Method initialize

3rdparty/libprocess/examples/example.cpp:69–81

protected:
  void initialize() override
  {
    // route("/vars", None(), &MyProcess::vars);
    route("/vars", None(), [=](const Request& request) {
      string body = "... vars here ...";
      return OK(body);
    });

    // install("stop", &MyProcess::stop);
    install("stop", [=](const UPID& from, const string& body) {
      terminate(self());
    });
  }

private:
  Promise<int> promise;