Struct ServiceResolverBuilder 

pub struct ServiceResolverBuilder { /* private fields */ }

Builder for a one-shot DNS-SD resolve of a single, already-known service instance.

Where ServiceBrowserBuilder discovers instances over time, this resolves one named instance now — mapping the identity fields from a previous browse BrowseEvent::Found (or BrowseEvent::Removed) event back to a connectable DiscoveredService. Its main use is as a liveness probe: a dead instance fails with ServiceBrowseError::ResolveFailed rather than hanging, so consumers can re-confirm services they haven’t heard from recently and drop the ones that repeatedly fail.

This matters for the no-goodbye case (a host powered off, crashed, or that dropped off Wi-Fi without multicasting mDNS goodbye packets): the OS keeps the browse-driving PTR record until its (long) TTL expires, so no Removed event is delivered for a long time, yet a fresh resolve of the vanished instance fails promptly.

Example

use mdns_sd_discovery::{ServiceBrowseError, ServiceResolverBuilder};

match ServiceResolverBuilder::new("My Web Server", "_http._tcp", "local")
    .resolve()
    .await
{
    Ok(svc) => println!("still alive at {}:{}", svc.host_name, svc.port),
    Err(ServiceBrowseError::ResolveFailed(name, _)) => println!("{name} is gone"),
    Err(err) => return Err(err.into()),
}

Implementations

impl ServiceResolverBuilder

pub fn new( name: impl AsRef<str>, service_type: impl AsRef<str>, domain: impl AsRef<str>, ) -> Self

Initializes a builder to resolve the instance identified by name, service_type (e.g. _http._tcp) and domain (e.g. local).

These are exactly the name, service_type and domain fields reported by a browse event.

pub fn interface_index(&mut self, index: NonZeroU32) -> &mut Self

Restricts the resolve to a single interface (the index reported on the originating browse event, via DiscoveredService::interface_index).

When unset (the default) the instance is resolved on all interfaces.

pub fn timeout(&mut self, timeout: Duration) -> &mut Self

Bounds how long resolve may take before failing with ServiceBrowseError::ResolveFailed.

This is what makes the resolve usable as a liveness probe: without it, resolving a vanished instance is only bounded by the platform default (on Linux, the D-Bus method timeout of roughly 25 s). Set a shorter timeout to fail faster; the platform default still applies as a ceiling.

pub async fn resolve(&self) -> Result<DiscoveredService, ServiceBrowseError>

Resolves the instance, returning a connectable DiscoveredService.

Returns ServiceBrowseError::ResolveFailed if the instance no longer responds (or the configured timeout elapses first).

Trait Implementations

impl Clone for ServiceResolverBuilder

fn clone(&self) -> ServiceResolverBuilder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ServiceResolverBuilder

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

Formats the value using the given formatter.