搜索
首页后端开发php教程Symfony2源码分析——启动过程2,symfony2源码_PHP教程

Symfony2源码分析——启动过程2,symfony2源码

  上一篇分析Symfony2框架源码,探究Symfony2如何完成一个请求的前半部分,前半部分可以理解为Symfony2框架为处理请求做准备工作,包括container生成、缓存、bundls初始化等一些列准备工作(Symfony2源码分析——启动过程1)。而这一篇讲的是Symfony2如何根据请求的数据生成Response对象,向客户端返回响应数据。

  在分析前需要了解Symfony2的事件驱动机制:Symfony2事件驱动。

  言归正传,Symfony2请求的工作流程其实是Symfony2内核的事件驱动完成的,下面是Symfony2框架定义好的内核事件:

Symfony2源码分析——启动过程2,symfony2源码_PHP教程final class KernelEvents { /** * The REQUEST event occurs at the very beginning of request * dispatching * * This event allows you to create a response for a request before any * other code in the framework is executed. The event listener method * receives a Symfony\Component\HttpKernel\Event\GetResponseEvent * instance. * * @var string * * @api */ const REQUEST = 'kernel.request'; /** * The EXCEPTION event occurs when an uncaught exception appears * * This event allows you to create a response for a thrown exception or * to modify the thrown exception. The event listener method receives * a Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent * instance. * * @var string * * @api */ const EXCEPTION = 'kernel.exception'; /** * The VIEW event occurs when the return value of a controller * is not a Response instance * * This event allows you to create a response for the return value of the * controller. The event listener method receives a * Symfony\Component\HttpKernel\Event\GetResponseForControllerResultEvent * instance. * * @var string * * @api */ const VIEW = 'kernel.view'; /** * The CONTROLLER event occurs once a controller was found for * handling a request * * This event allows you to change the controller that will handle the * request. The event listener method receives a * Symfony\Component\HttpKernel\Event\FilterControllerEvent instance. * * @var string * * @api */ const CONTROLLER = 'kernel.controller'; /** * The RESPONSE event occurs once a response was created for * replying to a request * * This event allows you to modify or replace the response that will be * replied. The event listener method receives a * Symfony\Component\HttpKernel\Event\FilterResponseEvent instance. * * @var string * * @api */ const RESPONSE = 'kernel.response'; /** * The TERMINATE event occurs once a response was sent * * This event allows you to run expensive post-response jobs. * The event listener method receives a * Symfony\Component\HttpKernel\Event\PostResponseEvent instance. * * @var string */ const TERMINATE = 'kernel.terminate'; /** * The FINISH_REQUEST event occurs when a response was generated for a request. * * This event allows you to reset the global and environmental state of * the application, when it was changed during the request. * * @var string */ const FINISH_REQUEST = 'kernel.finish_request'; } View Code

  我们可以编写事件监听器,监听相应的内核事件,在Symfony2触发该事件的时候,相应的事件监听器就会执行。监听和唤醒形象的描述,就像,你(事件监听器)参加校运会,去大会(Symfony2)登记(监听)参加50米短跑(事件),当50米短跑比赛开始了(事件被触发),那你就奔跑吧(监听器执行,其实就是一个执行函数,函数完成什么工作就取决于你的需求了),少年。

  Symfony2的内核事件处理流程大部分工作都在HttpKernel::handleRaw方法中:

