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<?php |
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namespace NBN\LoadBalancer; |
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use NBN\LoadBalancer\Chooser\ChooserInterface; |
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use NBN\LoadBalancer\Exception\AlreadyRegisteredHostException; |
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use NBN\LoadBalancer\Exception\HostRequestException; |
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use NBN\LoadBalancer\Exception\NoAvailableHostException; |
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use NBN\LoadBalancer\Exception\NoRegisteredHostException; |
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use NBN\LoadBalancer\Host\Host; |
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use NBN\LoadBalancer\Host\HostInterface; |
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use Symfony\Component\HttpFoundation\Request; |
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use Symfony\Component\HttpFoundation\Response; |
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/** |
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* @author Nicolas Bastien <[email protected]> |
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*/ |
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class LoadBalancer implements LoadBalancerInterface |
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{ |
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/** |
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* @var array|HostInterface[] |
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*/ |
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protected $hosts; |
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/** |
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* @var ChooserInterface |
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*/ |
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protected $chooser; |
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/** |
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* @param array|HostInterface[] $hosts |
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* @param ChooserInterface $chooser |
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*/ |
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public function __construct(array $hosts, ChooserInterface $chooser) |
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{ |
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foreach ($hosts as $host) { |
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$this->hosts[$host->getId()] = $host; |
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} |
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$this->chooser = $chooser; |
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} |
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/** |
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* @param HostInterface $host |
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*/ |
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public function addHost(HostInterface $host) |
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{ |
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if (isset($this->hosts[$host->getId()])) { |
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throw new AlreadyRegisteredHostException(); |
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} |
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$this->hosts[$host->getId()] = $host; |
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} |
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/** |
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* @param string $id |
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* @param string $url |
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* @param array $settings |
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*/ |
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public function addHostByConfiguration($id, $url, $settings) |
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{ |
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if (isset($this->hosts[$id])) { |
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throw new AlreadyRegisteredHostException(); |
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} |
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$this->hosts[$id] = new Host($id, $url, $settings); |
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} |
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/** |
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* {@inheritdoc} |
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*/ |
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public function handleRequest(Request $request) |
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{ |
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if (count($this->hosts) == 0) { |
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throw new NoRegisteredHostException(); |
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} |
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$host = $this->chooser->getAvailableHost($request, $this->hosts); |
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if ($host === null) { |
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throw new NoAvailableHostException(); |
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} |
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$response = $host->handleRequest($request); |
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if (!$response instanceof Response) { |
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throw new HostRequestException(); |
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} |
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$response->headers->set('Handled-By', $host->getId()); |
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return $response; |
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} |
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} |
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nicolas-bastien /
LoadBalancer
