Struct tower::util::CallAll[][src]

pub struct CallAll<Svc, S> where
    Svc: Service<S::Item>,
    S: Stream
{ /* fields omitted */ }
This is supported on crate feature util only.
Expand description

This is a Stream of responses resulting from calling the wrapped Service for each request received on the wrapped Stream.

use futures::future::{ready, Ready};
use futures::StreamExt;
use futures::channel::mpsc;
use tower_service::Service;
use tower::util::ServiceExt;

// First, we need to have a Service to process our requests.
#[derive(Debug, Eq, PartialEq)]
struct FirstLetter;
impl Service<&'static str> for FirstLetter {
     type Response = &'static str;
     type Error = Box<dyn Error + Send + Sync>;
     type Future = Ready<Result<Self::Response, Self::Error>>;

     fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
         Poll::Ready(Ok(()))
     }

     fn call(&mut self, req: &'static str) -> Self::Future {
         ready(Ok(&req[..1]))
     }
}

#[tokio::main]
async fn main() {
    // Next, we need a Stream of requests.
    let (mut reqs, rx) = mpsc::unbounded();
    // Note that we have to help Rust out here by telling it what error type to use.
    // Specifically, it has to be From<Service::Error> + From<Stream::Error>.
    let mut rsps = FirstLetter.call_all(rx);

    // Now, let's send a few requests and then check that we get the corresponding responses.
    reqs.unbounded_send("one").unwrap();
    reqs.unbounded_send("two").unwrap();
    reqs.unbounded_send("three").unwrap();
    drop(reqs);

    // We then loop over the response Strem that we get back from call_all.
    let mut i = 0usize;
    while let Some(rsp) = rsps.next().await {
        // Each response is a Result (we could also have used TryStream::try_next)
        match (i + 1, rsp.unwrap()) {
            (1, "o") |
            (2, "t") |
            (3, "t") => {}
            (n, i) => {
                unreachable!("{}. response was '{}'", n, i);
            }
        }
        i += 1;
    }

    // And at the end, we can get the Service back when there are no more requests.
    assert_eq!(rsps.into_inner(), FirstLetter);
}

Implementations

impl<Svc, S> CallAll<Svc, S> where
    Svc: Service<S::Item>,
    Svc::Error: Into<BoxError>,
    S: Stream
[src]

pub fn new(service: Svc, stream: S) -> CallAll<Svc, S>[src]

Create new CallAll combinator.

Each request yielded by stream is passed to svc, and the resulting responses are yielded in the same order by the implementation of Stream for CallAll.

pub fn into_inner(self) -> Svc[src]

Extract the wrapped Service.

Panics

Panics if take_service was already called.

pub fn take_service(self: Pin<&mut Self>) -> Svc[src]

Extract the wrapped Service.

This CallAll can no longer be used after this function has been called.

Panics

Panics if take_service was already called.

pub fn unordered(self) -> CallAllUnordered<Svc, S>[src]

Return responses as they are ready, regardless of the initial order.

This function must be called before the stream is polled.

Panics

Panics if poll was called.

Trait Implementations

impl<Svc: Debug, S: Debug> Debug for CallAll<Svc, S> where
    Svc: Service<S::Item>,
    S: Stream,
    Svc::Future: Debug
[src]

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

Formats the value using the given formatter. Read more

impl<Svc, S> Stream for CallAll<Svc, S> where
    Svc: Service<S::Item>,
    Svc::Error: Into<BoxError>,
    S: Stream
[src]

type Item = Result<Svc::Response, BoxError>

Values yielded by the stream.