<span> 1</span>     <span>private</span> function handleRaw(Request $request, $type =<span> self::MASTER_REQUEST)
</span><span> 2</span> <span>    {
</span><span> 3</span>         $<span>this</span>->requestStack-><span>push($request);
</span><span> 4</span> 
<span> 5</span>         <span>//</span><span> request
</span><span> 6</span>         <span>//</span><span> 初始化事件,事件对象会被传递给监听器,所以事件可以说是一个信息的载体,事件内存放着监听器感兴趣的数据。</span>
<span> 7</span>         $<span>event</span> = <span>new</span> GetResponseEvent($<span>this</span><span>, $request, $type);
</span><span> 8</span>         <span>//</span><span> 触发kernel.request事件,后续详细讲解EventDispatcher::dispatch方法的实现,
</span><span> 9</span>         <span>//</span><span> 这里我们需要知道的是,dispatcher把$event传递给所有监听了kernel.request事件的监听器,监听器将会执行。
</span><span>10</span>         <span>//</span><span> kernel.request事件发生在controller执行之前,我们可以在这一步奏完成路由解析等为controller执行提供准备数据,
</span><span>11</span>         <span>//</span><span> 在这个过程允许我们直接生成Response对象,向客户端输出数据,那么controller就不会被执行了。</span>
<span>12</span>         $<span>this</span>->dispatcher->dispatch(KernelEvents::REQUEST, $<span>event</span><span>);
</span><span>13</span> 
<span>14</span>         <span>//</span><span> 如果我们在kernel.request事件生成了Response对象(响应数据),那么就跳过kernel.controller、kernel.view事件、
</span><span>15</span>         <span>//</span><span> controller也会被跳过,直接执行kernel.response事件。</span>
<span>16</span>         <span>if</span> ($<span>event</span>-><span>hasResponse()) {
</span><span>17</span>             <span>return</span> $<span>this</span>->filterResponse($<span>event</span>-><span>getResponse(), $request, $type);
</span><span>18</span> <span>        }
</span><span>19</span> 
<span>20</span>         <span>//</span><span> load controller
</span><span>21</span>         <span>//</span><span> 根据路由规则返回 一个对象或者数组或者字符串 ,如果$controller是一个数组,$controller[0]是存放的是要执行的controller对象,
</span><span>22</span>         <span>//</span><span> $controller[0]存放的是controller对象执行的方法,即action,方法的参数没有保存在$controller数组中;
</span><span>23</span>         <span>//</span><span> 如果$controller是对象,那么该对象就实现了__invoke 方法;
</span><span>24</span>         <span>//</span><span> 如果$controller是字符串,那么$controller就是要运行的函数的函数名。
</span><span>25</span>         <span>//</span><span> 图2是$controller的一个var_dump例子</span>
<span>26</span>         <span>if</span> (<span>false</span> === $controller = $<span>this</span>->resolver-><span>getController($request)) {
</span><span>27</span>             <span>throw</span> <span>new</span> NotFoundHttpException(sprintf(<span>'</span><span>Unable to find the controller for path "%s". Maybe you forgot to add the matching route in your routing configuration?</span><span>'</span>, $request-><span>getPathInfo()));
</span><span>28</span> <span>        }
</span><span>29</span> 
<span>30</span>         $<span>event</span> = <span>new</span> FilterControllerEvent($<span>this</span><span>, $controller, $request, $type);
</span><span>31</span>         <span>//</span><span> 触发kernel.controller事件,这个事件发生在controller执行前。我们可以通过监听这个事件在controller执行前修改controller,
</span><span>32</span>         <span>//</span><span> 或者完成一些动作。</span>
<span>33</span>         $<span>this</span>->dispatcher->dispatch(KernelEvents::CONTROLLER, $<span>event</span><span>);
</span><span>34</span>         $controller = $<span>event</span>-><span>getController();
</span><span>35</span> 
<span>36</span>         <span>//</span><span> controller arguments
</span><span>37</span>         <span>//</span><span> 从request对象中获取controller方法的参数</span>
<span>38</span>         $arguments = $<span>this</span>->resolver-><span>getArguments($request, $controller);
</span><span>39</span> 
<span>40</span>         <span>//</span><span> call controller
</span><span>41</span>         <span>//</span><span> 执行controller</span>
