<?php namespace Laravel;
// /laravel/laravel.php
/**
 * Bootstrap the core framework components like the IoC container and
 * the configuration class, and the class auto-loader. Once this file
 * has run, the framework is essentially ready for use.
 * 启动核心框架组件，像IOC容器和配置类，以及自动加载类。一旦这个文件运行，框架就基本可以使用了
 */
require 'core.php';

/**
 * Register the PHP exception handler. The framework throws exceptions
 * on every error that cannot be handled. All of those exceptions will
 * be sent through this closure for processing.
 * 注册异常处理器。当任何不能处理的错误发生时框架就抛出异常，所有这些异常将被发送到闭包中处理
 */
// set_exception_handler() 自定义异常处理函数
set_exception_handler(function($e)
{
    // 调用错误类函数exception处理异常
	Error::exception($e);
});

/**
 * Register the PHP error handler. All PHP errors will fall into this
 * handler which will convert the error into an ErrorException object
 * and pass the exception into the exception handler.
 * 注册PHP错误处理器。所有的PHP错误都将放入这个处理器，将错误转为ErrorException对象，然后将这个异常传递给处理器进行处理
 */
set_error_handler(function($code, $error, $file, $line)
{
    // 处理原生的PHP错误
	Error::native($code, $error, $file, $line);
});

/**
 * Register the shutdown handler. This function will be called at the
 * end of the PHP script or on a fatal PHP error. If a PHP error has
 * occured, we will convert it to an ErrorException and pass it
 * to the common exception handler for the framework.
 * 注册关闭处理器。这个函数将在PHP脚本运行结束或者发证致命的PHP错误时被调用。
 * 如果PHP错误发生了，将会把它转为一个ErrorException，然后将它作为参数传递给框架的公共异常处理器
 */
// register_shutdown_function() 注册一个在PHP中止时执行的函数
register_shutdown_function(function()
{
	Error::shutdown();
});

/**
 * Setting the PHP error reporting level to -1 essentially forces
 * PHP to report every error, and it is guranteed to show every
 * error on future versions of PHP.
 *
 * If error detail is turned off, we will turn off all PHP error
 * reporting and display since the framework will be displaying
 * a generic message and we do not want any sensitive details
 * about the exception leaking into the views.
 *
 */
// 报告所有PHP错误
error_reporting(-1);
// init_set()为配置项设置值, display_errors 是否显示错误 在application/config/errors中配置display, 默认关闭
ini_set('display_errors', Config::get('error.display'));

/**
 * Determine if we need to set the application key to a very random
 * string so we can provide a zero configuration installation but
 * still ensure that the key is set to something random. It is
 * possible to disable this feature.
 * 判断是否需要给应用设置一个随机的字符串作为应用key,这样我们可以零配置安装，而且还能确保key是随机的。未来也可能不可用。
 */
// 在application/config/application.php中配置auto_key
$auto_key = Config::get('application.auto_key');

// 若auto_key为true 且key为空，则自动生成key
if ($auto_key and Config::get('application.key') == '')
{
    // ob_start() 打开输出控制缓冲
	ob_start() and with(new CLI\Tasks\Key)->generate();
    // ob_end_clean() 清空缓冲区并关闭输出缓冲
	ob_end_clean();
}

/**
 * Even though "Magic Quotes" are deprecated in PHP 5.3, they may
 * still be enabled on the server. To account for this, we will
 * strip slashes on all input arrays if magic quotes are turned
 * on for the server environment.
 * 即使Magic Quotes 在php5.3被废弃了，它们可能还能使用，未来解决这个问题，
 * 如果服务器环境magic quotes开启的话，我们在所有输入数组添加斜杠
 */
// php5.3之后magic_quotes() 返回false
if (magic_quotes())
{
	$magics = array(&$_GET, &$_POST, &$_COOKIE, &$_REQUEST);

	foreach ($magics as &$magic)
	{
	    // array_strop_slashed() 函数在helpers.php中
        // 遍历数组，删除斜杠
		$magic = array_strip_slashes($magic);
	}
}

/**
 * Load the session using the session manager. The payload will
 * be set on a static property of the Session class for easy
 * access throughout the framework and application.
 * 用session管理器加载session,
 * 设置成Session类的静态属性上，为了框架和应用更容易使用它
 */
if (Config::get('session.driver') !== '')
{
	Session::start(Config::get('session.driver'));

