runff 1.0 commit

lib/aws/Aws/Crypto/MetadataEnvelope.php

@@ -0,0 +1,57 @@
+<?php
+namespace Aws\Crypto;
+
+use Aws\HasDataTrait;
+use \ArrayAccess;
+use \IteratorAggregate;
+use \InvalidArgumentException;
+use \JsonSerializable;
+
+/**
+ * Stores encryption metadata for reading and writing.
+ *
+ * @internal
+ */
+class MetadataEnvelope implements ArrayAccess, IteratorAggregate, JsonSerializable
+{
+    use HasDataTrait;
+
+    const CONTENT_KEY_V2_HEADER = 'x-amz-key-v2';
+    const IV_HEADER = 'x-amz-iv';
+    const MATERIALS_DESCRIPTION_HEADER = 'x-amz-matdesc';
+    const KEY_WRAP_ALGORITHM_HEADER = 'x-amz-wrap-alg';
+    const CONTENT_CRYPTO_SCHEME_HEADER = 'x-amz-cek-alg';
+    const CRYPTO_TAG_LENGTH_HEADER = 'x-amz-tag-len';
+    const UNENCRYPTED_CONTENT_MD5_HEADER = 'x-amz-unencrypted-content-md5';
+    const UNENCRYPTED_CONTENT_LENGTH_HEADER = 'x-amz-unencrypted-content-length';
+
+    private static $constants = [];
+
+    public static function getConstantValues()
+    {
+        if (empty(self::$constants)) {
+            $reflection = new \ReflectionClass(static::class);
+            foreach (array_values($reflection->getConstants()) as $constant) {
+                self::$constants[$constant] = true;
+            }
+        }
+
+        return array_keys(self::$constants);
+    }
+
+    public function offsetSet($name, $value)
+    {
+        $constants = self::getConstantValues();
+        if (is_null($name) || !in_array($name, $constants)) {
+            throw new InvalidArgumentException('MetadataEnvelope fields must'
+                . ' must match a predefined offset; use the header constants.');
+        }
+
+        $this->data[$name] = $value;
+    }
+
+    public function jsonSerialize()
+    {
+        return $this->data;
+    }
+}