Merge 9a283d8 into 73cd015

composer.json

@@ -36,14 +36,16 @@
         "psr/container": "^1.0",
         "sandrokeil/interop-config": "^2.0.1",
         "prooph/bookdown-template": "^0.2.3",
-        "malukenho/docheader": "^0.1.4"
+        "malukenho/docheader": "^0.1.4",
+        "psr/simple-cache": "^1.0"
     },
     "suggest": {
         "react/promise": "^2.4.1 for usage with provided QueryBus",
         "prooph/event-store-bus-bridge": "Let the EventBus dispatch persisted DomainEvents",
         "zendframework/zend-servicemanager": "Use Zend ServiceManager to lazy load your handlers and listeners",
         "prooph/service-bus-zfc-rbac-bridge": "Use ZfcRbac as authorization service for route and finalize guard",
         "psr/container": "^1.0 for usage of provided factories",
+        "psr/simple-cache": "^1.0 for usage of provided CachePlugin",
         "sandrokeil/interop-config": "For usage of provided factories"
     },
     "conflict": {

src/Plugin/CacheKeyGenerator.php

@@ -0,0 +1,20 @@
+<?php
+/**
+ * This file is part of the prooph/service-bus.
+ * (c) 2014-2018 prooph software GmbH <contact@prooph.de>
+ * (c) 2015-2018 Sascha-Oliver Prolic <saschaprolic@googlemail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Prooph\ServiceBus\Plugin;
+
+use Prooph\Common\Messaging\Query;
+
+interface CacheKeyGenerator
+{
+    public function getCacheKey(Query $query): string;
+}

src/Plugin/CacheKeyGenerator/Standard.php

@@ -0,0 +1,30 @@
+<?php
+/**
+ * This file is part of the prooph/service-bus.
+ * (c) 2014-2018 prooph software GmbH <contact@prooph.de>
+ * (c) 2015-2018 Sascha-Oliver Prolic <saschaprolic@googlemail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Prooph\ServiceBus\Plugin\CacheKeyGenerator;
+
+use Prooph\Common\Messaging\Query;
+use Prooph\ServiceBus\Plugin\CacheKeyGenerator;
+
+final class Standard implements CacheKeyGenerator
+{
+    public function getCacheKey(Query $query): string
+    {
+        $keyParts = [$query->messageName()];
+        foreach ($query->payload() as $key => $value) {
+            $keyParts[] = $key;
+            $keyParts[] = $value;
+        }
+
+        return sha1(json_encode($keyParts));
+    }
+}

src/Plugin/CachePlugin.php

@@ -0,0 +1,68 @@
+<?php
+/**
+ * This file is part of the prooph/service-bus.
+ * (c) 2014-2018 prooph software GmbH <contact@prooph.de>
+ * (c) 2015-2018 Sascha-Oliver Prolic <saschaprolic@googlemail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Prooph\ServiceBus\Plugin;
+
+use Prooph\Common\Event\ActionEvent;
+use Prooph\ServiceBus\MessageBus;
+use Prooph\ServiceBus\QueryBus;
+use Psr\SimpleCache\CacheInterface;
+
+final class CachePlugin extends AbstractPlugin
+{
+    private $cache;
+    private $keyGenerator;
+
+    public function __construct(
+        CacheInterface $cache,
+        CacheKeyGenerator $keyGenerator = null
+    ) {
+        $this->cache = $cache;
+        $this->keyGenerator = $keyGenerator ?: new CacheKeyGenerator\Standard();
+    }
+
+    public function attachToMessageBus(MessageBus $messageBus): void
+    {
+        if (! $messageBus instanceof QueryBus) {
+            throw new \InvalidArgumentException(sprintf(
+                'The cache plugin can only be attached to an instance of "Prooph\ServiceBus\QueryBus", got "%s".',
+                get_class($messageBus)
+            ));
+        }
+
+        $this->listenerHandlers[] = $messageBus->attach(
+            QueryBus::EVENT_DISPATCH,
+            function (ActionEvent $actionEvent): void {
+                if ($actionEvent->getParam(MessageBus::EVENT_PARAM_MESSAGE_HANDLED, false)) {
+                    return;
+                }
+
+                $query = $actionEvent->getParam(QueryBus::EVENT_PARAM_MESSAGE);
+
+                $deferred = $actionEvent->getParam(QueryBus::EVENT_PARAM_DEFERRED);
+
+                $key = $this->keyGenerator->getCacheKey($query);
+                if (null !== $result = $this->cache->get($key)) {
+                    $deferred->resolve($result);
+                    $actionEvent->setParam(MessageBus::EVENT_PARAM_MESSAGE_HANDLER, null);
+
+                    return;
+                }
+
+                $deferred->promise()->then(function ($data) use ($key) {
+                    $this->cache->set($key, $data);
+                });
+            },
+            QueryBus::PRIORITY_INVOKE_HANDLER + 1
+        );
+    }
+}

tests/Plugin/CachePluginTest.php

@@ -0,0 +1,119 @@
+<?php
+/**
+ * This file is part of the prooph/service-bus.
+ * (c) 2014-2018 prooph software GmbH <contact@prooph.de>
+ * (c) 2015-2018 Sascha-Oliver Prolic <saschaprolic@googlemail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ProophTest\ServiceBus\Plugin;
+
+use PHPUnit\Framework\TestCase;
+use Prooph\Common\Messaging\Query;
+use Prooph\ServiceBus\CommandBus;
+use Prooph\ServiceBus\EventBus;
+use Prooph\ServiceBus\Plugin\CacheKeyGenerator;
+use Prooph\ServiceBus\Plugin\CachePlugin;
+use Prooph\ServiceBus\Plugin\Plugin;
+use Prooph\ServiceBus\Plugin\Router\QueryRouter;
+use Prooph\ServiceBus\QueryBus;
+use Psr\SimpleCache\CacheInterface;
+use React\Promise\Deferred;
+
+class CachePluginTest extends TestCase
+{
+    private $cache;
+    private $keyGen;
+    private $plugin;
+
+    public function setUp()
+    {
+        $this->cache = $this->prophesize(CacheInterface::class);
+        $this->keyGen = $this->prophesize(CacheKeyGenerator::class);
+        $this->plugin = new CachePlugin(
+            $this->cache->reveal(),
+            $this->keyGen->reveal()
+        );
+    }
+
+    /**
+     * @test
+     */
+    public function it_is_a_message_bus_plugin()
+    {
+        $this->assertInstanceOf(Plugin::class, $this->plugin);
+    }
+
+    /**
+     * @test
+     */
+    public function it_resolves_with_cached_value_on_hit()
+    {
+        $queryBus = new QueryBus();
+
+        $router = new QueryRouter();
+        $router->route('a-query')
+           ->to(function ($query, Deferred $deferred): void {
+           });
+        $router->attachToMessageBus($queryBus);
+        $query = $this->prophesize(Query::class);
+        $this->plugin->attachToMessageBus($queryBus);
+
+        $query->messageName()->willReturn('a-query');
+        $this->keyGen->getCacheKey($query)->willReturn('cache-key');
+        $this->cache->get('cache-key')->willReturn('Hello World');
+
+        $promise = $queryBus->dispatch($query->reveal());
+        $value = null;
+        $promise->then(function ($result) use (&$value) {
+            $value = $result;
+        });
+        $this->assertEquals('Hello World', $value);
+    }
+
+    /**
+     * @test
+     */
+    public function it_caches_resolved_value()
+    {
+        $queryBus = new QueryBus();
+
+        $router = new QueryRouter();
+        $router->route('a-query')
+            ->to(function ($query, Deferred $deferred): void {
+                $deferred->resolve('Hello World');
+            });
+        $router->attachToMessageBus($queryBus);
+        $query = $this->prophesize(Query::class);
+        $this->plugin->attachToMessageBus($queryBus);
+
+        $query->messageName()->willReturn('a-query');
+        $this->keyGen->getCacheKey($query)->willReturn('cache-key');
+        $this->cache->get('cache-key')->willReturn(null);
+        $this->cache->set('cache-key', 'Hello World')->shouldBeCalled();
+
+        $queryBus->dispatch($query->reveal());
+    }
+
+    /**
+     * @test
+     */
+    public function it_does_not_attach_to_command_bus()
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        $this->plugin->attachToMessageBus(new CommandBus());
+    }
+
+    /**
+     * @test
+     */
+    public function it_does_not_attach_to_event_bus()
+    {
+        $this->expectException(\InvalidArgumentException::class);
+        $this->plugin->attachToMessageBus(new EventBus());
+    }
+}