take snapshot by event name

* If you have big events sometime it would be useful to create also a snapshot if this event occurs
prooph · Oct 17, 2016 · a8ffbff · a8ffbff
1 parent 61bd53d
commit a8ffbff
Show file tree

Hide file tree

Showing 7 changed files with 142 additions and 39 deletions.
diff --git a/.travis.yml b/.travis.yml
@@ -7,7 +7,7 @@ php:
 
 before_script:
   - composer self-update
-  - composer --dev install
+  - composer --dev install --prefer-source
 
 script:
   - php ./vendor/bin/phpunit --coverage-text --coverage-clover ./build/logs/clover.xml

diff --git a/composer.json b/composer.json
@@ -56,5 +56,14 @@
             "ProophTest\\Snapshotter\\": "tests/",
             "ProophTest\\EventStore\\": "vendor/prooph/event-store/tests/"
         }
+    },
+    "scripts": {
+        "check": [
+            "@cs",
+            "@test"
+        ],
+        "cs": "php-cs-fixer fix -v --diff --dry-run",
+        "cs-fix": "php-cs-fixer fix -v --diff",
+        "test": "phpunit"
     }
 }
diff --git a/docs/configuration.md b/docs/configuration.md
@@ -1,8 +1,9 @@
 # Configuration
 
 To enable the Snapshot-Plugin simply attach it as plugin to the event-store. 
-It needs a list of aggregate root => aggregate repositories and a version step.
-Version step 5 f.e. means take a snapshot every 5 versions.
+It needs a list of aggregate root => aggregate repositories and a version step and/or a list of event names.
+Version step 5 f.e. means take a snapshot every 5 versions. If event names provided, snaphosts also taken if one of 
+these events occurred.
 If you use the provided factories from event-store and the snapshotter, you can simply do this by configuration:
 
     return [
@@ -14,6 +15,7 @@ If you use the provided factories from event-store and the snapshotter, you can
             ],
             'snapshotter' => [
                 'version_step' => 5,
+                'event_names' => ['awesomeEvent'],
                 'aggregate_repositories' => [
                     'My\Domain\AggregateRoot' => \My\Domain\AggregateRootRepository::class,
                 ]

diff --git a/src/Container/SnapshotPluginFactory.php b/src/Container/SnapshotPluginFactory.php
@@ -36,7 +36,7 @@ public function __invoke(ContainerInterface $container)
         $config = $container->get('config');
         $config = $this->options($config);
 
-        return new SnapshotPlugin($container->get(CommandBus::class), $config['version_step']);
+        return new SnapshotPlugin($container->get(CommandBus::class), $config['version_step'], $config['event_names']);
     }
 
     /**
@@ -53,7 +53,8 @@ public function dimensions()
     public function defaultOptions()
     {
         return [
-            'version_step' => 5
+            'version_step' => 5,
+            'event_names' => [],
         ];
     }
 

diff --git a/src/SnapshotPlugin.php b/src/SnapshotPlugin.php
@@ -33,15 +33,32 @@ final class SnapshotPlugin implements Plugin
      */
     private $versionStep;
 
+    /**
+     * List of event names to take snapshot
+     *
+     * @var array
+     */
+    private $eventNames;
+
+    /**
+     * Shortcut to determine if event names available
+     *
+     * @var bool
+     */
+    private $hasEventNames;
+
     /**
      * @param CommandBus $commandBus
      * @param int $versionStep
+     * @param array $eventNames
      */
-    public function __construct(CommandBus $commandBus, $versionStep)
+    public function __construct(CommandBus $commandBus, $versionStep, array $eventNames = [])
     {
         Assertion::min($versionStep, 1);
         $this->commandBus = $commandBus;
         $this->versionStep = $versionStep;
+        $this->eventNames = $eventNames;
+        $this->hasEventNames = !empty($eventNames);
     }
 
     /**
@@ -64,12 +81,17 @@ public function onEventStoreCommitPost(ActionEvent $actionEvent)
 
         $snapshots = [];
 