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

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. Read more

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

Returns the bounds on the remaining length of the stream. Read more

impl<'pin, Svc, S> Unpin for CallAll<Svc, S> where
    Svc: Service<S::Item>,
    S: Stream,
    __CallAll<'pin, Svc, S>: Unpin
[src]

Auto Trait Implementations

impl<Svc, S> !RefUnwindSafe for CallAll<Svc, S>

impl<Svc, S> Send for CallAll<Svc, S> where
    S: Send,
    Svc: Send,
    <Svc as Service<<S as Stream>::Item>>::Error: Send,
    <Svc as Service<<S as Stream>::Item>>::Future: Send,
    <Svc as Service<<S as Stream>::Item>>::Response: Send

impl<Svc, S> Sync for CallAll<Svc, S> where
    S: Sync,
    Svc: Sync,
    <Svc as Service<<S as Stream>::Item>>::Error: Sync,
    <Svc as Service<<S as Stream>::Item>>::Future: Sync,
    <Svc as Service<<S as Stream>::Item>>::Response: Sync

impl<Svc, S> !UnwindSafe for CallAll<Svc, S>

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

pub fn type_id(&self) -> TypeId[src]

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

pub fn borrow(&self) -> &T[src]

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

pub fn borrow_mut(&mut self) -> &mut T[src]

Mutably borrows from an owned value. Read more

impl<K, S, E, D> Discover for D where
    D: TryStream<Ok = Change<K, S>, Error = E> + ?Sized,
    K: Eq
[src]

type Key = K

This is supported on crate feature discover only.

A unique identifier for each active service. Read more

type Service = S

This is supported on crate feature discover only.

The type of Service yielded by this Discover. Read more

type Error = E

This is supported on crate feature discover only.

Error produced during discovery

pub fn poll_discover(
    Pin<&mut D>,
    &mut Context<'_>
) -> Poll<Option<Result<<D as TryStream>::Ok, <D as TryStream>::Error>>>
[src]

This is supported on crate feature discover only.

Yields the next discovery change set.

impl<T> From<T> for T[src]

pub fn from(t: T) -> T[src]

Performs the conversion.

impl<T> Instrument for T[src]

fn instrument(self, span: Span) -> Instrumented<Self>[src]

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

fn in_current_span(self) -> Instrumented<Self>[src]

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

pub fn into(self) -> U[src]

Performs the conversion.

impl<T> StreamExt for T where
    T: Stream + ?Sized
[src]

fn next(&mut self) -> Next<'_, Self> where
    Self: Unpin
[src]

Creates a future that resolves to the next item in the stream. Read more

fn into_future(self) -> StreamFuture<Self> where
    Self: Unpin
[src]

Converts this stream into a future of (next_item, tail_of_stream). If the stream terminates, then the next item is None. Read more

fn map<T, F>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> T, 
[src]

Maps this stream’s items to a different type, returning a new stream of the resulting type. Read more

fn enumerate(self) -> Enumerate<Self>[src]

Creates a stream which gives the current iteration count as well as the next value. Read more

fn filter<Fut, F>(self, f: F) -> Filter<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>, 
[src]

Filters the values produced by this stream according to the provided asynchronous predicate. Read more

fn filter_map<Fut, T, F>(self, f: F) -> FilterMap<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = Option<T>>, 
[src]

Filters the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more

fn then<Fut, F>(self, f: F) -> Then<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future
[src]

Computes from this stream’s items new items of a different type using an asynchronous closure. Read more

fn collect<C>(self) -> Collect<Self, C> where
    C: Default + Extend<Self::Item>, 
[src]

Transforms a stream into a collection, returning a future representing the result of that computation. Read more

fn unzip<A, B, FromA, FromB>(self) -> Unzip<Self, FromA, FromB> where
    Self: Stream<Item = (A, B)>,
    FromA: Default + Extend<A>,
    FromB: Default + Extend<B>, 
[src]

Converts a stream of pairs into a future, which resolves to pair of containers. Read more

fn concat(self) -> Concat<Self> where
    Self::Item: Extend<<Self::Item as IntoIterator>::Item>,
    Self::Item: IntoIterator,
    Self::Item: Default
[src]

Concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more

fn cycle(self) -> Cycle<Self> where
    Self: Clone
[src]

