roscpp: How to get ROS service type from string?

Question

Is it possible to get service type from name of the service or from a service type string? I would want something like this:

string srv_name = "foo";
string srv_type = "std_srvs/SetBool";
auto request = getSrvType(srv_type)::Request;
// or
auto request = getSrvType(srv_name)::Request;