Merge pull request #7 from lemonde/WEB-1282/refactor/circuit-breaker

feat(cb): ajoute un trait pour l'utilisation du CircuitBreaker

Service/CircuitBreakerService.php

@@ -14,6 +14,9 @@ class CircuitBreakerService
     const CLOSED = 'closed';
     const HALFOPEN = 'half-open';
 
+    const STATUS_UP = true;
+    const STATUS_DOWN = false;
+
     /**
      * @var AbstractAdapter
      */

Tests/Traits/CircuitBreakerAwareTraitTest.php

@@ -0,0 +1,79 @@
+<?php
+
+namespace Tests\CircuitBreakerBundle\Traits;
+
+use CircuitBreakerBundle\Event\CircuitBreakerEvent;
+use CircuitBreakerBundle\Service\CircuitBreakerService;
+use CircuitBreakerBundle\Traits\CircuitBreakerAwareTrait;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+
+class CircuitBreakerAwareTraitTest extends \PHPUnit_Framework_TestCase
+{
+    private $eventDispatcher;
+    private $circuitBreaker;
+
+    protected function setUp()
+    {
+        $this->eventDispatcher = $this->createMock(EventDispatcherInterface::class);
+        $this->circuitBreaker = $this->createMock(CircuitBreakerService::class);
+    }
+
+
+    public function testSetCircuitBreaker()
+    {
+        $trait = $this->getMockForTrait(CircuitBreakerAwareTrait::class);
+
+        $trait->setCircuitBreaker($this->circuitBreaker);
+
+        $this->assertSame(
+            $this->circuitBreaker,
+            \PHPUnit_Framework_Assert::readAttribute($trait, 'circuitBreaker')
+        );
+    }
+
+    public function testSetEventDispatcher()
+    {
+        $trait = $this->getMockForTrait(CircuitBreakerAwareTrait::class);
+
+        $trait->setEventDispatcher($this->eventDispatcher);
+
+        $this->assertSame(
+            $this->eventDispatcher,
+            \PHPUnit_Framework_Assert::readAttribute($trait, 'eventDispatcher')
+        );
+    }
+
+    public function testNotifyServiceIsDown()
+    {
+        $trait = $this->getMockForTrait(CircuitBreakerAwareTrait::class);
+        $trait->setEventDispatcher($this->eventDispatcher);
+
+        $this->eventDispatcher
+            ->expects($this->once())
+            ->method('dispatch')
+            ->with('circuit.breaker', $this->callback(function ($event) {
+                return $event instanceof CircuitBreakerEvent
+                    && $event->getKey() === 'test_service'
+                    && $event->getStatus() === CircuitBreakerService::STATUS_DOWN;
+            }));
+
+        $trait->notifyServiceIsDown('test_service');
+    }
+
+    public function testNotifyServiceIsUp()
+    {
+        $trait = $this->getMockForTrait(CircuitBreakerAwareTrait::class);
+        $trait->setEventDispatcher($this->eventDispatcher);
+
+        $this->eventDispatcher
+            ->expects($this->once())
+            ->method('dispatch')
+            ->with('circuit.breaker', $this->callback(function ($event) {
+                return $event instanceof CircuitBreakerEvent
+                    && $event->getKey() === 'test_service'
+                    && $event->getStatus() === CircuitBreakerService::STATUS_UP;
+            }));
+
+        $trait->notifyServiceIsUp('test_service');
+    }
+}

Traits/CircuitBreakerAwareTrait.php

@@ -0,0 +1,65 @@
+<?php declare(strict_types = 1);
+
+namespace CircuitBreakerBundle\Traits;
+
+use CircuitBreakerBundle\Service\CircuitBreakerService;
+use CircuitBreakerBundle\Event\CircuitBreakerEvent;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+
+trait CircuitBreakerAwareTrait
+{
+    /**
+     * @var CircuitBreakerService
+     */
+    private $circuitBreaker;
+
+    /**
+     * @var EventDispatcherInterface
+     */
+    private $eventDispatcher;
+
+    /**
+     * Set the circuit breaker service
+     *
+     * @param CircuitBreakerService $circuitBreaker
+     */
+    public function setCircuitBreaker(CircuitBreakerService $circuitBreaker)
+    {
+        $this->circuitBreaker = $circuitBreaker;
+    }
+
+    /**
+     * @param EventDispatcherInterface $eventDispatcher
+     */
+    public function setEventDispatcher(EventDispatcherInterface $eventDispatcher)
+    {
+        $this->eventDispatcher = $eventDispatcher;
+    }
+
+
+    /**
+     * Send an event to notify the circuit breaker that a given service is down
+     *
+     * @param string $serviceName The service which is down
+     */
+    public function notifyServiceIsDown(string $serviceName)
+    {
+        $this->eventDispatcher->dispatch(
+            'circuit.breaker',
+            new CircuitBreakerEvent($serviceName, CircuitBreakerService::STATUS_DOWN)
+        );
+    }
+
+    /**
+     * Send an event to notify the circuit breaker that a given service is up
+     *
+     * @param string $serviceName The service which is up
+     */
+    public function notifyServiceIsUp(string $serviceName)
+    {
+        $this->eventDispatcher->dispatch(
+            'circuit.breaker',
+            new CircuitBreakerEvent($serviceName, CircuitBreakerService::STATUS_UP)
+        );
+    }
+}