Function route_from_expose 

pub async fn route_from_expose<C, V>(
    expose: RouteBundle<ExposeDecl>,
    expose_target: Arc<C>,
    sources: Sources,
    visitor: &mut V,
    mapper: &mut dyn DebugRouteMapper,
) -> Result<CapabilitySource, RoutingError>
where
    C: ComponentInstanceInterface + 'static,
    V: OfferVisitor + ExposeVisitor + CapabilityVisitor + Clone + Send + Sync + 'static,

Routes a capability from its Expose declaration to its source by following Expose declarations.

sources defines what are the valid sources of the capability. See Sources. visitor is invoked for each Expose declaration in the routing path, as well as the final Capability declaration if sources permits.