drogon跨域问题和全局异常处理

2024年6月20日12:21:11

在main.cc里加入

 /**
     * 全局异常处理
     */
    drogon::app().setExceptionHandler([](
                                          const std::exception &e,
                                          const drogon::HttpRequestPtr &req,
                                          std::function<void(drogon::HttpResponsePtr &)> &&callback)
                                      {

        LOG_DEBUG << e.what();

        Json::Value json;
        json["code"] = FAIL;
        json["error"] = e.what();
        json["data"] = "";
        auto resp = drogon::HttpResponse::newHttpJsonResponse(json);
        callback(resp); });

    // 跨域
    drogon::app().registerSyncAdvice([](const drogon::HttpRequestPtr &req) -> drogon::HttpResponsePtr
                                     {
			if(req->method() == drogon::HttpMethod::Options)
			{
				auto resp = drogon::HttpResponse::newHttpResponse();
				{
					const auto& val = req->getHeader("Origin");
					if(!val.empty())
						resp->addHeader("Access-Control-Allow-Origin", val);
				}
				{
					const auto& val = req->getHeader("Access-Control-Request-Method");
					if(!val.empty())
						resp->addHeader("Access-Control-Allow-Methods", val);
				}
				resp->addHeader("Access-Control-Allow-Credentials", "true");
				{
					const auto& val = req->getHeader("Access-Control-Request-Headers");
					if(!val.empty())
						resp->addHeader("Access-Control-Allow-Headers", val);
				}
				return std::move(resp);
			}
			return {}; })
        .registerPostHandlingAdvice([](const drogon::HttpRequestPtr &req, const drogon::HttpResponsePtr &resp) -> void
                                    {
			{
				const auto& val = req->getHeader("Origin");
				if(!val.empty())
					resp->addHeader("Access-Control-Allow-Origin", val);
			}
			{
				const auto& val = req->getHeader("Access-Control-Request-Method");
				if(!val.empty())
					resp->addHeader("Access-Control-Allow-Methods", val);
			}
			resp->addHeader("Access-Control-Allow-Credentials", "true");
			{
				const auto& val = req->getHeader("Access-Control-Request-Headers");
				if(!val.empty())
					resp->addHeader("Access-Control-Allow-Headers", val);
			} })
        .run();

路由上得加上 options
 ADD_METHOD_TO(IndexController::getMenu, "/api/admin/getMenu", Options, Post, "LoginFilter");       // 获取菜单
		
下图显示了的位置，http请求处理期间的AOP连接点。
		
                         +-----------+                             +----------+
                         |  Request  |                             | Response |
                         +-----------+                             +----------+
                               |                                         ^
                               v                                         |
               sync join point o----------->[HttpResponsePtr]----------->+
                               |                                         |
                               v                                         |
        Pre-routing join point o----------->[Advice callback]----------->+
                               |                                         |
                               v         Invalid path                    |
                         [Find Handler]---------------->[404]----------->+
                               |                                         |
                               v                                         |
       Post-routing join point o----------->[Advice callback]----------->+
                               |                                         |
                               v        Invalid method                   |
                         [Check Method]---------------->[405]----------->+
                               |                                         |
                               v                                         |
                           [Filters]------->[Filter callback]----------->+
                               |                                         |
                               v             Y                           |
                      [Is OPTIONS method?]------------->[200]----------->+
                               |                                         |
                               v                                         |
       Pre-handling join point o----------->[Advice callback]----------->+
                               |                                         |
                               v                                         |
                           [Handler]                                     |
                               |                                         |
                               v                                         |
      Post-handling join point o---------------------------------------->+


      app.registerHttpSimpleController("/userinfo","UserInfoCtrl",{Get,"LoginFilter"});

刚开始只写了 registerPostHandlingAdvice的处理发下不行，然后参看看
https://github.com/drogonframework/drogon/issues/2014

发现还要增加 registerSyncAdvice去单独处理 Options，才行，如果你在nginx做了跨域处理，还是不行的，本地测试还是有跨域问题