pub struct Channel { /* private fields */ }
Expand description
A default batteries included transport
channel.
This provides a fully featured http2 gRPC client based on [hyper::Client
]
and tower
services.
Multiplexing requests
Sending a request on a channel requires a &mut self
and thus can only send
one request in flight. This is intentional and is required to follow the Service
contract from the tower
library which this channel implementation is built on
top of.
tower
itself has a concept of poll_ready
which is the main mechanism to apply
back pressure. poll_ready
takes a &mut self
and when it returns Poll::Ready
we know the Service
is able to accept only one request before we must poll_ready
again. Due to this fact any async fn
that wants to poll for readiness and submit
the request must have a &mut self
reference.
To work around this and to ease the use of the channel, Channel
provides a
Clone
implementation that is cheap. This is because at the very top level
the channel is backed by a tower_buffer::Buffer
which runs the connection
in a background task and provides a mpsc
channel interface. Due to this
cloning the Channel
type is cheap and encouraged.
Implementations
sourceimpl Channel
impl Channel
sourcepub fn from_static(s: &'static str) -> Endpoint
pub fn from_static(s: &'static str) -> Endpoint
Create an Endpoint
from a static string.
Channel::from_static("https://example.com");
Create an Endpoint
from shared bytes.
Channel::from_shared("https://example.com");
sourcepub fn balance_list(list: impl Iterator<Item = Endpoint>) -> Channel
pub fn balance_list(list: impl Iterator<Item = Endpoint>) -> Channel
sourcepub fn balance_channel<K>(
capacity: usize
) -> (Channel, Sender<Change<K, Endpoint>>) where
K: 'static + Hash + Eq + Send + Clone,
pub fn balance_channel<K>(
capacity: usize
) -> (Channel, Sender<Change<K, Endpoint>>) where
K: 'static + Hash + Eq + Send + Clone,
Trait Implementations
sourceimpl Service<Request<UnsyncBoxBody<Bytes, Status>>> for Channel
impl Service<Request<UnsyncBoxBody<Bytes, Status>>> for Channel
type Future = ResponseFuture
type Future = ResponseFuture
The future response value.
sourcefn poll_ready(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(), <Channel as Service<Request<UnsyncBoxBody<Bytes, Status>>>>::Error>>
fn poll_ready(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(), <Channel as Service<Request<UnsyncBoxBody<Bytes, Status>>>>::Error>>
Returns Poll::Ready(Ok(()))
when the service is able to process requests. Read more
sourcefn call(
&mut self,
request: Request<UnsyncBoxBody<Bytes, Status>>
) -> <Channel as Service<Request<UnsyncBoxBody<Bytes, Status>>>>::Future
fn call(
&mut self,
request: Request<UnsyncBoxBody<Bytes, Status>>
) -> <Channel as Service<Request<UnsyncBoxBody<Bytes, Status>>>>::Future
Process the request and return the response asynchronously. Read more
Auto Trait Implementations
impl !RefUnwindSafe for Channel
impl Send for Channel
impl Sync for Channel
impl Unpin for Channel
impl !UnwindSafe for Channel
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T, ReqBody, ResBody> GrpcService<ReqBody> for T where
T: Service<Request<ReqBody>, Response = Response<ResBody>>,
ResBody: Body,
<T as Service<Request<ReqBody>>>::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
<ResBody as Body>::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
impl<T, ReqBody, ResBody> GrpcService<ReqBody> for T where
T: Service<Request<ReqBody>, Response = Response<ResBody>>,
ResBody: Body,
<T as Service<Request<ReqBody>>>::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
<ResBody as Body>::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
type ResponseBody = ResBody
type ResponseBody = ResBody
Responses body given by the service.
sourcefn poll_ready(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(), <T as GrpcService<ReqBody>>::Error>>
fn poll_ready(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(), <T as GrpcService<ReqBody>>::Error>>
Returns Ready
when the service is able to process requests. Read more
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn instrument(self, span: Span) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
T: Future, type Output = <T as Future>::Output;
sourcefn in_current_span(self) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn in_current_span(self) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
T: Future, type Output = <T as Future>::Output;
sourceimpl<T> IntoRequest<T> for T
impl<T> IntoRequest<T> for T
sourcefn into_request(self) -> Request<T>
fn into_request(self) -> Request<T>
Wrap the input message T
in a tonic::Request
impl<T, Request> ServiceExt<Request> for T where
T: Service<Request> + ?Sized,
impl<T, Request> ServiceExt<Request> for T where
T: Service<Request> + ?Sized,
fn ready(&mut self) -> Ready<'_, Self, Request>ⓘNotable traits for Ready<'a, T, Request>impl<'a, T, Request> Future for Ready<'a, T, Request> where
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
fn ready(&mut self) -> Ready<'_, Self, Request>ⓘNotable traits for Ready<'a, T, Request>impl<'a, T, Request> Future for Ready<'a, T, Request> where
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
Yields a mutable reference to the service when it is ready to accept a request.
fn ready_and(&mut self) -> Ready<'_, Self, Request>ⓘNotable traits for Ready<'a, T, Request>impl<'a, T, Request> Future for Ready<'a, T, Request> where
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
fn ready_and(&mut self) -> Ready<'_, Self, Request>ⓘNotable traits for Ready<'a, T, Request>impl<'a, T, Request> Future for Ready<'a, T, Request> where
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
T: Service<Request>, type Output = Result<&'a mut T, <T as Service<Request>>::Error>;
please use the ServiceExt::ready
method instead
Yields a mutable reference to the service when it is ready to accept a request.
