From e7e8a8b554ef0c3e2267155db01bf85d611c5779 Mon Sep 17 00:00:00 2001
From: Daniel Alm <Daniel.Alm@ForumD.net>
Date: Fri, 23 Apr 2021 18:16:01 +0200
Subject: [PATCH] feat: Allow RequestWrapperTrait to use its auth cache when
 fetching ADC (#3959)

* feat: Allow RequestWrapperTrait to use the its auth cache when fetching ADC

* Avoid nested `FetchAuthTokenCache`s.

* Use instanceof instead of is_a

Co-authored-by: Brent Shaffer <betterbrent@google.com>

* Update RequestWrapperTrait.php

Co-authored-by: Brent Shaffer <betterbrent@google.com>
---
 src/RequestWrapperTrait.php | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/src/RequestWrapperTrait.php b/src/RequestWrapperTrait.php
index 65aa189..887f26e 100644
--- a/src/RequestWrapperTrait.php
+++ b/src/RequestWrapperTrait.php
@@ -178,11 +178,17 @@ public function getCredentialsFetcher()
             }
         }
 
-        return new FetchAuthTokenCache(
-            $fetcher,
-            $this->authCacheOptions,
-            $this->authCache
-        );
+        if ($fetcher instanceof FetchAuthTokenCache) {
+            // The fetcher has already been wrapped in a cache by `ApplicationDefaultCredentials`;
+            // no need to wrap it another time.
+            return $fetcher;
+        } else {
+            return new FetchAuthTokenCache(
+                $fetcher,
+                $this->authCacheOptions,
+                $this->authCache
+            );
+        }
     }
 
     /**
@@ -196,8 +202,8 @@ protected function getADC()
         return ApplicationDefaultCredentials::getCredentials(
             $this->scopes,
             $this->authHttpHandler,
-            null,
-            null,
+            $this->authCacheOptions,
+            $this->authCache,
             $this->quotaProject
         );
     }