上一篇文章 我們分析了Yaf框架的啓動,包括配置文件的初始化以及框架類的加載。本文將分析Yaf
處理一次Web請求的詳細過程,這是一個Web框架最核心的部分,理解了這點,就理解了Yaf的實現原理。
(一)框架類的實例化
在上一篇文章提到了Yaf框架類的加載,類加載完成後,還要實例化,
我們逐一分析Yaf各個框架類的構造函數。
不急於分析各種調用關係,我們先看下Application啓動後,Yaf的對象關係如圖1-1所示。
圖1-1 Yaf對象關係圖
一切構造從 new Yaf_Application() 開始。
所有類的實例化都從Yaf_Applicaion的構造函數開始,它主要做了這幾件事:
- 實例化Config
- 實例化Request
- 實例化Dispatcher
- 實例化Loader
yaf_application.c
PHP_METHOD(yaf_application, __construct) { //實例化Config,用於讀取配置信息 zconfig = yaf_config_instance(NULL, config, section TSRMLS_CC); //解析application的配置信息,將配置參數保存到全局變量中 yaf_application_parse_option( zend_read_property(yaf_config_ce, zconfig, ZEND_STRL(YAF_CONFIG_PROPERT_NAME), 1 TSRMLS_CC) TSRMLS_CC) //實例化Request,保存請求的信息 request = yaf_request_instance(NULL, YAF_G(base_uri) TSRMLS_CC); //實例化分發器Dispatcher,這是Yaf的核心控制類 zdispatcher = yaf_dispatcher_instance(NULL TSRMLS_CC); yaf_dispatcher_set_request(zdispatcher, request TSRMLS_CC); //把config實例設置成Application的屬性 zend_update_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_CONFIG), zconfig TSRMLS_CC); //把request實例設置成Application的屬性 zend_update_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_DISPATCHER), zdispatcher TSRMLS_CC); //創建loader,用於自動加載類 loader = yaf_loader_instance(NULL, local_library, strlen(YAF_G(global_library))? YAF_G(global_library) : NULL TSRMLS_CC); //把dispatcher設置成Application的屬性 zend_update_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_DISPATCHER), zdispatcher TSRMLS_CC); }
在Yaf_Application的構造函數中,調用其他類的構造函數時,又會繼續創建它依賴的其它對象,
最終所有框架類都完成實例化,形成圖1-1所示的關係圖,然後就可以開始處理用戶的請求了。
(二)處理請求
幾乎所有MVC的Web框架處理一個請求都會走過3個流程,如圖2-1所示。
圖2-1 MVC框架處理請求的流程圖
Yaf也是按照這個流程來處理請求的,更細化一點,Yaf提供了完善的API,
並支持Bootstrap和插件機制,我們引用Yaf官方文檔的流程圖來分析,如圖2-2所示。
圖2-2 Yaf流程圖
從Yaf的流程圖可以看到,一切請求的處理從 run() 方法開始。
yaf_application.c
PHP_METHOD(yaf_application, run) { zval *running; yaf_dispatcher_t *dispatcher; yaf_response_t *response; yaf_application_t *self = getThis(); //確保application的狀態是非running的 running = zend_read_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_RUN), 1 TSRMLS_CC); if (IS_BOOL == Z_TYPE_P(running) && Z_BVAL_P(running)) { yaf_trigger_error(YAF_ERR_STARTUP_FAILED TSRMLS_CC, "An application instance already run"); RETURN_TRUE; } //把application的狀態置爲running ZVAL_BOOL(running, 1); zend_update_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_RUN), running TSRMLS_CC); //調用dispatcher來處理這次請求 dispatcher = zend_read_property(yaf_application_ce, self, ZEND_STRL(YAF_APPLICATION_PROPERTY_NAME_DISPATCHER), 1 TSRMLS_CC); if ((response = yaf_dispatcher_dispatch(dispatcher TSRMLS_CC))) { RETURN_ZVAL(response, 1, 1); } RETURN_FALSE; }
可以看出,run() 函數調用了 yaf_dispatcher_dispatch 來處理請求。繼續探索,等等,先劇透下,
我們來看看接下來的函數調用關係圖,如圖2-3所示。
圖2-3 處理請求的函數調用關係圖
繼續分析yaf_dispatcher_dispatch,它是處理請求的中心函數,它調用路由器完成路由,
然後根據路由結果,找到對應的action執行,最後把結果發送給客戶端。
yaf_dispatcher.c
