C++: Application architecture with API

Question

My application it's C++ service. And I need to add API for it. I consider that it will be XML/JSON RPC based API. How should I design a program for reusing existing code base and provide API.

I see following options:

1. My application will work via RPC layer. Seems that it's bad option due to low performance;
2. Before starting of service I will fork it and run my application in the first process and RPC server in the second; Seems ok, but how to restart RPC server in this case?
3. I guess there is a well known pattern for such issues.

Thanks.

Answer 1

If you can use a web server, then the FastCGI concept might be what you're looking for. One of the main duties of FastCGI is to allow you to put on a public API (from the web server) that internally calls the "real" application, in your case the resident C++ service. So all work is done at the web server to create the public API using any technology you wish, and little or no code changes done in your C++ service.