Repeats a stream endlessly. Read more

fn fold<T, Fut, F>(self, init: T, f: F) -> Fold<Self, Fut, T, F> where
    F: FnMut(T, Self::Item) -> Fut,
    Fut: Future<Output = T>, 
[src]

Execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more

fn flatten(self) -> Flatten<Self> where
    Self::Item: Stream
[src]

Flattens a stream of streams into just one continuous stream. Read more

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
    F: FnMut(Self::Item) -> U,
    U: Stream
[src]

Maps a stream like StreamExt::map but flattens nested Streams. Read more

fn scan<S, B, Fut, F>(self, initial_state: S, f: F) -> Scan<Self, S, Fut, F> where
    F: FnMut(&mut S, Self::Item) -> Fut,
    Fut: Future<Output = Option<B>>, 
[src]

Combinator similar to StreamExt::fold that holds internal state and produces a new stream. Read more

fn skip_while<Fut, F>(self, f: F) -> SkipWhile<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>, 
[src]

Skip elements on this stream while the provided asynchronous predicate resolves to true. Read more

fn take_while<Fut, F>(self, f: F) -> TakeWhile<Self, Fut, F> where
    F: FnMut(&Self::Item) -> Fut,
    Fut: Future<Output = bool>, 
[src]

Take elements from this stream while the provided asynchronous predicate resolves to true. Read more

fn take_until<Fut>(self, fut: Fut) -> TakeUntil<Self, Fut> where
    Fut: Future
[src]

Take elements from this stream until the provided future resolves. Read more

fn for_each<Fut, F>(self, f: F) -> ForEach<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = ()>, 
[src]

Runs this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more

fn for_each_concurrent<Fut, F>(
    self,
    limit: impl Into<Option<usize>>,
    f: F
) -> ForEachConcurrent<Self, Fut, F> where
    F: FnMut(Self::Item) -> Fut,
    Fut: Future<Output = ()>, 
[src]

Runs this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available. Read more

fn take(self, n: usize) -> Take<Self>[src]

Creates a new stream of at most n items of the underlying stream. Read more

fn skip(self, n: usize) -> Skip<Self>[src]

Creates a new stream which skips n items of the underlying stream. Read more

fn fuse(self) -> Fuse<Self>[src]

Fuse a stream such that poll_next will never again be called once it has finished. This method can be used to turn any Stream into a FusedStream. Read more

fn by_ref(&mut self) -> &mut Self[src]

Borrows a stream, rather than consuming it. Read more

fn catch_unwind(self) -> CatchUnwind<Self> where
    Self: UnwindSafe
[src]

Catches unwinding panics while polling the stream. Read more

fn boxed<'a>(
    self
) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a + Send, Global>> where
    Self: Send + 'a, 
[src]

Wrap the stream in a Box, pinning it. Read more

fn boxed_local<'a>(self) -> Pin<Box<dyn Stream<Item = Self::Item> + 'a, Global>> where
    Self: 'a, 
[src]

Wrap the stream in a Box, pinning it. Read more

fn buffered(self, n: usize) -> Buffered<Self> where
    Self::Item: Future
[src]

An adaptor for creating a buffered list of pending futures. Read more

fn buffer_unordered(self, n: usize) -> BufferUnordered<Self> where
    Self::Item: Future
[src]

An adaptor for creating a buffered list of pending futures (unordered). Read more

fn zip<St>(self, other: St) -> Zip<Self, St> where
    St: Stream
[src]

An adapter for zipping two streams together. Read more

fn chain<St>(self, other: St) -> Chain<Self, St> where
    St: Stream<Item = Self::Item>, 
[src]

Adapter for chaining two streams. Read more

fn peekable(self) -> Peekable<Self>[src]

Creates a new stream which exposes a peek method. Read more

fn chunks(self, capacity: usize) -> Chunks<Self>[src]