+        /* @var $recordedEvent \Prooph\Common\Messaging\Message */
         foreach ($recordedEvents as $recordedEvent) {
-            if ($recordedEvent->version() % $this->versionStep !== 0) {
+            $doSnapshot = $recordedEvent->version() % $this->versionStep === 0;
+
+            if (false === $doSnapshot && false === $this->hasEventNames) {
                 continue;
             }
             $metadata = $recordedEvent->metadata();
-            if (!isset($metadata['aggregate_type']) || !isset($metadata['aggregate_id'])) {
+            if (!isset($metadata['aggregate_type'], $metadata['aggregate_id'])
+                || (false === $doSnapshot && !in_array($recordedEvent->messageName(), $this->eventNames, true))
+            ) {
                 continue;
             }
             $snapshots[$metadata['aggregate_type']][] = $metadata['aggregate_id'];

diff --git a/tests/Container/SnapshotPluginFactoryTest.php b/tests/Container/SnapshotPluginFactoryTest.php
@@ -35,12 +35,25 @@ public function it_creates_snapshot_plugin()
             'prooph' => [
                 'snapshotter' => [
                     'version_step' => 5,
-                ]
-            ]
+                    'event_names' => ['awesomeEvent'],
+                ],
+            ],
         ]);
         $container->get(CommandBus::class)->willReturn($commandBus->reveal());
 
         $factory = new SnapshotPluginFactory();
-        $this->assertInstanceOf(SnapshotPlugin::class, $factory($container->reveal()));
+        $snapshotPlugin =  $factory($container->reveal());
+
+        $this->assertInstanceOf(SnapshotPlugin::class, $snapshotPlugin);
+
+        $reflectionClass = new \ReflectionClass($snapshotPlugin);
+        $versionStepProperty = $reflectionClass->getProperty('versionStep');
+        $versionStepProperty->setAccessible(true);
+        $eventNamesProperty = $reflectionClass->getProperty('eventNames');
+        $eventNamesProperty->setAccessible(true);
+
+        $this->assertSame(5, $versionStepProperty->getValue($snapshotPlugin));
+        $this->assertArrayHasKey(0, $eventNamesProperty->getValue($snapshotPlugin));
+        $this->assertSame('awesomeEvent', $eventNamesProperty->getValue($snapshotPlugin)[0]);
     }
 }
diff --git a/tests/SnapshotPluginTest.php b/tests/SnapshotPluginTest.php
@@ -34,26 +34,36 @@
 final class SnapshotPluginTest extends TestCase
 {
     /**
-     * @test
+     * @var EventStore
      */
-    public function it_publishes_take_snapshot_commands_for_all_known_aggregates()
+    private $eventStore;
+
+    /**
+     * @var AggregateRepository
+     */
+    private $repository;
+
+    private $result;
+
+    public function setUp()
     {
         $inMemoryAdapter = new InMemoryAdapter();
         $eventEmitter    = new ProophActionEventEmitter();
 
-        $eventStore = new EventStore($inMemoryAdapter, $eventEmitter);
+        $this->eventStore = new EventStore($inMemoryAdapter, $eventEmitter);
 
-        $repository = new AggregateRepository(
-            $eventStore,
+        $this->repository = new AggregateRepository(
+            $this->eventStore,
             AggregateType::fromAggregateRootClass('ProophTest\EventStore\Mock\User'),
             new ConfigurableAggregateTranslator()
         );
 
-        $result = [];
+        $this->result = [];
+        $self = $this;
 
         $router = new CommandRouter();
-        $router->route(TakeSnapshot::class)->to(function (TakeSnapshot $command) use (&$result) {
-            $result[] = [
+        $router->route(TakeSnapshot::class)->to(function (TakeSnapshot $command) use ($self) {
+            $self->result[] = [
                 'aggregate_type' => $command->aggregateType(),
                 'aggregate_id' => $command->aggregateId()
             ];
@@ -63,33 +73,39 @@ public function it_publishes_take_snapshot_commands_for_all_known_aggregates()
         $commandBus->utilize($router);
 
         $plugin = new SnapshotPlugin($commandBus, 2);
-        $plugin->setUp($eventStore);
+        $plugin->setUp($this->eventStore);
 
