rustis 0.20.0

Redis async driver for Rust
Documentation 
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use crate::{network::PushReceiver, resp::BulkString};
use futures_util::{Stream, StreamExt};
use std::{
    pin::Pin,
    task::{Context, Poll},
};
use tracing::warn;

pub struct ClientTrackingInvalidationStream {
    receiver: PushReceiver,
}

impl ClientTrackingInvalidationStream {
    pub(crate) fn new(receiver: PushReceiver) -> Self {
        Self { receiver }
    }
}

impl Stream for ClientTrackingInvalidationStream {
    /// Redis keys are binary-safe, hence [`BulkString`] rather than `String`:
    /// a key that is not valid UTF-8 must still reach the consumer.
    type Item = Vec<BulkString>;

    fn poll_next(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>> {
        let this = self.get_mut();

        // An undecodable event must not end the stream: the consumer would stop
        // polling and never learn of another invalidation, leaving every cache
        // built on top of it serving stale data for good. Skip it and keep
        // reading instead.
        loop {
            let Poll::Ready(response) = this.receiver.poll_next_unpin(cx) else {
                return Poll::Pending;
            };

            let Some(response) = response else {
                return Poll::Ready(None);
            };

            match response {
                Ok(response) => match response.to::<((), Vec<BulkString>)>() {
                    Ok((_invalidate, keys)) => return Poll::Ready(Some(keys)),
                    Err(e) => warn!("Cannot decode a client tracking invalidation: {e}"),
                },
                Err(e) => warn!("Error while receiving a client tracking invalidation: {e}"),
            }
        }
    }
}