Trait Rmw 

pub trait Rmw {
    type Session: Session;
    type Error: Debug;

    // Required method
    fn open(self, config: &RmwConfig<'_>) -> Result<Self::Session, Self::Error>;
}

Factory trait for compile-time middleware selection.

Embedded crates select a backend via feature flag:

#[cfg(feature = "rmw-cffi")]
type DefaultRmw = nros_rmw_cffi::CffiRmw;

Each backend provides its own Rmw implementation that bridges from the middleware-agnostic RmwConfig to backend-specific initialization.

Phase 84.E2: open consumes self. Backends carry their own configuration (agent addresses, serial ports, TLS CA slots) inside the factory value and hand that over to the session at open time. All in-repo backends also implement Default; most callers spell this as BackendRmw::default().open(&config).

Required Associated Types

type Session: Session

Session type returned by open

type Error: Debug

Error type for session creation

Required Methods

fn open(self, config: &RmwConfig<'_>) -> Result<Self::Session, Self::Error>

Open a new middleware session with the given configuration.

The backend maps RmwConfig fields to its own connection parameters (e.g., zenoh locator and session mode, XRCE-DDS agent address). Any backend-specific pre-open state stored on self (e.g. configured agent IP / port) is moved into the returned Session.

Implementors