Type Alias Middleware 

pub type Middleware = Arc<dyn for<'a> Fn(&'a mut CorrelationContext) -> BoxFuture<'a, Result<(), ErrorResult>> + Send + Sync>;

Pre-handler hook: inspects or mutates the context and headers, returning Ok(()) to continue or Err(ErrorResult) to short-circuit with an error response.

Aliased Type

pub struct Middleware { /* private fields */ }