Struct StreamRetry

pub struct StreamRetry<F, S> { /* private fields */ }

Provides a way to handle errors during a Stream execution, i.e. it gives you an ability to poll for future stream’s items with a delay.

This type is similar to FutureRetry, but with a different semantics. For example, if for FutureRetry we need a factory that creates Futures, we don’t need one for Streams, since Stream itself is a natural producer of new items, so we don’t have to recreated it if an error is encountered.

A typical usage might be recovering from connection errors while trying to accept a connection on a TCP server.

A tcp-listener example is available in the examples folder.

Also have a look at StreamRetryExt trait for a more convenient usage.

Implementations

impl<F, S> StreamRetry<F, S>

pub fn new(stream: S, error_action: F) -> Self

where S: TryStream,

Creates a StreamRetry using a provided stream and an object of ErrorHandler type that decides on a retry-policy depending on an encountered error.

Please refer to the tcp-listener example in the examples folder to have a look at a possible usage or to a very convenient extension trait StreamRetryExt.

Arguments

• stream: a stream of future items,
• error_action: a type that handles an error and decides which route to take: simply try again, wait and then try, or give up (on a critical error for exapmle).

pub fn with_counter(stream: S, error_action: F, attempt_counter: usize) -> Self

Like a new method, but a custom attempt counter initial value might be provided.

Trait Implementations

impl<F, S> Stream for StreamRetry<F, S>

where S: TryStream, F: ErrorHandler<S::Error>,

type Item = Result<(<S as TryStream>::Ok, usize), (<F as ErrorHandler<<S as TryStream>::Error>>::OutError, usize)>

Values yielded by the stream.

fn poll_next( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Option<Self::Item>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.

impl<'__pin, F, S> Unpin for StreamRetry<F, S>

where __Origin<'__pin, F, S>: Unpin,