class MyClass:public drogon::HttpSimpleController<MyClass>
public:
    //TestController(){}
    virtual void asyncHandleHttpRequest(const HttpRequestPtr &req,
                                         std::function<void (const HttpResponsePtr &)> &&callback) override;
    PATH_LIST_BEGIN
    PATH_ADD("/json");
    PATH_LIST_END
};

Controller life cycle

04.1 HttpSimpleController