	Session::load(Cookie::get(Config::get('session.cookie')));
}

/**
 * Gather the input to the application based on the global input
 * variables for the current request. The input will be gathered
 * based on the current request method and will be set on the
 * Input manager class' static $input property.
 * 定义全局input遍历手机应用的输入。
 * 当前的请求方法将被设置在Input管理类的静态input属性
 */
$input = array();

switch (Request::method())
{
	case 'GET':
		$input = $_GET;
		break;

	case 'POST':
		$input = $_POST;
		break;

	case 'PUT':
	case 'DELETE':
		if (Request::spoofed())
		{
			$input = $_POST;
		}
		else
		{
		    // file_get_contents() 将整个文件读入一个字符串
            // parse_str() 将字符串解析成多个变量
			parse_str(file_get_contents('php://input'), $input);

			if (magic_quotes()) $input = array_strip_slashes($input);
		}
}

/**
 * The spoofed request method is removed from the input so it is not
 * unexpectedly included in Input::all() or Input::get(). Leaving it
 * in the input array could cause unexpected results if an Eloquent
 * model is filled with the input.
 * 伪造的请求方法将被从inout中移除，被包含在Input:all()或者Input::get()并不意外。
 * 如果一个Eloquent模型被填充到input中，放在input数组中可能造成意外的结果。
 */
// 释放伪造的请求方法
unset($input[Request::spoofer]);

Input::$input = $input;

/**
 * Load the "application" bundle. Though the application folder is
 * not typically considered a bundle, it is started like one and
 * essentially serves as the "default" bundle.
 * 加载application
 * 尽管通常不将application文件夹视为绑定，实际上充当一个默认的绑定进行启动
 */
Bundle::start(DEFAULT_BUNDLE);

/**
 * Auto-start any bundles configured to start on every request.
 * This is especially useful for debug bundles or bundles that
 * are used throughout the application.
 * 对于每一个请求将自动启动配置中的绑定
 * 这对于调试绑定或整个应用程序中使用的绑定特别有用。
 */

foreach (Bundle::$bundles as $bundle => $config)
{
	if ($config['auto']) Bundle::start($bundle);
}

/**
 * Register the "catch-all" route that handles 404 responses for
 * routes that can not be matched to any other route within the
 * application. We'll just raise the 404 event.
 * 注册catch-all路由，用来匹配应用中无法匹配的任何路由，从而进行404响应
 * 只触发404事件
 */
Routing\Router::register('*', '(:all)', function()
{
	return Event::first('404');
});

/**
 * If the requset URI has too many segments, we will bomb out of
 * the request. This is too avoid potential DDoS attacks against
 * the framework by overloading the controller lookup method
 * with thousands of segments.
 * 如果请求URI中分段过多，我们将终止请求
 * 这也避免了通过数千个网段重载控制器查找方法进行DDos攻击
 */
$uri = URI::current();
// URL分段大于15抛出异常
if (count(URI::$segments) > 15)
{
	throw new \Exception("Invalid request. Too many URI segments.");
}

/**
 * Route the request to the proper route in the application. If a
 * route is found, the route will be called via the request class
 * static property. If no route is found, the 404 response will
 * be returned to the browser.
 * 将请求路由到应用中正确的路由
 * 如果一个路由被找到了，这个路由将被通过请求类的静态属性调用
 * 如果路由没有找到，将给浏览器返回404响应
 */
Request::$route = Routing\Router::route(Request::method(), $uri);

$response = Request::$route->call();

/**
 * Close the session and write the active payload to persistent
 * storage. The session cookie will also be written and if the
 * driver is a sweeper, session garbage collection might be
 * performed depending on the "sweepage" probability.
 * 关闭会话，然后将活动的有效负载写入持久性存储。
 * 会话cookie也将被写入，如果驱动程序是扫描程序，则可能会根据“溢出”概率执行会话垃圾回收。
 */
if (Config::get('session.driver') !== '')
{
	Session::save();
}

/**
 * Send all of the cookies to the browser. The cookies are
 * stored in a "jar" until the end of a request, primarily
 * to make testing the cookie functionality of the site
 * much easier since the jar can be inspected.
 * 发送所有的cookie到浏览器。
 * Cookies被存储在jar中，直到请求结束，主要是为了测试网站的cookie功能比jar更容易被侦测到
 */
Cookie::send();	

/**
 * Send the final response to the browser and fire the
 * final event indicating that the processing for the
 * current request is completed.
 * 发送最终的响应到浏览器，而且触发最终的事件来表明当前处理中的请求已经完成
 */
$response->send();

Event::fire('laravel.done');

github地址： https://github.com/liu-shilong/laravel3-scr