typecho流程原理和插件机制浅析（第一弹）
虽然新版本0.9在多次跳票后终于发布了，在漫长的等待里始终有一批人不离不弃，其中不乏一些主题和插件开发者，还有一些忠实的粉丝，但是就是这样一个blog系统还是由于缺乏相关文档和主题插件使很多想要摆脱wp的用户难以跨出最后一步，很多想要学习插件开发的人也因为对机制不了解找不到头绪，今天就简单介绍一下typecho的执行流程和插件机制，并配合一些简单的例子来帮助那些找不到头绪的人，大牛可以路过了！
简要流程分析
Typecho是单入口程序，一切访问都通过index.php，所以还要从index.php的代码开始。(以0.9正式版为例，代码只贴流程必须部分)
if (!@include_once 'config.inc.php') {file_exists('./install.php') ? header('Location: install.php') : print('Missing Config File'); exit; } /** 初始化组件 */ Typecho_Widget::widget('Widget_Init'); /** 注册一个初始化插件 */ Typecho_Plugin::factory('index.php')->begin(); /** 开始路由分发 */ Typecho_Router::dispatch(); /** 注册一个结束插件 */ Typecho_Plugin::factory('index.php')->end(); 整个index.php只做了三件事
- 加载config.inc.php（config.inc.php设置了相关目录、包含路径、加载系统基础类库、 程序初始化
Typecho_Common::init();、最后设置数据库连接参数，此处自行查看） - 执行
Typecho_Widget::widget('Widget_Init'); - 执行
Typecho_Router::dispatch();
那么程序初始化又做了些什么呢？
function __autoLoad($className) { /** * 自动载入函数并不判断此类的文件是否存在, 我们认为当你显式的调用它时, 你已经确认它存在了 * 如果真的无法被加载, 那么系统将出现一个严重错误(Fetal Error) * 如果你需要判断一个类能否被加载, 请使用 Typecho_Common::isAvailableClass 方法 */ @include_once str_replace('_', '/', $className) . '.php'; } 设置自动载入，将Typecho_Widget的_替换为/，并加上.php
即Typecho/Widget.php，并include_once 'Typecho/Widget.php';
执行Typecho_Widght类的Widget静态函数，参数为Widget_Init
public static function widget($alias, $params = NULL, $request = NULL, $enableResponse = true) { list($className) = explode('@', $alias); if (!isset(self::$_widgetPool[$alias])) { $fileName = str_replace('_', '/', $className) . '.php'; require_once $fileName; /** 如果类不存在 */ if (!class_exists($className)) { /** Typecho_Exception */ require_once 'Typecho/Widget/Exception.php'; throw new Typecho_Widget_Exception($className); } /** 初始化request */ if (!empty($request)) { $requestObject = new Typecho_Request(); $requestObject->setParams($request); } else { $requestObject = Typecho_Request::getInstance(); } /** 初始化response */ $responseObject = $enableResponse ? Typecho_Response::getInstance() : Typecho_Widget_Helper_Empty::getInstance(); /** 初始化组件 */ $widget = new $className($requestObject, $responseObject, $params); $widget->execute(); self::$_widgetPool[$alias] = $widget; } return self::$_widgetPool[$alias]; } 同样，将Widget_Init的_替换为/，并加上.php
即Widget/Init.php，并require_once 'Widget/Init.php';
并且执行Widget_Init的execute函数
<?php
/*** Typecho Blog Platform** @copyright Copyright (c) 2008 Typecho team (http://www.typecho.org)* @license GNU General Public License 2.0* @version $Id$ */ /** * 初始化模块 * * @package Widget */ class Widget_Init extends Typecho_Widget { /** * 入口函数,初始化路由器 * * @access public * @return void */ public function execute() { /** 对变量赋值 */ $options = $this->widget('Widget_Options'); /** cookie初始化 */ Typecho_Cookie::setPrefix($options->siteUrl); /** 初始化charset */ Typecho_Common::$charset = $options->charset; /** 初始化exception */ Typecho_Common::$exceptionHandle = 'Widget_ExceptionHandle'; /** 设置路径 */ if (defined('__TYPECHO_PATHINFO_ENCODING__')) { $pathInfo = $this->request->getPathInfo(__TYPECHO_PATHINFO_ENCODING__, $options->charset); } else { $pathInfo = $this->request->getPathInfo(); } Typecho_Router::setPathInfo($pathInfo); /** 初始化路由器 */ Typecho_Router::setRoutes($options->routingTable); /** 初始化插件 */ Typecho_Plugin::init($options->plugins); /** 初始化回执 */ $this->response->setCharset($options->charset); $this->response->setContentType($options->contentType); /** 默认时区 */ if (function_exists("ini_get") && !ini_get("date.timezone") && function_exists("date_default_timezone_set")) { @date_default_timezone_set('UTC'); } /** 初始化时区 */ Typecho_Date::setTimezoneOffset($options->timezone); /** 开始会话, 减小负载只针对后台打开session支持 */ if ($this->widget('Widget_User')->hasLogin()) { @session_start(); } /** 监听缓冲区 */ ob_start(); } } 真正的初始化是在Typecho_Init，其中最重要的两项任务就是
- 获取 pathinfo （比如访问文章
http://localhost/archives/1/，则 pathinfo 为/archives/1/） - 从数据库读取系统路由表（
option表routingTable字段）
举例系统安装完成默认路由