yaf_response_t * yaf_dispatcher_dispatch(yaf_dispatcher_t *dispatcher TSRMLS_DC) { zval *return_response, *plugins, *view; yaf_response_t *response; yaf_request_t *request; uint nesting = YAF_G(forward_limit); //實例化一個Response,用來返回的數據 response = yaf_response_instance(NULL, sapi_module.name TSRMLS_CC); //取得request對象 request = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_REQUEST), 1 TSRMLS_CC); //取得所有插件 plugins = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_PLUGINS), 1 TSRMLS_CC); if (IS_OBJECT != Z_TYPE_P(request)) { yaf_trigger_error(YAF_ERR_TYPE_ERROR TSRMLS_CC, "Expect a %s instance", yaf_request_ce->name); zval_ptr_dtor(&response); return NULL; } //路由此次請求 if (!yaf_request_is_routed(request TSRMLS_CC)) { //在路由開始前,調用各個插件的route_startup方法 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_ROUTESTARTUP, request, response); YAF_EXCEPTION_HANDLE(dispatcher, request, response); //開始路由,路由的結果是找到處理此次請求的module、controller和action //這幾個結果分別保存在Request對象的$module、$controller和$action變量中 if (!yaf_dispatcher_route(dispatcher, request TSRMLS_CC)) { yaf_trigger_error(YAF_ERR_ROUTE_FAILED TSRMLS_CC, "Routing request failed"); YAF_EXCEPTION_HANDLE_NORET(dispatcher, request, response); zval_ptr_dtor(&response); return NULL; } yaf_dispatcher_fix_default(dispatcher, request TSRMLS_CC); //在路由完成後,調用各個插件的route_shutdown方法 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_ROUTESHUTDOWN, request, response); YAF_EXCEPTION_HANDLE(dispatcher, request, response); (void)yaf_request_set_routed(request, 1 TSRMLS_CC); } else { yaf_dispatcher_fix_default(dispatcher, request TSRMLS_CC); } //在路由結束後,分發循環之前調用各個插件的loop_startup函數 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_LOOPSTARTUP, request, response); YAF_EXCEPTION_HANDLE(dispatcher, request, response); //初始化view view = yaf_dispatcher_init_view(dispatcher, NULL, NULL TSRMLS_CC); if (!view) { return NULL; } //進入分發循環,最多循環 application.forward_limit 次 do { //在請求分發之前執行各個插件的pre_dispatch方法 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_PREDISPATCH, request, response); //調用yaf_dispatcher_handle處理請求 if (!yaf_dispatcher_handle(dispatcher, request, response, view TSRMLS_CC)) { YAF_EXCEPTION_HANDLE(dispatcher, request, response); zval_ptr_dtor(&response); return NULL; } yaf_dispatcher_fix_default(dispatcher, request TSRMLS_CC); //在請求分發結束後,執行各個插件的post_dispatch方法 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_POSTDISPATCH, request, response); YAF_EXCEPTION_HANDLE(dispatcher, request, response); } while (--nesting > 0 && !yaf_request_is_dispatched(request TSRMLS_CC)); //在分發循環結束後,執行各個插件的loop_shutdown方法 YAF_PLUGIN_HANDLE(plugins, YAF_PLUGIN_HOOK_LOOPSHUTDOWN, request, response); YAF_EXCEPTION_HANDLE(dispatcher, request, response); if (0 == nesting && !yaf_request_is_dispatched(request TSRMLS_CC)) { yaf_trigger_error(YAF_ERR_DISPATCH_FAILED TSRMLS_CC, "The max dispatch nesting %ld was reached", YAF_G(forward_limit)); YAF_EXCEPTION_HANDLE_NORET(dispatcher, request, response); zval_ptr_dtor(&response); return NULL; } //取出返回給客戶端的數據 return_response = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_RETURN), 1 TSRMLS_CC); if (!Z_BVAL_P(return_response)) { //將數據發送給客戶端 (void)yaf_response_send(response TSRMLS_CC); yaf_response_clear_body(response, NULL, 0 TSRMLS_CC); } return response; }
