Fix issues with binary data being stored (#188)

* Ignore binary integration tests for Void adapter

* Add common trait for armoring binary data in JSON

* Armor binary data in MongoDB adapter

* Armor binary data in encryption layer

* Update IntegrationSimpleCacheTest.php

Author: StephenClouse

JsonBinaryArmoring.php

@@ -0,0 +1,68 @@
+<?php
+
+/*
+ * This file is part of php-cache organization.
+ *
+ * (c) 2015 Aaron Scherer <[email protected]>, Tobias Nyholm <[email protected]>
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace Cache\Adapter\Common;
+
+/**
+ * This trait provides common routines for safely encoding binary and non-UTF8 data in
+ * JSON. This is needed for components that use JSON natively (currently, the MongoDB
+ * adapter and EncryptedCachePool).
+ *
+ * @author Stephen Clouse <[email protected]>
+ */
+trait JsonBinaryArmoring
+{
+    private static $ESCAPE_JSON_CHARACTERS = [
+        "\x00", "\x01", "\x02", "\x03", "\x04", "\x05", "\x06", "\x07",
+        "\x08", "\x09", "\x0A", "\x0B", "\x0C", "\x0D", "\x0E", "\x0F",
+        "\x10", "\x11", "\x12", "\x13", "\x14", "\x15", "\x16", "\x17",
+        "\x18", "\x19", "\x1A", "\x1B", "\x1C", "\x1D", "\x1E", "\x1F",
+    ];
+
+    private static $ENCODED_JSON_CHARACTERS = [
+        '\u0000', '\u0001', '\u0002', '\u0003', '\u0004', '\u0005', '\u0006', '\u0007',
+        '\u0008', '\u0009', '\u000A', '\u000B', '\u000C', '\u000D', '\u000E', '\u000F',
+        '\u0010', '\u0011', '\u0012', '\u0013', '\u0014', '\u0015', '\u0016', '\u0017',
+        '\u0018', '\u0019', '\u001A', '\u001B', '\u001C', '\u001D', '\u001E', '\u001F',
+    ];
+
+    /**
+     * Armor a value going into a JSON document.
+     *
+     * @param string $value
+     *
+     * @return string
+     */
+    protected static function jsonArmor($value)
+    {
+        return str_replace(
+            static::$ESCAPE_JSON_CHARACTERS,
+            static::$ENCODED_JSON_CHARACTERS,
+            utf8_encode($value)
+        );
+    }
+
+    /**
+     * De-armor a value from a JSON document.
+     *
+     * @param string $value
+     *
+     * @return string
+     */
+    protected static function jsonDeArmor($value)
+    {
+        return utf8_decode(str_replace(
+            static::$ENCODED_JSON_CHARACTERS,
+            static::$ESCAPE_JSON_CHARACTERS,
+            $value
+        ));
+    }
+}