This is a example echo server in Rust, that shows how to implement switchable transport using generics.
With generics, there is no runtime cost of dynamical dispatch, but it results in a larger binary. It's also less flexible.
Other approachs to achieve switchable transport layer are enum_dispatch and dynamical dispatch using Box and dyn. These methods are easier to implement, but all come with runtime cost.
Hopefully you can find this helpful :)
Run the server in TLS
cargo run -- tls server
# In a new terminal
cargo run -- tls client
Run the server in TCP
cargo run -- tcp server
# In a new terminal
cargo run -- tcp client
They use the same code, but different transport layers!
async fn send_hello<T: Transport>(transport: T) -> Result<()> {
let mut conn = transport.connect(&String::from("127.0.0.1:2334")).await?;
let req = "hello";
conn.write_all(req.as_bytes()).await?;
io::copy(&mut conn, &mut io::stdout()).await?;
Ok(())
}Don't ever use the come-along certifacte in production! It's just for the presentation.