Enum tower::util::Either

pub enum Either<A, B> {
    A(A),
    B(B),
}

Combine two different service types into a single type.

Both services must be of the same request, response, and error types. Either is useful for handling conditional branching in service middleware to different inner service types.

Variants

A(A)B(B)

Trait Implementations

impl<A, B> Clone for Either<A, B> where
    A: Clone,
    B: Clone, 

fn clone(&self) -> Either<A, B>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<A, B> Debug for Either<A, B> where
    A: Debug,
    B: Debug, 

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

Formats the value using the given formatter.

impl<A, B> Future for Either<A, B> where
    A: Future,
    B: Future<Item = <A as Future>::Item>,
    <A as Future>::Error: Into<Box<dyn Error + 'static + Send + Sync>>,
    <B as Future>::Error: Into<Box<dyn Error + 'static + Send + Sync>>, 

type Item = <A as Future>::Item

The type of value that this future will resolved with if it is successful.

type Error = Box<dyn Error + 'static + Send + Sync>

The type of error that this future will resolve with if it fails in a normal fashion.

fn poll(
    &mut self
) -> Result<Async<<Either<A, B> as Future>::Item>, <Either<A, B> as Future>::Error>

Query this future to see if its value has become available, registering interest if it is not.

fn wait(self) -> Result<Self::Item, Self::Error>

Block the current thread until this future is resolved.

fn map<F, U>(self, f: F) -> Map<Self, F> where
    F: FnOnce(Self::Item) -> U, 

Map this future's result to a different type, returning a new future of the resulting type.

fn map_err<F, E>(self, f: F) -> MapErr<Self, F> where
    F: FnOnce(Self::Error) -> E, 

Map this future's error to a different error, returning a new future.

fn from_err<E>(self) -> FromErr<Self, E> where
    E: From<Self::Error>, 

Map this future's error to any error implementing From for this future's Error, returning a new future.

fn then<F, B>(self, f: F) -> Then<Self, B, F> where
    B: IntoFuture,
    F: FnOnce(Result<Self::Item, Self::Error>) -> B, 

Chain on a computation for when a future finished, passing the result of the future to the provided closure f.

fn and_then<F, B>(self, f: F) -> AndThen<Self, B, F> where
    B: IntoFuture<Error = Self::Error>,
    F: FnOnce(Self::Item) -> B, 

Execute another future after this one has resolved successfully.

fn or_else<F, B>(self, f: F) -> OrElse<Self, B, F> where
    B: IntoFuture<Item = Self::Item>,
    F: FnOnce(Self::Error) -> B, 

Execute another future if this one resolves with an error.

fn select<B>(self, other: B) -> Select<Self, <B as IntoFuture>::Future> where
    B: IntoFuture<Item = Self::Item, Error = Self::Error>, 

Waits for either one of two futures to complete.

fn select2<B>(self, other: B) -> Select2<Self, <B as IntoFuture>::Future> where
    B: IntoFuture, 

Waits for either one of two differently-typed futures to complete.

fn join<B>(self, other: B) -> Join<Self, <B as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>, 

Joins the result of two futures, waiting for them both to complete.

fn join3<B, C>(
    self,
    b: B,
    c: C
) -> Join3<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn join4<B, C, D>(
    self,
    b: B,
    c: C,
    d: D
) -> Join4<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>,
    D: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn join5<B, C, D, E>(
    self,
    b: B,
    c: C,
    d: D,
    e: E
) -> Join5<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future, <E as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>,
    D: IntoFuture<Error = Self::Error>,
    E: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn into_stream(self) -> IntoStream<Self>

Convert this future into a single element stream.

fn flatten(self) -> Flatten<Self> where
    Self::Item: IntoFuture,
    <Self::Item as IntoFuture>::Error: From<Self::Error>, 

Flatten the execution of this future when the successful result of this future is itself another future.

fn flatten_stream(self) -> FlattenStream<Self> where
    Self::Item: Stream,
    <Self::Item as Stream>::Error == Self::Error, 

Flatten the execution of this future when the successful result of this future is a stream.

fn fuse(self) -> Fuse<Self>

Fuse a future such that poll will never again be called once it has completed.

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnOnce(&Self::Item), 

Do something with the item of a future, passing it on.

fn catch_unwind(self) -> CatchUnwind<Self> where
    Self: UnwindSafe, 

Catches unwinding panics while polling the future.

fn shared(self) -> Shared<Self>

Create a cloneable handle to this future where all handles will resolve to the same result.

impl<A, B, Request> Service<Request> for Either<A, B> where
    A: Service<Request>,
    B: Service<Request, Response = <A as Service<Request>>::Response>,
    <A as Service<Request>>::Error: Into<Box<dyn Error + 'static + Send + Sync>>,
    <B as Service<Request>>::Error: Into<Box<dyn Error + 'static + Send + Sync>>, 

type Response = <A as Service<Request>>::Response

Responses given by the service.

type Error = Box<dyn Error + 'static + Send + Sync>

Errors produced by the service.

type Future = Either<<A as Service<Request>>::Future, <B as Service<Request>>::Future>

The future response value.

fn poll_ready(
    &mut self
) -> Result<Async<()>, <Either<A, B> as Service<Request>>::Error>

Returns Ready when the service is able to process requests.

fn call(
    &mut self,
    request: Request
) -> <Either<A, B> as Service<Request>>::Future

Process the request and return the response asynchronously.