fn ready_oneshot(self) -> ReadyOneshot<Self, Request>ⓘNotable traits for ReadyOneshot<T, Request>impl<T, Request> Future for ReadyOneshot<T, Request> where
T: Service<Request>, type Output = Result<T, <T as Service<Request>>::Error>;
fn ready_oneshot(self) -> ReadyOneshot<Self, Request>ⓘNotable traits for ReadyOneshot<T, Request>impl<T, Request> Future for ReadyOneshot<T, Request> where
T: Service<Request>, type Output = Result<T, <T as Service<Request>>::Error>;
T: Service<Request>, type Output = Result<T, <T as Service<Request>>::Error>;
Yields the service when it is ready to accept a request.
fn oneshot(self, req: Request) -> Oneshot<Self, Request>ⓘNotable traits for Oneshot<S, Req>impl<S, Req> Future for Oneshot<S, Req> where
S: Service<Req>, type Output = Result<<S as Service<Req>>::Response, <S as Service<Req>>::Error>;
fn oneshot(self, req: Request) -> Oneshot<Self, Request>ⓘNotable traits for Oneshot<S, Req>impl<S, Req> Future for Oneshot<S, Req> where
S: Service<Req>, type Output = Result<<S as Service<Req>>::Response, <S as Service<Req>>::Error>;
S: Service<Req>, type Output = Result<<S as Service<Req>>::Response, <S as Service<Req>>::Error>;
Consume this Service
, calling with the providing request once it is ready.
fn call_all<S>(self, reqs: S) -> CallAll<Self, S> where
S: Stream<Item = Request>,
Self::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
fn call_all<S>(self, reqs: S) -> CallAll<Self, S> where
S: Stream<Item = Request>,
Self::Error: Into<Box<dyn Error + Send + Sync + 'static, Global>>,
fn and_then<F>(self, f: F) -> AndThen<Self, F> where
F: Clone,
fn and_then<F>(self, f: F) -> AndThen<Self, F> where
F: Clone,
Executes a new future after this service’s future resolves. This does
not alter the behaviour of the poll_ready
method. Read more
fn map_response<F, Response>(self, f: F) -> MapResponse<Self, F> where
F: FnOnce(Self::Response) -> Response + Clone,
fn map_response<F, Response>(self, f: F) -> MapResponse<Self, F> where
F: FnOnce(Self::Response) -> Response + Clone,
Maps this service’s response value to a different value. This does not
alter the behaviour of the poll_ready
method. Read more
fn map_err<F, Error>(self, f: F) -> MapErr<Self, F> where
F: FnOnce(Self::Error) -> Error + Clone,
fn map_err<F, Error>(self, f: F) -> MapErr<Self, F> where
F: FnOnce(Self::Error) -> Error + Clone,
Maps this service’s error value to a different value. This does not
alter the behaviour of the poll_ready
method. Read more
fn map_result<F, Response, Error>(self, f: F) -> MapResult<Self, F> where
Error: From<Self::Error>,
F: FnOnce(Result<Self::Response, Self::Error>) -> Result<Response, Error> + Clone,
fn map_result<F, Response, Error>(self, f: F) -> MapResult<Self, F> where
Error: From<Self::Error>,
F: FnOnce(Result<Self::Response, Self::Error>) -> Result<Response, Error> + Clone,
Maps this service’s result type (Result<Self::Response, Self::Error>
)
to a different value, regardless of whether the future succeeds or
fails. Read more
fn map_request<F, NewRequest>(self, f: F) -> MapRequest<Self, F> where
F: FnMut(NewRequest) -> Request,
fn map_request<F, NewRequest>(self, f: F) -> MapRequest<Self, F> where
F: FnMut(NewRequest) -> Request,
Composes a function in front of the service. Read more
fn then<F, Response, Error, Fut>(self, f: F) -> Then<Self, F> where
Error: From<Self::Error>,
F: FnOnce(Result<Self::Response, Self::Error>) -> Fut + Clone,
Fut: Future<Output = Result<Response, Error>>,
fn then<F, Response, Error, Fut>(self, f: F) -> Then<Self, F> where
Error: From<Self::Error>,
F: FnOnce(Result<Self::Response, Self::Error>) -> Fut + Clone,
Fut: Future<Output = Result<Response, Error>>,
Composes an asynchronous function after this service. Read more
fn map_future<F, Fut, Response, Error>(self, f: F) -> MapFuture<Self, F> where
F: FnMut(Self::Future) -> Fut,
Error: From<Self::Error>,
Fut: Future<Output = Result<Response, Error>>,
fn map_future<F, Fut, Response, Error>(self, f: F) -> MapFuture<Self, F> where
F: FnMut(Self::Future) -> Fut,
Error: From<Self::Error>,
Fut: Future<Output = Result<Response, Error>>,
Composes a function that transforms futures produced by the service. Read more
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
fn vzip(self) -> V
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
where
S: Into<Dispatch>,
T: Future, type Output = <T as Future>::Output;
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
fn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
T: Future, type Output = <T as Future>::Output;
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more