Make sure we vary on the Authorization header

composer.json

@@ -24,17 +24,20 @@
         "php-http/discovery": "^1.0",
         "php-http/client-implementation": "^1.0",
         "php-http/client-common": "^1.3",
-        "php-http/cache-plugin": "^1.3"
+        "php-http/cache-plugin": "^1.4"
     },
     "require-dev": {
         "phpunit/phpunit": "^4.0 || ^5.5",
         "php-http/guzzle6-adapter": "^1.0",
         "guzzlehttp/psr7": "^1.2",
-        "sllh/php-cs-fixer-styleci-bridge": "^1.3"
+        "sllh/php-cs-fixer-styleci-bridge": "^1.3",
+        "cache/array-adapter": "^0.5.0"
     },
     "autoload": {
         "psr-4": { "Github\\": "lib/Github/" }
     },
+    "minimum-stability": "dev",
+    "prefer-stable": true,
     "extra": {
         "branch-alias": {
             "dev-master": "2.3.x-dev"

lib/Github/HttpClient/Builder.php

@@ -13,6 +13,7 @@
 use Http\Message\RequestFactory;
 use Http\Message\StreamFactory;
 use Psr\Cache\CacheItemPoolInterface;
+use Http\Client\Common\Plugin\Cache\Generator\HeaderCacheKeyGenerator;
 
 /**
  * A builder that builds the API client.
@@ -181,6 +182,9 @@ public function addHeaderValue($header, $headerValue)
      */
     public function addCache(CacheItemPoolInterface $cachePool, array $config = [])
     {
+        if (!isset($config['cache_key_generator'])) {
+            $config['cache_key_generator'] = new HeaderCacheKeyGenerator(['Authorization', 'Cookie', 'Accept', 'Content-type']);
+        }
         $this->cachePlugin = Plugin\CachePlugin::clientCache($cachePool, $this->streamFactory, $config);
         $this->httpClientModified = true;
     }

test/Github/Tests/Functional/CacheTest.php

@@ -0,0 +1,69 @@
+<?php
+
+namespace Github\Tests\Functional;
+
+use Cache\Adapter\PHPArray\ArrayCachePool;
+use Github\Client;
+use GuzzleHttp\Psr7\Response;
+use function GuzzleHttp\Psr7\stream_for;
+
+/**
+ * @group functional
+ *
+ * @author Tobias Nyholm <[email protected]>
+ */
+class CacheTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @test
+     */
+    public function shouldServeCachedResponse()
+    {
+        $mockClient = new \Http\Mock\Client();
+        $mockClient->addResponse($this->getCurrentUserResponse('nyholm'));
+        $mockClient->addResponse($this->getCurrentUserResponse('octocat'));
+
+        $github = Client::createWithHttpClient($mockClient);
+        $github->addCache(new ArrayCachePool(), ['default_ttl'=>600]);
+
+        $github->authenticate('fake_token_aaa', Client::AUTH_HTTP_TOKEN);
+        $userA = $github->currentUser()->show();
+        $this->assertEquals('nyholm', $userA['login']);
+
+        $userB = $github->currentUser()->show();
+        $this->assertEquals('nyholm', $userB['login'], 'Two request following each other should be cached.');
+    }
+    /**
+     * @test
+     */
+    public function shouldVaryOnAuthorization()
+    {
+        $mockClient = new \Http\Mock\Client();
+        $mockClient->addResponse($this->getCurrentUserResponse('nyholm'));
+        $mockClient->addResponse($this->getCurrentUserResponse('octocat'));
+
+        $github = Client::createWithHttpClient($mockClient);
+        $github->addCache(new ArrayCachePool(), ['default_ttl'=>600]);
+
+        $github->authenticate('fake_token_aaa', Client::AUTH_HTTP_TOKEN);
+        $userA = $github->currentUser()->show();
+        $this->assertEquals('nyholm', $userA['login']);
+
+        $github->authenticate('fake_token_bbb', Client::AUTH_HTTP_TOKEN);
+        $userB = $github->currentUser()->show();
+        $this->assertEquals('octocat', $userB['login'], 'We must vary on the Authorization header.');
+    }
+
+    private function getCurrentUserResponse($username)
+    {
+        $headers = [
+            'Content-Type' => 'application/json',
+        ];
+
+        $body = stream_for(json_encode([
+          'login' => $username,
+        ]));
+
+        return new Response(200, $headers, $body);
+    }
+}