Switch to signing decorator

Signed-off-by: Kim Pepper <[email protected]>

src/OpenSearch/Aws/SigningClientDecorator.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace OpenSearch\Aws;
+
+use Aws\Credentials\CredentialsInterface;
+use Aws\Signature\SignatureInterface;
+use Psr\Http\Client\ClientInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+/**
+ * A decorator client that signs requests using the provided AWS credentials and signer.
+ */
+class SigningClientDecorator implements ClientInterface
+{
+    public function __construct(
+        protected ClientInterface $inner,
+        protected CredentialsInterface $credentials,
+        protected SignatureInterface $signer,
+    ) {
+        if (!class_exists(SignatureInterface::class)) {
+            throw new \RuntimeException(
+                'The AWS SDK for PHP must be installed in order to use the AWS signing client.'
+            );
+        }
+    }
+
+    public function sendRequest(RequestInterface $request): ResponseInterface
+    {
+        $request = $request->withHeader('x-amz-content-sha256', hash('sha256', (string) $request->getBody()));
+        $request = $this->signer->signRequest($request, $this->credentials);
+        return $this->inner->sendRequest($request);
+    }
+}

util/template/namespace-property

@@ -1 +1,4 @@
-    protected :namespaceNamespace $:var_namespace;
+    /**
+     * @var :namespaceNamespace
+     */
+    protected $:var_namespace;