzalez\Upload\Validation\Base64Validation;
+
+class Base64ValidationTest extends TestCase
+{
+
+    public function teardown()
+    {
+        parent::tearDown();
+    }
+
+    public function testIsMimeTypeOK() {
+        $png = 'iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAYAAACNiR0NAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAA7DAAAOwwHHb6hkAAAAB3RJTUUH4AMUECwX5I9GIwAAACFJREFUOMtj/P//PwM1ARMDlcGogaMGjho4auCogUPFQABpCwMlgqgSYAAAAABJRU5ErkJggg==';
+        $this->assertTrue(Base64Validation::isMimeType($png, 'image/png'));
+    }
+
+    public function testIsMimeTypeInvalid() {
+        $phpCode = 'PD9waHAgZWNobyAnQ2FrZVBocCc7ID8+';
+        $this->assertFalse(Base64Validation::isMimeType($phpCode, 'image/png'));
+    }
+}