xandris / castor

Gemini server in C++20

Castor Gemini Server

Goal: A Gemini protocol server in C++20 using boost::asio and coroutines.

The last time I used C++ was over 20 years ago, so I'm hoping for a useful end product and to learn modern C++.

I'm still getting started, so don't expect a functioning server yet!

Very modest roadmap

• Open a listening socket

• Accept a connection

• Do an SSL handshake on the socket

• Read a line of input

• Clean up resources automatically

• Handle signals

• Parse a URL

• Define a request

• Define a response

  It would be nice to have behavior similar to Java's ServletResponse; send the header on the first write to the output stream.

  Or... a handler can return a body. Like a string for a simple body, or a std::istream for something on the filesystem. A stream in boost::asio is a concept, not a type, so different kinds of streams are unrelated types.

  As long the body meets the AsyncReadStream requirements, it should work. Then we can implement a polymorphic system where StreamBody<AsyncReadStream T> is-a Body. Not very sexy though.

• Define a handler

• Bind handlers to URLs

• Make a filesystem handler

• Define middleware

• Process middleware

• Set "acceptable CAs" for the handshake

• Get the client certificate from the handshake