From df76e5785f87d9113ca1802a2f8c948c6acb686e Mon Sep 17 00:00:00 2001
From: Brent Shaffer <bshafs@gmail.com>
Date: Thu, 26 Aug 2021 10:53:47 -0700
Subject: [PATCH 1/3] feat: add retryable

---
 src/Middleware/RetryMiddleware.php | 94 ++++++++++++++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 src/Middleware/RetryMiddleware.php

diff --git a/src/Middleware/RetryMiddleware.php b/src/Middleware/RetryMiddleware.php
new file mode 100644
index 0000000000..03fcefe754
--- /dev/null
+++ b/src/Middleware/RetryMiddleware.php
@@ -0,0 +1,94 @@
+<?php
+/*
+ * Copyright 2021 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace Google\Auth\Middleware;
+
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+/**
+ * RetryMiddleware is a Guzzle Middleware that allows for retrying certain error
+ * codes automatically.
+ *
+ * Requests are accessed using the Simple API access developer key.
+ */
+class RetryMiddleware
+{
+    private $retryAttempts;
+
+    /**
+     * Creates a new RetryMiddleware.
+     *
+     * @param array $config {
+     *     Configuration array
+     *
+     *     @type int $retryAttempts number of retry attempts.
+     * }
+     */
+    public function __construct($config = [])
+    {
+        $config = ['retryAttempts' => 1] + $config;
+        $this->retryAttempts = $config['retryAttempts'];
+    }
+
+    /**
+     * Retry the response if it has retryable error codes.
+     *
+     *   use Google\Auth\Middleware\AuthTokenMiddleware;
+     *   use Google\Auth\Middleware\RetryMiddleware;
+     *   use Google\Auth\OAuth2;
+     *   use GuzzleHttp\Client;
+     *   use GuzzleHttp\HandlerStack;
+     *
+     *   $config = [..<oauth config param>.];
+     *   $oauth2 = new OAuth2($config)
+     *   $authMiddleware = new AuthTokenMiddleware($oauth2);
+     *   $retryMiddleware = new RetryMiddleware($retryAttempts = 3);
+     *   $stack = HandlerStack::create();
+     *   $stack->push($authMiddleware);
+     *   $stack->push($retryMiddleware);
+     *
+     *   $client = new Client([
+     *       'handler' => $stack,
+     *       'base_uri' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+     *       'auth' => 'google_auth' // authorize all requests
+     *   ]);
+     *
+     *   $res = $client->get('myproject/taskqueues/myqueue');
+     *
+     * @param callable $handler
+     * @return \Closure
+     */
+    public function __invoke(callable $handler)
+    {
+        return function (RequestInterface $request, array $options) use ($handler) {
+            $response = $handler($request, $options);
+            for ($attempts = 0; $attempts < $this->retryAttempts; $attempts++) {
+                if ($this->isRetryable($response)) {
+                    $response = $handler($request, $options);
+                }
+            }
+            return $response;
+        };
+    }
+
+    private function isRetryable(ResponseInterface $response)
+    {
+        // no-op for now, this is a Proof of Concept!
+        return false;
+    }
+}

From 7b43a39a6a12fd9dbb7bbadf1dd006402ac66da4 Mon Sep 17 00:00:00 2001
From: Brent Shaffer <bshafs@gmail.com>
Date: Thu, 26 Aug 2021 11:11:42 -0700
Subject: [PATCH 2/3] require retryAttemps to be set

---
 src/Middleware/RetryMiddleware.php | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/Middleware/RetryMiddleware.php b/src/Middleware/RetryMiddleware.php
index 03fcefe754..9f289653ac 100644
--- a/src/Middleware/RetryMiddleware.php
+++ b/src/Middleware/RetryMiddleware.php
@@ -41,7 +41,10 @@ class RetryMiddleware
      */
     public function __construct($config = [])
     {
-        $config = ['retryAttempts' => 1] + $config;
+        if (!isset($config['retryAttempts'])) {
+            throw new \InvalidArgumentException('requires retryAttempts to be set');
+        }
+
         $this->retryAttempts = $config['retryAttempts'];
     }
 
@@ -57,7 +60,7 @@ public function __construct($config = [])
      *   $config = [..<oauth config param>.];
      *   $oauth2 = new OAuth2($config)
      *   $authMiddleware = new AuthTokenMiddleware($oauth2);
-     *   $retryMiddleware = new RetryMiddleware($retryAttempts = 3);
+     *   $retryMiddleware = new RetryMiddleware(['retryAttempts' => 3]);
      *   $stack = HandlerStack::create();
      *   $stack->push($authMiddleware);
      *   $stack->push($retryMiddleware);

From cbf1748f0c0d8aa12c57927dd794b41bffc597a2 Mon Sep 17 00:00:00 2001
From: Brent Shaffer <betterbrent@google.com>
Date: Thu, 26 Aug 2021 11:36:27 -0700
Subject: [PATCH 3/3] Update RetryMiddleware.php

---
 src/Middleware/RetryMiddleware.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Middleware/RetryMiddleware.php b/src/Middleware/RetryMiddleware.php
index 9f289653ac..86b7091ece 100644
--- a/src/Middleware/RetryMiddleware.php
+++ b/src/Middleware/RetryMiddleware.php
@@ -39,7 +39,7 @@ class RetryMiddleware
      *     @type int $retryAttempts number of retry attempts.
      * }
      */
-    public function __construct($config = [])
+    public function __construct(array $config = [])
     {
         if (!isset($config['retryAttempts'])) {
             throw new \InvalidArgumentException('requires retryAttempts to be set');