pub struct Extension<T>(pub T);
Expand description
Extractor and response for extensions.
§As extractor
This is commonly used to share state across handlers.
use axum::{
Router,
Extension,
routing::get,
};
use std::sync::Arc;
// Some shared state used throughout our application
struct State {
// ...
}
async fn handler(state: Extension<Arc<State>>) {
// ...
}
let state = Arc::new(State { /* ... */ });
let app = Router::new().route("/", get(handler))
// Add middleware that inserts the state into all incoming request's
// extensions.
.layer(Extension(state));
If the extension is missing it will reject the request with a 500 Internal Server Error
response.
§As response
Response extensions can be used to share state with middleware.
use axum::{
Extension,
response::IntoResponse,
};
async fn handler() -> (Extension<Foo>, &'static str) {
(
Extension(Foo("foo")),
"Hello, World!"
)
}
#[derive(Clone)]
struct Foo(&'static str);
Tuple Fields§
§0: T
Trait Implementations§
source§impl<T, S> FromRequestParts<S> for Extension<T>
impl<T, S> FromRequestParts<S> for Extension<T>
source§type Rejection = ExtensionRejection
type Rejection = ExtensionRejection
If the extractor fails it’ll use this “rejection” type. A rejection is
a kind of error that can be converted into a response.
source§impl<T> IntoResponse for Extension<T>
impl<T> IntoResponse for Extension<T>
source§fn into_response(self) -> Response
fn into_response(self) -> Response
Create a response.
source§impl<T> IntoResponseParts for Extension<T>
impl<T> IntoResponseParts for Extension<T>
source§type Error = Infallible
type Error = Infallible
The type returned in the event of an error. Read more
source§fn into_response_parts(
self,
res: ResponseParts,
) -> Result<ResponseParts, Self::Error>
fn into_response_parts( self, res: ResponseParts, ) -> Result<ResponseParts, Self::Error>
Set parts of the response
impl<T: Copy> Copy for Extension<T>
Auto Trait Implementations§
impl<T> Freeze for Extension<T>where
T: Freeze,
impl<T> RefUnwindSafe for Extension<T>where
T: RefUnwindSafe,
impl<T> Send for Extension<T>where
T: Send,
impl<T> Sync for Extension<T>where
T: Sync,
impl<T> Unpin for Extension<T>where
T: Unpin,
impl<T> UnwindSafe for Extension<T>where
T: UnwindSafe,
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
🔬This is a nightly-only experimental API. (
clone_to_uninit
)source§impl<S, T> FromRequest<S, ViaParts> for T
impl<S, T> FromRequest<S, ViaParts> for T
source§type Rejection = <T as FromRequestParts<S>>::Rejection
type Rejection = <T as FromRequestParts<S>>::Rejection
If the extractor fails it’ll use this “rejection” type. A rejection is
a kind of error that can be converted into a response.
source§impl<H, T> HandlerWithoutStateExt<T> for H
impl<H, T> HandlerWithoutStateExt<T> for H
source§fn into_service(self) -> HandlerService<H, T, ()>
fn into_service(self) -> HandlerService<H, T, ()>
Convert the handler into a
Service
and no state.source§fn into_make_service(self) -> IntoMakeService<HandlerService<H, T, ()>>
fn into_make_service(self) -> IntoMakeService<HandlerService<H, T, ()>>
Convert the handler into a
MakeService
and no state. Read moresource§fn into_make_service_with_connect_info<C>(
self,
) -> IntoMakeServiceWithConnectInfo<HandlerService<H, T, ()>, C>
fn into_make_service_with_connect_info<C>( self, ) -> IntoMakeServiceWithConnectInfo<HandlerService<H, T, ()>, C>
Convert the handler into a
MakeService
which stores information
about the incoming connection and has no state. Read more