路由的工作交給 yaf_dispatcher_route,這裏不分析路由的詳細過程,只需瞭解,路由的目的是找出
處理此次請求的module、controller和action,並把這些信息保存在Request對象中。接下來,由
yaf_dispatcher_handle函數去調用action的方法來處理請求。我們繼續分析 yaf_dispatcher_handle。
yaf_dispatcher.c
int yaf_dispatcher_handle(yaf_dispatcher_t *dispatcher, yaf_request_t *request, yaf_response_t *response, yaf_view_t *view TSRMLS_DC) { zend_class_entry *request_ce; char *app_dir = YAF_G(directory); request_ce = Z_OBJCE_P(request); yaf_request_set_dispatched(request, 1 TSRMLS_CC); if (!app_dir) { yaf_trigger_error(YAF_ERR_STARTUP_FAILED TSRMLS_CC, "%s requires %s(which set the application.directory) to be initialized first", yaf_dispatcher_ce->name, yaf_application_ce->name); return 0; } else { int is_def_module = 0; /* int is_def_ctr = 0; */ zval *module, *controller, *dmodule, *dcontroller, *instantly_flush; zend_class_entry *ce; yaf_controller_t *executor; zend_function *fptr; //從Request對象中讀取路由結果(module、controller) module = zend_read_property(request_ce, request, ZEND_STRL(YAF_REQUEST_PROPERTY_NAME_MODULE), 1 TSRMLS_CC); controller = zend_read_property(request_ce, request, ZEND_STRL(YAF_REQUEST_PROPERTY_NAME_CONTROLLER), 1 TSRMLS_CC); dmodule = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_MODULE), 1 TSRMLS_CC); dcontroller = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_CONTROLLER), 1 TSRMLS_CC); if (Z_TYPE_P(module) != IS_STRING || !Z_STRLEN_P(module)) { yaf_trigger_error(YAF_ERR_DISPATCH_FAILED TSRMLS_CC, "Unexcepted a empty module name"); return 0; } else if (!yaf_application_is_module_name(Z_STRVAL_P(module), Z_STRLEN_P(module) TSRMLS_CC)) { yaf_trigger_error(YAF_ERR_NOTFOUND_MODULE TSRMLS_CC, "There is no module %s", Z_STRVAL_P(module)); return 0; } if (Z_TYPE_P(controller) != IS_STRING || !Z_STRLEN_P(controller)) { yaf_trigger_error(YAF_ERR_DISPATCH_FAILED TSRMLS_CC, "Unexcepted a empty controller name"); return 0; } if(strncasecmp(Z_STRVAL_P(dmodule), Z_STRVAL_P(module), Z_STRLEN_P(module)) == 0) { is_def_module = 1; } /* if (strncasecmp(Z_STRVAL_P(dcontroller), Z_STRVAL_P(controller), Z_STRLEN_P(controller)) == 0) { is_def_ctr = 1; } */ //實例化Controller對象 ce = yaf_dispatcher_get_controller(app_dir, Z_STRVAL_P(module), Z_STRVAL_P(controller), Z_STRLEN_P(controller), is_def_module TSRMLS_CC); if (!ce) { return 0; } else { zval *action, *render, *ret = NULL; char *action_lower, *func_name, *view_dir; uint func_name_len; yaf_controller_t *icontroller; MAKE_STD_ZVAL(icontroller); object_init_ex(icontroller, ce); /* cause controller's constructor is a final method, so it must be a internal function do { zend_function *constructor = NULL; constructor = Z_OBJ_HT_P(exec_ctr)->get_constructor(exec_ctr TSRMLS_CC); if (constructor != NULL) { if (zend_call_method_with_2_params(&exec_ctr, *ce , &constructor, NULL, &ret, request, response) == NULL) { yaf_trigger_error(YAF_ERR_CALL_FAILED, "function call for %s::__construct failed", (*ce)->name); return 0; } } } while(0); */ yaf_controller_construct(ce, icontroller, request, response, view, NULL