Enum QoS

pub enum QoS {
    AtMostOnce = 0,
    AtLeastOnce = 1,
    ExactlyOnce = 2,
}

The maximum Quality of Service used to transmit and receive messages.

If the value used to publish a message is different than the value used to subscribe to its corresponding topic, the effective quality of service will be the lowest of these.

Variants

AtMostOnce = 0

Messages will be transmitted or received at most once.

This is the lowest (but fastest) quality of service, involving a single packet. However, it is possible that the message may never be transmitted or received.

AtLeastOnce = 1

Messages will be transmitted or received at least once.

This quality of service involves at least 2 packets. Using this value as the effective quality of service means that messages will definitely be received by the recipient(s), but they may receive multiple copies of it.

ExactlyOnce = 2

Messages will be transmitted or received exactly once.

This is the highest (but slowest) quality of service, involving at least 4 packets. However, if used as the effective quality of service, it ensures that the packet will be received by recipient(s) without any duplicates.

Trait Implementations

impl Clone for QoS

fn clone(&self) -> QoS

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for QoS

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

Formats the value using the given formatter.

impl Ord for QoS

fn cmp(&self, other: &QoS) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for QoS

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for QoS

fn partial_cmp(&self, other: &QoS) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for QoS

impl Eq for QoS

impl StructuralPartialEq for QoS