Struct Will 

pub struct Will { /* private fields */ }

A message the broker publishes on the client’s behalf if the client’s connection ends without a DISCONNECT: the network dropped, the power failed, or the keep-alive ran out.

A device that publishes online to a status topic when it connects usually leaves a will of offline on the same topic, retained, so anyone watching sees it go (OASIS MQTT 3.1.1, section 3.1.2.5). A client that disconnects on purpose leaves no will behind.

Examples

use pamoja_mqtt::{MqttConfig, QualityOfService, Will};

let will = Will::new("sites/pump-3/status", b"offline")
    .qos(QualityOfService::AtLeastOnce)
    .retained();
let config = MqttConfig::new("pump-3", "localhost", 1883).last_will(will);
assert_eq!(config.will().map(Will::topic), Some("sites/pump-3/status"));

Implementations

impl Will

pub fn new(topic: impl Into<String>, payload: impl Into<Vec<u8>>) -> Will

Creates a will to publish to a topic, at QoS 0 and not retained.

Arguments

• topic - where the broker publishes it; a topic name, with no wildcard.
• payload - what it publishes.

Returns

The will.

pub fn qos(self, qos: QualityOfService) -> Will

Sets the quality of service the broker publishes the will at.

Arguments

• qos - the delivery guarantee.

Returns

The updated will, for chaining.

pub fn retained(self) -> Will

Has the broker retain the will, so a client that subscribes later still sees it.

Returns

The updated will, for chaining.

pub fn topic(&self) -> &str

Returns the topic the will is published to.

Returns

The topic.

pub fn payload(&self) -> &[u8]

Returns what the will publishes.

Returns

The payload.

pub fn quality_of_service(&self) -> QualityOfService

Returns the quality of service the will is published at.

Returns

The delivery guarantee.

pub fn is_retained(&self) -> bool

Returns whether the broker retains the will.

Returns

true for a retained will.

Trait Implementations

impl Clone for Will

fn clone(&self) -> Will

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Will

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

Formats the value using the given formatter.

impl Eq for Will

impl PartialEq for Will

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Will