<span>42</span>         $response =<span> call_user_func_array($controller, $arguments);
</span><span>43</span> 
<span>44</span>         <span>//</span><span> view
</span><span>45</span>         <span>//</span><span> 如果$response不是Response对象,那么kernel.view事件就会触发,监听kernel.view事件的监听器通过$response值生成Response对象。</span>
<span>46</span>         <span>if</span> (!<span>$response instanceof Response) {
</span><span>47</span>             $<span>event</span> = <span>new</span> GetResponseForControllerResultEvent($<span>this</span><span>, $request, $type, $response);
</span><span>48</span>             $<span>this</span>->dispatcher->dispatch(KernelEvents::VIEW, $<span>event</span><span>);
</span><span>49</span> 
<span>50</span>             <span>if</span> ($<span>event</span>-><span>hasResponse()) {
</span><span>51</span>                 $response = $<span>event</span>-><span>getResponse();
</span><span>52</span> <span>            }
</span><span>53</span> 
<span>54</span>             <span>if</span> (!<span>$response instanceof Response) {
</span><span>55</span>                 $msg = sprintf(<span>'</span><span>The controller must return a response (%s given).</span><span>'</span>, $<span>this</span>-><span>varToString($response));
</span><span>56</span> 
<span>57</span>                 <span>//</span><span> the user may have forgotten to return something</span>
<span>58</span>                 <span>if</span> (<span>null</span> ===<span> $response) {
</span><span>59</span>                     $msg .= <span>'</span><span> Did you forget to add a return statement somewhere in your controller?</span><span>'</span><span>;
</span><span>60</span> <span>                }
</span><span>61</span>                 <span>throw</span> <span>new</span><span> \LogicException($msg);
</span><span>62</span> <span>            }
</span><span>63</span> <span>        }
</span><span>64</span> 
<span>65</span>         <span>//</span><span> 触发kernel.response事件,在向客户端输出Response对象前,我们可以对Response对象进行修改,
</span><span>66</span>         <span>//</span><span> 例如修改response头部,设置缓存、压缩输出数据等。
</span><span>67</span> 
<span>68</span>         <span>//</span><span> 接着触发kernel.finish_request事件,把当前请求从请求栈中弹出,当前请求就完成。</span>
<span>69</span>         <span>return</span> $<span>this</span>-><span>filterResponse($response, $request, $type);
</span><span>70</span> 
<span>71</span>         <span>//</span><span> 千万别忘记了,filterResponse执行完后,Symfony2内核事件处理流程还有最后一步,位于app_dev.php[app.php]最后一行,
</span><span>72</span>         <span>//</span><span> $kernel->terminate($request, $response);这个方法触发kernel.terminate事件,此时,Symfony2已经响应了客户端的请求,
</span><span>73</span>         <span>//</span><span> 向客户端输出了Response对象。监听kernel.terminate事件的监听器,主要是为了完成一些耗时的操作,操作的结果不需要返回给
</span><span>74</span>         <span>//</span><span> 客户端的,例如邮件发送、图片压缩等等。
</span><span>75</span>         <span>//</span><span> 到这里,Symfony2的整个流程就走完了。</span>
<span>76</span>     }
<span>HttpKernel::filterResponse方法和</span>HttpKernel::finishRequest方法:
Symfony2源码分析——启动过程2,symfony2源码_PHP教程 1 private function filterResponse(Response $response, Request $request, $type) 2 { 3 $event = new FilterResponseEvent($this, $request, $type, $response); 4 5 $this->dispatcher->dispatch(KernelEvents::RESPONSE, $event); 6 7 $this->finishRequest($request, $type); 8 9 return $event->getResponse(); 10 } 11 12 /** 13 * Publishes the finish request event, then pop the request from the stack. 14 * 15 * Note that the order of the operations is important here, otherwise 16 * operations such as {@link RequestStack::getParentRequest()} can lead to 17 * weird results. 18 * 19 * @param Request $request 20 * @param int $type 21 */ 22 private function finishRequest(Request $request, $type) 23 { 24 $this->dispatcher->dispatch(KernelEvents::FINISH_REQUEST, new FinishRequestEvent($this, $request, $type)); 25 $this->requestStack->pop(); 26 } View Code