[index] => Array([url] => /[widget] => Widget_Archive[action] => render[regx] => |^[/]?$|[format] => /[params] => Array())[archive] => Array([url] => /blog/[widget] => Widget_Archive[action] => render[regx] => |^/blog[/]?$|[format] => /blog/[params] => Array())[do] => Array([url] => /action/[action:alpha][widget] => Widget_Do[action] => action[regx] => |^/action/([_0-9a-zA-Z-]+)[/]?$|[format] => /action/%s[params] => Array([0] => action))[post] => Array([url] => /archives/[cid:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/archives/([0-9]+)[/]?$|[format] => /archives/%s/[params] => Array([0] => cid))[attachment] => Array([url] => /attachment/[cid:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/attachment/([0-9]+)[/]?$|[format] => /attachment/%s/[params] => Array([0] => cid))[category] => Array([url] => /category/[slug]/[widget] => Widget_Archive[action] => render[regx] => |^/category/([^/]+)[/]?$|[format] => /category/%s/[params] => Array([0] => slug))[tag] => Array([url] => /tag/[slug]/[widget] => Widget_Archive[action] => render[regx] => |^/tag/([^/]+)[/]?$|[format] => /tag/%s/[params] => Array([0] => slug))[author] => Array([url] => /author/[uid:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/author/([0-9]+)[/]?$|[format] => /author/%s/[params] => Array([0] => uid))[search] => Array([url] => /search/[keywords]/[widget] => Widget_Archive[action] => render[regx] => |^/search/([^/]+)[/]?$|[format] => /search/%s/[params] => Array([0] => keywords))[index_page] => Array([url] => /page/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/page/([0-9]+)[/]?$|[format] => /page/%s/[params] => Array([0] => page))[archive_page] => Array([url] => /blog/page/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/blog/page/([0-9]+)[/]?$|[format] => /blog/page/%s/[params] => Array([0] => page))[category_page] => Array([url] => /category/[slug]/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/category/([^/]+)/([0-9]+)[/]?$|[format] => /category/%s/%s/[params] => Array([0] => slug[1] => page))[tag_page] => Array([url] => /tag/[slug]/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/tag/([^/]+)/([0-9]+)[/]?$|[format] => /tag/%s/%s/[params] => Array([0] => slug[1] => page))[author_page] => Array([url] => /author/[uid:digital]/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/author/([0-9]+)/([0-9]+)[/]?$|[format] => /author/%s/%s/[params] => Array([0] => uid[1] => page))[search_page] => Array([url] => /search/[keywords]/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/search/([^/]+)/([0-9]+)[/]?$|[format] => /search/%s/%s/[params] => Array([0] => keywords[1] => page))[archive_year] => Array([url] => /[year:digital:4]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})[/]?$|[format] => /%s/[params] => Array([0] => year))[archive_month] => Array([url] => /[year:digital:4]/[month:digital:2]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})/([0-9]{2})[/]?$|[format] => /%s/%s/[params] => Array([0] => year[1] => month))[archive_day] => Array([url] => /[year:digital:4]/[month:digital:2]/[day:digital:2]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})/([0-9]{2})/([0-9]{2})[/]?$|[format] => /%s/%s/%s/[params] => Array([0] => year[1] => month[2] => day))[archive_year_page] => Array([url] => /[year:digital:4]/page/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})/page/([0-9]+)[/]?$|[format] => /%s/page/%s/[params] => Array([0] => year[1] => page))[archive_month_page] => Array([url] => /[year:digital:4]/[month:digital:2]/page/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})/([0-9]{2})/page/([0-9]+)[/]?$|[format] => /%s/%s/page/%s/[params] => Array([0] => year[1] => month[2] => page))[archive_day_page] => Array([url] => /[year:digital:4]/[month:digital:2]/[day:digital:2]/page/[page:digital]/[widget] => Widget_Archive[action] => render[regx] => |^/([0-9]{4})/([0-9]{2})/([0-9]{2})/page/([0-9]+)[/]?$|[format] => /%s/%s/%s/page/%s/[params] => Array([0] => year[1] => month[2] => day[3] => page))[comment_page] => Array([url] => [permalink:string]/comment-page-[commentPage:digital][widget] => Widget_Archive[action] => render[regx] => |^(.+)/comment\-page\-([0-9]+)[/]?$|[format] => %s/comment-page-%s[params] => Array([0] => permalink[1] => commentPage))[feed] => Array([url] => /feed[feed:string:0][widget] => Widget_Archive[action] => feed[regx] => |^/feed(.*)[/]?$|[format] => /feed%s[params] => Array([0] => feed))[feedback] => Array([url] => [permalink:string]/[type:alpha][widget] => Widget_Feedback[action] => action[regx] => |^(.+)/([_0-9a-zA-Z-]+)[/]?$|[format] => %s/%s[params] => Array([0] => permalink[1] => type))[page] => Array([url] => /[slug].html[widget] => Widget_Archive[action] => render[regx] => |^/([^/]+)\.html[/]?$|[format] => /%s.html[params] => Array([0] => slug)
这个在代码里标为routingTable的东西其实就是程序对不同pathinfo的解析规则。
剩下的活就交给index.php里的Typecho_Router::dispatch();了
这句的注释是/** 开始路由分发 */
接着上边 pathinfo =/archives/1/的例子
dispatch函数将路由表里的[regx]里的正则表达式一一进行正则匹配，发现与[post]的匹配，并1提取作为参数cid的值，并将参数cid=1作为参数提交给Widget_Archive类的render函数，Widget_Archive类根据类型post、cid=1进行数据查询和模板渲染发送给客户端，至此一个简单的执行流程就完成了!
细心的读者可能会发现，为什么系统路由里的怎么都是
[widget] => Widget_Archive
[action] => render
这是因为typecho在类Widget_Archive里还根据不同的访问类型调用了不同的查询函数，这个以后再说！