Trait MetricsObserver 

pub trait MetricsObserver:
    Send
    + Sync
    + 'static {
    // Required method
    fn command_completed(
        &self,
        command: &str,
        in_bytes: usize,
        out_bytes: usize,
        duration: Duration,
        is_error: bool,
    );

    // Provided methods
    fn connection_opened(&self) { ... }
    fn connection_closed(&self) { ... }
    fn connection_refused(&self) { ... }
    fn push_emitted(&self, out_bytes: usize) { ... }
}

Receives one callback per completed command, plus connection lifecycle.

Every method must be cheap and must not block: they run on the connection’s writer task, so time spent here is time the socket is not being written. Anything expensive belongs behind a channel.

Required Methods

fn command_completed( &self, command: &str, in_bytes: usize, out_bytes: usize, duration: Duration, is_error: bool, )

One command completed and its response left the socket.

in_bytes is the request frame size from the decoder and out_bytes the encoded response length — neither is ever re-encoded to be measured (SRV-007). duration is the dispatch time, and is_error reflects the response carrying Err, not a transport failure.

Provided Methods

fn connection_opened(&self)

A connection was accepted.

fn connection_closed(&self)

A connection finished draining and closed.

fn connection_refused(&self)

An accept was refused at the max_connections ceiling.

fn push_emitted(&self, out_bytes: usize)

A server-initiated frame was written (id == PUSH_ID, WIRE-005).

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors