Struct Tracker

pub struct Tracker { /* private fields */ }

A registry of subscription streams.

If you have an application that continuously returns a Subscription, you can use a Tracker to keep track of the different recipes and keep its executions alive.

Implementations

impl Tracker

pub fn new() -> Self

Creates a new empty Tracker.

pub fn update<Message, Receiver>( &mut self, recipes: impl Iterator<Item = Box<dyn Recipe<Output = Message>>>, receiver: Receiver, ) -> Vec<BoxFuture<()>>

where Message: 'static + MaybeSend, Receiver: 'static + Sink<Message, Error = SendError> + Unpin + MaybeSend + Clone,

Updates the Tracker with the given Subscription.

A Subscription can cause new streams to be spawned or old streams to be closed.

The Tracker keeps track of these streams between calls to this method:

• If the provided Subscription contains a new Recipe that is currently not being run, it will spawn a new stream and keep it alive.
• On the other hand, if a Recipe is currently in execution and the provided Subscription does not contain it anymore, then the Tracker will close and drop the relevant stream.

It returns a list of futures that need to be spawned to materialize the Tracker changes.

pub fn broadcast(&mut self, event: Event)

Broadcasts an event to the subscriptions currently alive.

A subscription’s Recipe::stream always receives a stream of events as input. This stream can be used by some subscription to listen to shell events.

This method publishes the given event to all the subscription streams currently open.

Trait Implementations

impl Debug for Tracker

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

Formats the value using the given formatter.

impl Default for Tracker

fn default() -> Tracker

Returns the “default value” for a type.