An adaptor for chunking up items of the stream inside a vector. Read more

fn ready_chunks(self, capacity: usize) -> ReadyChunks<Self>[src]

An adaptor for chunking up ready items of the stream inside a vector. Read more

fn forward<S>(self, sink: S) -> Forward<Self, S> where
    Self: TryStream,
    S: Sink<Self::Ok, Error = Self::Error>, 
[src]

A future that completes after the given stream has been fully processed into the sink and the sink has been flushed and closed. Read more

fn split<Item>(self) -> (SplitSink<Self, Item>, SplitStream<Self>) where
    Self: Sink<Item>, 
[src]

Splits this Stream + Sink object into separate Sink and Stream objects. Read more

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnMut(&Self::Item), 
[src]

Do something with each item of this stream, afterwards passing it on. Read more

fn left_stream<B>(self) -> Either<Self, B> where
    B: Stream<Item = Self::Item>, 
[src]

Wrap this stream in an Either stream, making it the left-hand variant of that Either. Read more

fn right_stream<B>(self) -> Either<B, Self> where
    B: Stream<Item = Self::Item>, 
[src]

Wrap this stream in an Either stream, making it the right-hand variant of that Either. Read more

fn poll_next_unpin(&mut self, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> where
    Self: Unpin
[src]

A convenience method for calling Stream::poll_next on Unpin stream types. Read more

fn select_next_some(&mut self) -> SelectNextSome<'_, Self> where
    Self: Unpin + FusedStream
[src]

Returns a Future that resolves when the next item in this stream is ready. Read more

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]

Performs the conversion.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]

Performs the conversion.

impl<S, T, E> TryStream for S where
    S: Stream<Item = Result<T, E>> + ?Sized
[src]

type Ok = T

The type of successful values yielded by this future

type Error = E

The type of failures yielded by this future

pub fn try_poll_next(
    self: Pin<&mut S>,
    cx: &mut Context<'_>
) -> Poll<Option<Result<<S as TryStream>::Ok, <S as TryStream>::Error>>>
[src]

Poll this TryStream as if it were a Stream. Read more

impl<S> TryStreamExt for S where
    S: TryStream + ?Sized
[src]

fn err_into<E>(self) -> ErrInto<Self, E> where
    Self::Error: Into<E>, 
[src]

Wraps the current stream in a new stream which converts the error type into the one provided. Read more

fn map_ok<T, F>(self, f: F) -> MapOk<Self, F> where
    F: FnMut(Self::Ok) -> T, 
[src]

Wraps the current stream in a new stream which maps the success value using the provided closure. Read more

fn map_err<E, F>(self, f: F) -> MapErr<Self, F> where
    F: FnMut(Self::Error) -> E, 
[src]

Wraps the current stream in a new stream which maps the error value using the provided closure. Read more

fn and_then<Fut, F>(self, f: F) -> AndThen<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: TryFuture<Error = Self::Error>, 
[src]

Chain on a computation for when a value is ready, passing the successful results to the provided closure f. Read more

fn or_else<Fut, F>(self, f: F) -> OrElse<Self, Fut, F> where
    F: FnMut(Self::Error) -> Fut,
    Fut: TryFuture<Ok = Self::Ok>, 
[src]

Chain on a computation for when an error happens, passing the erroneous result to the provided closure f. Read more

fn inspect_ok<F>(self, f: F) -> InspectOk<Self, F> where
    F: FnMut(&Self::Ok), 
[src]

Do something with the success value of this stream, afterwards passing it on. Read more

fn inspect_err<F>(self, f: F) -> InspectErr<Self, F> where
    F: FnMut(&Self::Error), 
[src]

Do something with the error value of this stream, afterwards passing it on. Read more

fn into_stream(self) -> IntoStream<Self>[src]

Wraps a TryStream into a type that implements Stream Read more

fn try_next(&mut self) -> TryNext<'_, Self> where
    Self: Unpin
[src]

