#2: LoadBalancer setup

Makefile

@@ -15,3 +15,8 @@ cs: checkstyle
 checkstyle:
 	vendor/bin/phpcs --extensions=php -n --standard=PSR2 --report=full src
 
+## Test
+test: phpunit
+
+phpunit:
+	vendor/bin/phpunit

composer.json

@@ -11,7 +11,8 @@
     }
   ],
   "require": {
-    "php": "^5.4||^7.0"
+    "php": "^5.4||^7.0",
+    "symfony/http-foundation": "^3.1"
   },
   "require-dev": {
     "phpunit/phpunit": "^5.0||^4.0",

phpunit.xml.dist

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit
+    bootstrap="vendor/autoload.php"
+    colors="true"
+>
+    <testsuites>
+        <testsuite name="LoadBalancer Test Suite">
+            <directory>./tests/</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>

src/Chooser/ChooserInterface.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace NBN\LoadBalancer\Chooser;
+
+/**
+ * @author Nicolas Bastien <[email protected]>
+ */
+interface ChooserInterface
+{
+    /**
+     * @param  Request  $request
+     * @param  array    $hosts
+     * @return Response
+     */
+    public function handleRequest(Request $request, array $hosts);
+}

src/Exception/NoRegisteredHostException.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace NBN\LoadBalancer\Exception;
+
+/**
+ * @author Nicolas Bastien <[email protected]>
+ */
+class NoRegisteredHostException extends \RuntimeException
+{
+}

src/Host/HostInterface.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace NBN\LoadBalancer\Host;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * @author Nicolas Bastien <[email protected]>
+ */
+interface HostInterface
+{
+    /**
+     * @return float
+     */
+    public function getLoad();
+
+    /**
+     * @return Response
+     */
+    public function handleRequest(Request $request);
+}

src/LoadBalancer.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace NBN\LoadBalancer;
+
+use NBN\LoadBalancer\Chooser\ChooserInterface;
+use NBN\LoadBalancer\Exception\NoAvailableHostException;
+use NBN\LoadBalancer\Exception\NoRegisterdHostException;
+use NBN\LoadBalancer\Exception\NoRegisteredHostException;
+use NBN\LoadBalancer\Host\HostInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * @author Nicolas Bastien <[email protected]>
+ */
+class LoadBalancer implements LoadBalancerInterface
+{
+    /**
+     * @var array|HostInterface[]
+     */
+    protected $hosts;
+
+    /**
+     * @var ChooserInterface
+     */
+    protected $chooser;
+
+    /**
+     * @param array|HostInterface[] $hosts
+     * @param ChooserInterface      $chooser
+     */
+    public function __construct(array $hosts, ChooserInterface $chooser)
+    {
+        $this->hosts   = $hosts;
+        $this->chooser = $chooser;
+    }
+
+    public function addHost(HostInterface $host)
+    {
+        $this->hosts[] = $host;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function handleRequest(Request $request)
+    {
+        if (count($this->hosts) == 0) {
+            throw new NoRegisteredHostException();
+        }
+
+    }
+}

src/LoadBalancerInterface.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace NBN\LoadBalancer;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\Response;
+
+/**
+ * @author Nicolas Bastien <[email protected]>
+ */
+interface LoadBalancerInterface
+{
+    /**
+     * Load balance the request according to loadbalancer configuration
+     *
+     * @return Response
+     */
+    public function handleRequest(Request $request);
+}

tests/Unit/LoadBalancerTest.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace NBN\LoadBalancer;
+
+use NBN\LoadBalancer\Exception\NoRegisteredHostException;
+
+/**
+ * vendor/bin/phpunit tests/Unit/LoadBalancerTest.php
+ *
+ * @author Nicolas Bastien <[email protected]>
+ */
+class LoadBalancerTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @test LoadBalancer::handleRequest()
+     */
+    public function testHandleRequestNoHostException()
+    {
+        $chooser  = $this->prophesize('NBN\LoadBalancer\Chooser\ChooserInterface');
+        $resquest = $this->prophesize('Symfony\Component\HttpFoundation\Request');
+
+        $loadBalancer = new LoadBalancer([], $chooser->reveal());
+
+        $this->expectException(NoRegisteredHostException::class);
+        $loadBalancer->handleRequest($resquest->reveal());
+    }
+}