-        $eventStore->beginTransaction();
+        $this->eventStore->beginTransaction();
 
-        $eventStore->create(new Stream(new StreamName('event_stream'), new \ArrayIterator()));
+        $this->eventStore->create(new Stream(new StreamName('event_stream'), new \ArrayIterator()));
 
-        $eventStore->commit();
+        $this->eventStore->commit();
+    }
 
-        $eventStore->beginTransaction();
+    /**
+     * @test
+     */
+    public function it_publishes_take_snapshot_commands_for_all_known_aggregates()
+    {
+        $this->eventStore->beginTransaction();
 
         $user = User::create('Alex', '[email protected]');
 
-        $repository->addAggregateRoot($user);
+        $this->repository->addAggregateRoot($user);
 
-        $eventStore->commit();
+        $this->eventStore->commit();
 
-        $eventStore->beginTransaction();
+        $this->eventStore->beginTransaction();
 
-        $user = $repository->getAggregateRoot($user->getId()->toString());
+        $user = $this->repository->getAggregateRoot($user->getId()->toString());
 
         $user->changeName('John');
         $user->changeName('Jane');
         $user->changeName('Jim');
 
-        $eventStore->commit();
+        $this->eventStore->commit();
 
-        $eventStore->beginTransaction();
+        $this->eventStore->beginTransaction();
 
         $eventWithoutMetadata1 = UsernameChanged::with(
             ['new_name' => 'John Doe'],
@@ -101,19 +117,59 @@ public function it_publishes_take_snapshot_commands_for_all_known_aggregates()
             6
         );
 
-        $eventStore->appendTo(new StreamName('event_stream'), new \ArrayIterator([
+        $this->eventStore->appendTo(new StreamName('event_stream'), new \ArrayIterator([
             $eventWithoutMetadata1,
             $eventWithoutMetadata2
         ]));
 
-        $eventStore->commit();
+        $this->eventStore->commit();
+
+        $this->assertCount(2, $this->result);
+        $this->assertArrayHasKey('aggregate_type', $this->result[0]);
+        $this->assertArrayHasKey('aggregate_id', $this->result[0]);
+        $this->assertArrayHasKey('aggregate_type', $this->result[1]);
+        $this->assertArrayHasKey('aggregate_id', $this->result[1]);
+        $this->assertEquals(User::class, $this->result[0]['aggregate_type']);
+        $this->assertEquals(User::class, $this->result[1]['aggregate_type']);
+    }
+
+    /**
+     * @test
+     */
+    public function it_publishes_take_snapshot_commands_by_event_name()
+    {
+        $this->eventStore->beginTransaction();
+
+        $user = User::create('Alex', '[email protected]');
+
+        $this->repository->addAggregateRoot($user);
+
+        $this->eventStore->commit();
+
+        $this->eventStore->beginTransaction();
+
+        $user = $this->repository->getAggregateRoot($user->getId()->toString());
+
+        $user->changeName('Jim');
+
+        $this->eventStore->commit();
+
+        $this->eventStore->beginTransaction();
+
+        $eventWithoutMetadata1 = UsernameChanged::with(
+            ['new_name' => 'John Doe'],
+            5
+        );
+
+        $this->eventStore->appendTo(new StreamName('event_stream'), new \ArrayIterator([
+            $eventWithoutMetadata1,
+        ]));
+
+        $this->eventStore->commit();
 
-        $this->assertCount(2, $result);
-        $this->assertArrayHasKey('aggregate_type', $result[0]);
-        $this->assertArrayHasKey('aggregate_id', $result[0]);
-        $this->assertArrayHasKey('aggregate_type', $result[1]);
-        $this->assertArrayHasKey('aggregate_id', $result[1]);
-        $this->assertEquals(User::class, $result[0]['aggregate_type']);
-        $this->assertEquals(User::class, $result[1]['aggregate_type']);
+        $this->assertCount(1, $this->result);
+        $this->assertArrayHasKey('aggregate_type', $this->result[0]);
+        $this->assertArrayHasKey('aggregate_id', $this->result[0]);
+        $this->assertEquals(User::class, $this->result[0]['aggregate_type']);
     }
 }