Struct SubscribeBuilder 

pub struct SubscribeBuilder<'a> {
    cmd_tx: &'a Sender<Command>,
    filter: TopicFilterBuf,
    qos: QoS,
    no_local: bool,
    retain_as_published: bool,
    retain_handling: RetainHandling,
    subscription_id: Option<u32>,
}

Builder for subscribing to a topic filter with MQTT v5 options.

Obtained via MqttClient::subscribe. Call send to send the SUBSCRIBE packet and await the broker’s SUBACK.

Fields

cmd_tx: &'a Sender<Command>

filter: TopicFilterBuf

qos: QoS

no_local: bool

retain_as_published: bool

retain_handling: RetainHandling

subscription_id: Option<u32>

Implementations

impl<'a> SubscribeBuilder<'a>

pub(crate) const fn new( cmd_tx: &'a Sender<Command>, filter: TopicFilterBuf, ) -> Self

pub const fn qos(self, qos: QoS) -> Self

Set the maximum QoS for messages delivered on this subscription.

pub const fn no_local(self, no_local: bool) -> Self

Set the No Local option (v5): if true, the broker will not forward messages published by this client on matching topics.

pub const fn retain_as_published(self, rap: bool) -> Self

Set the Retain As Published option (v5): if true, the retain flag in forwarded messages reflects the original PUBLISH, not the broker’s retained-message state.

pub const fn retain_handling(self, rh: RetainHandling) -> Self

Set the Retain Handling option (v5): controls when retained messages are sent for this subscription.

pub const fn subscription_id(self, id: u32) -> Self

Assign a Subscription Identifier (v5, property 0x0B).

The broker echoes this identifier in PUBLISH packets that match this subscription. Useful for routing messages to the correct handler.

pub async fn send(self) -> Result<Vec<ReasonCode>, Error>

Send the SUBSCRIBE packet and await the broker’s SUBACK.

Returns the per-filter reason codes from the SUBACK packet.

Errors

Returns Error::ConnectionClosed if the connection is lost before SUBACK arrives.