TSRMLS_CC); if (EG(exception)) { zval_ptr_dtor(&icontroller); return 0; } /* view template directory for application, please notice that view engine's directory has high priority */ if (is_def_module) { spprintf(&view_dir, 0, "%s%c%s", app_dir, DEFAULT_SLASH, "views"); } else { spprintf(&view_dir, 0, "%s%c%s%c%s%c%s", app_dir, DEFAULT_SLASH, "modules", DEFAULT_SLASH, Z_STRVAL_P(module), DEFAULT_SLASH, "views"); } if (YAF_G(view_directory)) { efree(YAF_G(view_directory)); } YAF_G(view_directory) = view_dir; zend_update_property(ce, icontroller, ZEND_STRL(YAF_CONTROLLER_PROPERTY_NAME_NAME), controller TSRMLS_CC); //從Request對象中讀取路由結果(action) action = zend_read_property(request_ce, request, ZEND_STRL(YAF_REQUEST_PROPERTY_NAME_ACTION), 1 TSRMLS_CC); action_lower = zend_str_tolower_dup(Z_STRVAL_P(action), Z_STRLEN_P(action)); php_printf("dispatcher action_lower = %s\n", action_lower); /* because the action might call the forward to override the old action */ Z_ADDREF_P(action); func_name_len = spprintf(&func_name, 0, "%s%s", action_lower, "action"); efree(action_lower); php_printf("dispatcher func_name = %s\n", func_name); if (zend_hash_find(&((ce)->function_table), func_name, func_name_len + 1, (void **)&fptr) == SUCCESS) { //Action是一個定義在Controller類中的成員方法, //就直接調用Controller定義的action方法 uint count = 0; zval ***call_args = NULL; ret = NULL; executor = icontroller; if (fptr->common.num_args) { zval *method_name; yaf_dispatcher_get_call_parameters(request_ce, request, fptr, &call_args, &count TSRMLS_CC); MAKE_STD_ZVAL(method_name); ZVAL_STRINGL(method_name, func_name, func_name_len, 0); call_user_function_ex(&(ce)->function_table, &icontroller, method_name, &ret, count, call_args, 1, NULL TSRMLS_CC); efree(method_name); efree(call_args); } else { zend_call_method(&icontroller, ce, NULL, func_name, func_name_len, &ret, 0, NULL, NULL TSRMLS_CC); } efree(func_name); if (!ret) { zval_ptr_dtor(&action); zval_ptr_dtor(&icontroller); return 0; } if ((Z_TYPE_P(ret) == IS_BOOL && !Z_BVAL_P(ret))) { /* no auto-render */ zval_ptr_dtor(&ret); zval_ptr_dtor(&action); zval_ptr_dtor(&icontroller); return 1; } zval_ptr_dtor(&ret); } else if ((ce = yaf_dispatcher_get_action(app_dir, icontroller, Z_STRVAL_P(module), is_def_module, Z_STRVAL_P(action), Z_STRLEN_P(action) TSRMLS_CC)) && (zend_hash_find(&(ce)->function_table, YAF_ACTION_EXECUTOR_NAME, sizeof(YAF_ACTION_EXECUTOR_NAME), (void **)&fptr) == SUCCESS)) { //Action是一個獨立的類,就實例化這個類,調用其execute方法 zval ***call_args; yaf_action_t *iaction; uint count = 0; efree(func_name); MAKE_STD_ZVAL(iaction); object_init_ex(iaction, ce); yaf_controller_construct(ce, iaction, request, response, view, NULL TSRMLS_CC); executor = iaction; zend_update_property(ce, iaction, ZEND_STRL(YAF_CONTROLLER_PROPERTY_NAME_NAME), controller TSRMLS_CC); zend_update_property(ce, iaction, ZEND_STRL(YAF_ACTION_PROPERTY_NAME_CTRL), icontroller TSRMLS_CC); zval_ptr_dtor(&icontroller); if (fptr->common.num_args) { zval *method_name = NULL; yaf_dispatcher_get_call_parameters(request_ce, request, fptr, &call_args, &count TSRMLS_CC); MAKE_STD_ZVAL(method_name); ZVAL_STRINGL(method_name, YAF_ACTION_EXECUTOR_NAME, sizeof(YAF_ACTION_EXECUTOR_NAME) - 1, 0); call_user_function_ex(&(ce)->function_table, &iaction, method_name, &ret, count, call_args, 1, NULL TSRMLS_CC); efree(method_name); efree(call_args); } else { zend_call_method_with_0_params(&iaction, ce, NULL, "execute", &ret); } if (!ret) { zval_ptr_dtor(&action); zval_ptr_dtor(&iaction); return 0; } if (( Z_TYPE_P(ret) == IS_BOOL && !Z_BVAL_P(ret))) { /* no auto-render */ zval_ptr_dtor(&ret); zval_ptr_dtor(&action); zval_ptr_dtor(&iaction); return 1; } zval_ptr_dtor(&ret); } else { efree(func_name); zval_ptr_dtor(&icontroller); return 0; } if (executor) { /* controller's property can override the Dispatcher's */ int auto_render = 1; render = zend_read_property(ce, executor, ZEND_STRL(YAF_CONTROLLER_PROPERTY_NAME_RENDER), 1 TSRMLS_CC); instantly_flush = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_FLUSH), 1 TSRMLS_CC); if (render == EG(uninitialized_zval_ptr)) { render = zend_read_property(yaf_dispatcher_ce, dispatcher, ZEND_STRL(YAF_DISPATCHER_PROPERTY_NAME_RENDER), 1 TSRMLS_CC); auto_render = Z_BVAL_P(render); } else if (Z_TYPE_P(render) <= IS_BOOL && !Z_BVAL_P(render)) { auto_render = 0; } if (auto_render) { ret = NULL; if (!Z_BVAL_P(instantly_flush)) { zend_call_method_with_1_params(&executor, ce, NULL, "render", &ret, action); zval_ptr_dtor(&executor); if (!ret) { zval_ptr_dtor(&action); return 0; } else if (IS_BOOL == Z_TYPE_P(ret) && !Z_BVAL_P(ret)) { zval_ptr_dtor(&ret); zval_ptr_dtor(&action); return 0; } if (Z_TYPE_P(ret) == IS_STRING && Z_STRLEN_P(ret)) { yaf_response_alter_body(response, NULL, 0, Z_STRVAL_P(ret), Z_STRLEN_P(ret), YAF_RESPONSE_APPEND TSRMLS_CC); } zval_ptr_dtor(&ret); } else { zend_call_method_with_1_params(&executor, ce, NULL, "display", &ret, action); zval_ptr_dtor(&executor); if (!ret) { zval_ptr_dtor(&action); return 0; } if ((Z_TYPE_P(ret) == IS_BOOL && !Z_BVAL_P(ret))) { zval_ptr_dtor(&ret); zval_ptr_dtor(&action); return 0; } zval_ptr_dtor(&ret); } } else { zval_ptr_dtor(&executor); } } zval_ptr_dtor(&action); } return 1; } return 0; }
處理請求之前,yaf_dispatcher_handle函數首先從Request對象讀取路由結果
(module、controller和action)
然後實創建controller對象,執行action定義的邏輯處理請求。需要注意的是,
Yaf編寫Action有兩種方式:
(1)把action方法寫在Controller類中
class Controller_Index extends Yaf_Controller_Abstract {
public function indexAction () {
echo "Hello, World!";
}
}
(2)在Controller對象的$actions保存所有action序對,序對的鍵必須與路由結果的action名字一樣,
而且是小寫,序對的值是action類文件的相對路徑,然後在action類的execute方法中寫處理邏輯。
controllers/Index.php
class Controller_Index extends Yaf_Controller_Abstract { public $actions = array ( 'index' => 'actions/Index.php', ); }
actions/Index.php
class Action_Index extends Yaf_Action_Abstract {
public function execute () {
echo "Hello, World!";
}
}
從源碼中可以看出,Yaf優先從Controller中尋找action方法,如果找到,就執行之,
沒有找到再從Controller中定義的$actions數組中尋找Action類,實例化這個Action類,
並執行其execute方法。
至此,Yaf的請求處理分析差不多了,下一篇文章將會分析Yaf的路由機制。