laravel中terminate中间件和响应输出的原理

用了terminate中间件之后&＃xff0c;就想看看为什么页面&＃xff08;客户端&＃xff09;输出之后&＃xff0c;terminate方法还能继续执行&＃xff0c;猜想肯定是ob族的函数起作用&＃xff0c;flush出去之后&＃xff0c;php的生命周期还没结束&＃xff0c;还能继续执行其他方法。追代码验证一下。

1. $app->run();一切的起点。

2. run方法位于

\vendor\laravel\lumen-framework\src\Concerns\RoutesRequests.php

的473行&＃xff0c;方法体是这样的

/*** Run the application and send the response.** &＃64;param SymfonyRequest|null $request* &＃64;return void*/public function run($request &＃61; null){$response &＃61; $this->dispatch($request);if ($response instanceof SymfonyResponse) {$response->send();} else {echo (string) $response;}if (count($this->middleware) > 0) {$this->callTerminableMiddleware($response);}}

$response的send方法具体路径为

\vendor\symfony\http-foundation\Response.php

方法体如下&＃xff1a;

public function send(){$this->sendHeaders();$this->sendContent();if (function_exists(&＃39;fastcgi_finish_request&＃39;)) {fastcgi_finish_request();} elseif (&＃39;cli&＃39; !&＃61;&＃61; PHP_SAPI) {static::closeOutputBuffers(0, true);}return $this;}

在fastcgi模式下

(PHP 5 >&＃61; 5.3.3, PHP 7)

fastcgi_finish_request — 冲刷(flush)所有响应的数据给客户端

在非fastcgi和非cli模式下

public static function closeOutputBuffers($targetLevel, $flush){$status &＃61; ob_get_status(true);$level &＃61; count($status);// PHP_OUTPUT_HANDLER_* are not defined on HHVM 3.3$flags &＃61; defined(&＃39;PHP_OUTPUT_HANDLER_REMOVABLE&＃39;) ? PHP_OUTPUT_HANDLER_REMOVABLE | ($flush ? PHP_OUTPUT_HANDLER_FLUSHABLE : PHP_OUTPUT_HANDLER_CLEANABLE) : -1;while ($level-- > $targetLevel && ($s &＃61; $status[$level]) && (!isset($s[&＃39;del&＃39;]) ? !isset($s[&＃39;flags&＃39;]) || ($s[&＃39;flags&＃39;] & $flags) &＃61;&＃61;&＃61; $flags : $s[&＃39;del&＃39;])) {if ($flush) {ob_end_flush();} else {ob_end_clean();}}}

果然就是ob_end_flush