Struct Publisher 

pub struct Publisher<'a> { /* private fields */ }

A publisher that allows sending data through a stream.

Publishers are automatically undeclared when dropped.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
publisher.put("value").await.unwrap();

Publisher implements the Sink trait which is useful for forwarding streams to zenoh.

use futures::StreamExt;

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let mut subscriber = session.declare_subscriber("key/expression").await.unwrap();
let publisher = session.declare_publisher("another/key/expression").await.unwrap();
subscriber.stream().map(Ok).forward(publisher).await.unwrap();

Implementations

impl<'a> Publisher<'a>

pub fn id(&self) -> EntityGlobalId

Available on crate feature unstable only.

Returns the EntityGlobalId of this Publisher.

This API has been marked as unstable: it works as advertised, but it may be changed in a future release.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let publisher_id = publisher.id();

pub fn key_expr(&self) -> &KeyExpr<'a>

Returns the KeyExpr of this Publisher.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let key_expr = publisher.key_expr();

pub fn encoding(&self) -> &Encoding

Get the Encoding used when publishing data.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let encoding = publisher.encoding();

pub fn congestion_control(&self) -> CongestionControl

Get the CongestionControl applied when routing the data.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let congestion_control = publisher.congestion_control();

pub fn priority(&self) -> Priority

Get the Priority of the written data.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let priority = publisher.priority();

pub fn reliability(&self) -> Reliability

Available on crate feature unstable only.

Get the Reliability applied when routing the data.

This API has been marked as unstable: it works as advertised, but it may be changed in a future release.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression")
    .await
    .unwrap();
let reliability = publisher.reliability();

pub fn put<IntoZBytes>(&self, payload: IntoZBytes) -> PublisherPutBuilder<'_>

where IntoZBytes: Into<ZBytes>,

Publish the data. The subscribers matching the Publisher’s key expression will receive the Sample with kind SampleKind::Put.

The builder allows customizing the publication: add the timestamp, attachment, etc. Some fields are pre-filled with the Publisher’s configuration and can be overridden.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
publisher.put("value").await.unwrap();

pub fn delete(&self) -> PublisherDeleteBuilder<'_>

Declare that the data associated with the Publisher’s key expression is deleted. The subscribers will receive the Sample with kind SampleKind::Delete.

The builder allows customizing the publication: add the timestamp, attachment, etc.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
publisher.delete().await.unwrap();

pub fn matching_status(&self) -> impl Resolve<ZResult<MatchingStatus>> + '_

Return the MatchingStatus of the publisher.

MatchingStatus::matching will return true if there exist Subscribers matching the Publisher’s key expression and false otherwise.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
let matching_subscribers: bool = publisher
    .matching_status()
    .await
    .unwrap()
    .matching();

pub fn matching_listener(&self) -> MatchingListenerBuilder<'_, DefaultHandler>

Return a MatchingListener for this Publisher.

The MatchingListener will send a notification each time the MatchingStatus of the Publisher changes.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
let matching_listener = publisher.matching_listener().await.unwrap();
while let Ok(matching_status) = matching_listener.recv_async().await {
    if matching_status.matching() {
        println!("Publisher has matching subscribers.");
    } else {
        println!("Publisher has NO MORE matching subscribers.");
    }
}

pub fn undeclare(self) -> impl Resolve<ZResult<()>> + 'a

Undeclare the Publisher, informing the network that it needn’t optimize publications for its key expression anymore.

Examples

let session = zenoh::open(zenoh::Config::default()).await.unwrap();
let publisher = session.declare_publisher("key/expression").await.unwrap();
publisher.undeclare().await.unwrap();

Trait Implementations

impl<'a> Debug for Publisher<'a>

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

Formats the value using the given formatter.

impl Drop for Publisher<'_>

fn drop(&mut self)

Executes the destructor for this type.

impl Sink<Sample> for Publisher<'_>

type Error = Box<dyn Error + Send + Sync>

The type of value produced by the sink when an error occurs.

fn poll_ready( self: Pin<&mut Self>, _cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Attempts to prepare the Sink to receive a value.

fn start_send(self: Pin<&mut Self>, item: Sample) -> Result<(), Self::Error>

Begin the process of sending a value to the sink. Each call to this function must be preceded by a successful call to poll_ready which returned Poll::Ready(Ok(())).

fn poll_flush( self: Pin<&mut Self>, _cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Flush any remaining output from this sink.

fn poll_close( self: Pin<&mut Self>, _cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Flush any remaining output and close this sink, if necessary.