xmlrpc-proc

A procedural macro to generate typed method calls for a remote rpc endpoint using xmlrpc.

Why

A rpc call using the crate xmlrpc is required to use the builder pattern with "untyped" arguments, like this from their sample:

let pow_request = Request::new("pow").arg(2).arg(8); // Compute 2**8
let request_result = pow_request.call_url("http://127.0.0.1:8000");

With this procedural macro, you can define the remote methods as a Rust trait, and take advantage of compiler help to identify and avoid passing wrong arguments to the remote call. We could then define the remote interface this way:

#[xmlrpc(RemoteServer)]
trait RemoteApi {
    fn pow(&self, val: i32, power: i32) -> Result<Value, Error>;
}

which will generate:

impl RemoteApi for RemoteServer {
    fn pow(&self, val: i32, power: i32) -> Result<Value, Error> {
        let req = Request::new("pow").arg(val).arg(power);
        req.call_url(&self.endpoint)
    }
}

And using it would become as simple as a rust method call:

let request_result = server.pow(2, 8);

For a complete example, see the xmlrpc-sample

TODO

• Automatic result conversion to primitives or user types
  • i.e. Result<Value, Error> to Result<User, Error> where User is a local struct.