Creates a future that attempts to resolve the next item in the stream. If an error is encountered before the next item, the error is returned instead. Read more

fn try_for_each<Fut, F>(self, f: F) -> TryForEach<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: TryFuture<Ok = (), Error = Self::Error>, 
[src]

Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more

fn try_skip_while<Fut, F>(self, f: F) -> TrySkipWhile<Self, Fut, F> where
    F: FnMut(&Self::Ok) -> Fut,
    Fut: TryFuture<Ok = bool, Error = Self::Error>, 
[src]

Skip elements on this stream while the provided asynchronous predicate resolves to true. Read more

fn try_take_while<Fut, F>(self, f: F) -> TryTakeWhile<Self, Fut, F> where
    F: FnMut(&Self::Ok) -> Fut,
    Fut: TryFuture<Ok = bool, Error = Self::Error>, 
[src]

Take elements on this stream while the provided asynchronous predicate resolves to true. Read more

fn try_for_each_concurrent<Fut, F>(
    self,
    limit: impl Into<Option<usize>>,
    f: F
) -> TryForEachConcurrent<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: Future<Output = Result<(), Self::Error>>, 
[src]

Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available, exiting as soon as an error occurs. Read more

fn try_collect<C>(self) -> TryCollect<Self, C> where
    C: Default + Extend<Self::Ok>, 
[src]

Attempt to transform a stream into a collection, returning a future representing the result of that computation. Read more

fn try_filter<Fut, F>(self, f: F) -> TryFilter<Self, Fut, F> where
    F: FnMut(&Self::Ok) -> Fut,
    Fut: Future<Output = bool>, 
[src]

Attempt to filter the values produced by this stream according to the provided asynchronous closure. Read more

fn try_filter_map<Fut, F, T>(self, f: F) -> TryFilterMap<Self, Fut, F> where
    F: FnMut(Self::Ok) -> Fut,
    Fut: TryFuture<Ok = Option<T>, Error = Self::Error>, 
[src]

Attempt to filter the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more

fn try_flatten(self) -> TryFlatten<Self> where
    Self::Ok: TryStream,
    <Self::Ok as TryStream>::Error: From<Self::Error>, 
[src]

Flattens a stream of streams into just one continuous stream. Read more

fn try_fold<T, Fut, F>(self, init: T, f: F) -> TryFold<Self, Fut, T, F> where
    F: FnMut(T, Self::Ok) -> Fut,
    Fut: TryFuture<Ok = T, Error = Self::Error>, 
[src]

Attempt to execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more

fn try_concat(self) -> TryConcat<Self> where
    Self::Ok: Extend<<Self::Ok as IntoIterator>::Item>,
    Self::Ok: IntoIterator,
    Self::Ok: Default
[src]

Attempt to concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more

fn try_buffer_unordered(self, n: usize) -> TryBufferUnordered<Self> where
    Self::Ok: TryFuture,
    <Self::Ok as TryFuture>::Error == Self::Error
[src]

Attempt to execute several futures from a stream concurrently (unordered). Read more

fn try_buffered(self, n: usize) -> TryBuffered<Self> where
    Self::Ok: TryFuture,
    <Self::Ok as TryFuture>::Error == Self::Error
[src]

Attempt to execute several futures from a stream concurrently. Read more

fn try_poll_next_unpin(
    &mut self,
    cx: &mut Context<'_>
) -> Poll<Option<Result<Self::Ok, Self::Error>>> where
    Self: Unpin
[src]

A convenience method for calling TryStream::try_poll_next on Unpin stream types. Read more

fn into_async_read(self) -> IntoAsyncRead<Self> where
    Self: TryStreamExt<Error = Error> + Unpin,
    Self::Ok: AsRef<[u8]>, 
[src]

Adapter that converts this stream into an AsyncRead. Read more

impl<V, T> VZip<V> for T where
    V: MultiLane<T>, 

pub fn vzip(self) -> V