Enum SessionOpenError 

pub(crate) enum SessionOpenError {
    DeviceNotFound(String),
    Transient(String),
    Aborted,
}

Why a session failed to open: drives the retry policy of the caller.

Variants

DeviceNotFound(String)

The named source is absent at startup (misconfiguration-ish); the caller gives it only its short bring-up window rather than the full startup retry budget.

Transient(String)

Server down, busy, or a bring-up race: retryable.

Aborted

stop_pending observed while opening; caller must shut down cleanly.