图2

Symfony2框架的事件分发机制的核心代码:

<span> 1</span>     <span>public</span> function dispatch($eventName, Event $<span>event</span> = <span>null</span><span>)
</span><span> 2</span> <span>    {
</span><span> 3</span>         <span>if</span> (<span>null</span> === $<span>event</span><span>) {
</span><span> 4</span>             $<span>event</span> = <span>new</span><span> Event();
</span><span> 5</span> <span>        }
</span><span> 6</span> 
<span> 7</span>         $<span>event</span>->setDispatcher($<span>this</span><span>);
</span><span> 8</span>         $<span>event</span>-><span>setName($eventName);
</span><span> 9</span> 
<span>10</span>         <span>if</span> (!isset($<span>this</span>-><span>listeners[$eventName])) {
</span><span>11</span>             <span>return</span> $<span>event</span><span>;
</span><span>12</span> <span>        }
</span><span>13</span> 
<span>14</span>         <span>//</span><span> $eventName即:KernelEvents::REQUEST、KernelEvents::CONTROLLER、KernelEvents::VIEW、KernelEvents::RESPONSE、KernelEvents::TERMINATE等
</span><span>15</span>         <span>//</span><span> getListeners返回所有监听$eventName事件的监听器</span>
<span>16</span>         $<span>this</span>->doDispatch($<span>this</span>->getListeners($eventName), $eventName, $<span>event</span><span>);
</span><span>17</span> 
<span>18</span>         <span>return</span> $<span>event</span><span>;
</span><span>19</span> <span>    }
</span><span>20</span> 
<span>21</span>     <span>protected</span> function doDispatch($listeners, $eventName, Event $<span>event</span><span>)
</span><span>22</span> <span>    {
</span><span>23</span>         <span>//</span><span> 监听器执行</span>
<span>24</span>         <span>foreach</span> ($listeners <span>as</span><span> $listener) {
</span><span>25</span>             call_user_func($listener, $<span>event</span>, $eventName, $<span>this</span><span>);
</span><span>26</span>             <span>//</span><span> 如果其中一个监听器把$event的propagationStopped属性设置为true,那么表示$eventName这一事件终止执行,
</span><span>27</span>             <span>//</span><span> 事件不会往$listeners里尚未执行的监听器传递该事件。</span>
<span>28</span>             <span>if</span> ($<span>event</span>-><span>isPropagationStopped()) {
</span><span>29</span>                 <span>break</span><span>;
</span><span>30</span> <span>            }
</span><span>31</span> <span>        }
</span><span>32</span>     }

 

有没有哪本书具体讲linux内核启动过程的,详细点的(最好具体到实际代码),最好内核针对于26以后的

我个人感觉毛德操先生的书linux内核情景分析,分析的很透彻的,对整个Linux内核的讲解很不错.具体到启动过程,这个启动过程很泛的,你只需要知道整体的启动过程,其他的细节,还得看内核源码讲解,所以,推荐你看点博客了解下启动大体过程,具体到每个细节,看linux内核情景分析吧.
 

android 21的源码分析之长按电源键弹出对话框功可以更改

1.这个dialog是由PhoneWindowManager控制的,在PhoneWindowManager的interceptKeyTq方法中,代码是这一行

mHandler.postDelayed(mPowerLongPress, ViewConfiguration.getGlobalActionKeyTimeout());

mProwerLongPress是一个Runnable,执行时调用GlobalActions中的showDialog方法。所以这个dialog是由GlobalActions管理的,PowerDialog是之前版本中的,现在已经弃用了。

2.可以在GlobalActions中createDialog方法中mSilentModeToggle action的onToggle方法中加入

mAudioManager.setVibrateSetting(AudioManager.VIBRATE_TYPE_RINGER, on ? AudioManager.VIBRATE_SETTING_ON : AudioManager.VIBRATE_SETTING_OFF);

这一句,仿照铃声的处理,应该没问题,不过没试所以也不能确定。

希望对你有帮助。
 

www.bkjia.comtruehttp://www.bkjia.com/PHPjc/899447.htmlTechArticleSymfony2源码分析——启动过程2,symfony2源码 上一篇分析Symfony2框架源码,探究Symfony2如何完成一个请求的前半部分,前半部分可以理解为Sy...
声明
本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系admin@php.cn
继续使用PHP:耐力的原因继续使用PHP:耐力的原因Apr 19, 2025 am 12:23 AM

PHP仍然流行的原因是其易用性、灵活性和强大的生态系统。1)易用性和简单语法使其成为初学者的首选。2)与web开发紧密结合,处理HTTP请求和数据库交互出色。3)庞大的生态系统提供了丰富的工具和库。4)活跃的社区和开源性质使其适应新需求和技术趋势。

PHP和Python:探索他们的相似性和差异PHP和Python:探索他们的相似性和差异Apr 19, 2025 am 12:21 AM

PHP和Python都是高层次的编程语言,广泛应用于Web开发、数据处理和自动化任务。1.PHP常用于构建动态网站和内容管理系统,而Python常用于构建Web框架和数据科学。2.PHP使用echo输出内容,Python使用print。3.两者都支持面向对象编程,但语法和关键字不同。4.PHP支持弱类型转换,Python则更严格。5.PHP性能优化包括使用OPcache和异步编程,Python则使用cProfile和异步编程。

PHP和Python:解释了不同的范例PHP和Python:解释了不同的范例Apr 18, 2025 am 12:26 AM

PHP主要是过程式编程,但也支持面向对象编程(OOP);Python支持多种范式,包括OOP、函数式和过程式编程。PHP适合web开发,Python适用于多种应用,如数据分析和机器学习。

PHP和Python:深入了解他们的历史PHP和Python:深入了解他们的历史Apr 18, 2025 am 12:25 AM

PHP起源于1994年,由RasmusLerdorf开发,最初用于跟踪网站访问者,逐渐演变为服务器端脚本语言,广泛应用于网页开发。Python由GuidovanRossum于1980年代末开发,1991年首次发布,强调代码可读性和简洁性,适用于科学计算、数据分析等领域。

在PHP和Python之间进行选择:指南在PHP和Python之间进行选择:指南Apr 18, 2025 am 12:24 AM

PHP适合网页开发和快速原型开发,Python适用于数据科学和机器学习。1.PHP用于动态网页开发,语法简单,适合快速开发。2.Python语法简洁,适用于多领域,库生态系统强大。

PHP和框架:现代化语言PHP和框架:现代化语言Apr 18, 2025 am 12:14 AM

PHP在现代化进程中仍然重要,因为它支持大量网站和应用,并通过框架适应开发需求。1.PHP7提升了性能并引入了新功能。2.现代框架如Laravel、Symfony和CodeIgniter简化开发,提高代码质量。3.性能优化和最佳实践进一步提升应用效率。

PHP的影响:网络开发及以后PHP的影响:网络开发及以后Apr 18, 2025 am 12:10 AM

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

PHP类型提示如何起作用,包括标量类型,返回类型,联合类型和无效类型?PHP类型提示如何起作用,包括标量类型,返回类型,联合类型和无效类型?Apr 17, 2025 am 12:25 AM

PHP类型提示提升代码质量和可读性。1)标量类型提示:自PHP7.0起,允许在函数参数中指定基本数据类型,如int、float等。2)返回类型提示:确保函数返回值类型的一致性。3)联合类型提示:自PHP8.0起,允许在函数参数或返回值中指定多个类型。4)可空类型提示:允许包含null值,处理可能返回空值的函数。

See all articles

热AI工具

Undresser.AI Undress

Undresser.AI Undress

人工智能驱动的应用程序,用于创建逼真的裸体照片

AI Clothes Remover

AI Clothes Remover

用于从照片中去除衣服的在线人工智能工具。

Undress AI Tool

Undress AI Tool

免费脱衣服图片

Clothoff.io

Clothoff.io

AI脱衣机

AI Hentai Generator

AI Hentai Generator

免费生成ai无尽的。

热工具

Dreamweaver Mac版

Dreamweaver Mac版

视觉化网页开发工具

记事本++7.3.1

记事本++7.3.1

好用且免费的代码编辑器

mPDF

mPDF

mPDF是一个PHP库,可以从UTF-8编码的HTML生成PDF文件。原作者Ian Back编写mPDF以从他的网站上“即时”输出PDF文件,并处理不同的语言。与原始脚本如HTML2FPDF相比,它的速度较慢,并且在使用Unicode字体时生成的文件较大,但支持CSS样式等,并进行了大量增强。支持几乎所有语言,包括RTL(阿拉伯语和希伯来语)和CJK(中日韩)。支持嵌套的块级元素(如P、DIV),

安全考试浏览器

安全考试浏览器

Safe Exam Browser是一个安全的浏览器环境,用于安全地进行在线考试。该软件将任何计算机变成一个安全的工作站。它控制对任何实用工具的访问,并防止学生使用未经授权的资源。

适用于 Eclipse 的 SAP NetWeaver 服务器适配器

适用于 Eclipse 的 SAP NetWeaver 服务器适配器

将Eclipse与SAP NetWeaver应用服务器集成。