Enum ConnectionState 

#[non_exhaustive]
pub enum ConnectionState {
    #[non_exhaustive]
    Connected {
        session_present: bool,
    },
    #[non_exhaustive]
    Reconnecting {
        attempt: u32,
    },
    #[non_exhaustive]
    Disconnected {
        reason: DisconnectReason,
    },
}

The connection’s current lifecycle state.

Designed v5-first: every variant is #[non_exhaustive] so protocol-5 fields (reason codes, properties) can be added without a breaking change.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

#[non_exhaustive]

Connected

The connection is up. session_present reports whether the broker resumed an existing session (v4 CONNACK today; v5 CONNACK identically later) — false means a clean session, so subscriptions were re-established by the client.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

session_present: bool

Broker resumed a prior session rather than starting a clean one.

#[non_exhaustive]

Reconnecting

The connection was lost and the backend is retrying. attempt is the number of consecutive poll failures since the last successful poll; it resets to 0 on any success (a reconnect, a delivered message, or another notification). It is tracked separately from the internal error counter that drives backoff and DisconnectReason::MaxErrorsExceeded, so a broker that keeps reconnecting is not permanently killed yet a truly unreachable broker still terminates.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

attempt: u32

Consecutive poll failures since the last successful poll.

#[non_exhaustive]

Disconnected

Terminal. The event loop has exited; no further transitions occur and every subscriber’s receive() now yields None.

Fields

Non-exhaustive enum variants could have additional fields added in future. Therefore, non-exhaustive enum variants cannot be constructed in external crates and cannot be matched against.

reason: DisconnectReason

Why the event loop terminated.

Trait Implementations

impl Clone for ConnectionState

fn clone(&self) -> ConnectionState

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ConnectionState

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for ConnectionState

impl PartialEq for ConnectionState

fn eq(&self, other: &ConnectionState) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ConnectionState