pub struct Extension<T>(pub T);
Expand description
Extractor that gets a value from request extensions.
This is commonly used to share state across handlers.
Example
use axum::{
extract::Extension,
routing::get,
Router,
};
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.
Tuple Fields
0: T
Trait Implementations
sourceimpl<T, B> FromRequest<B> for Extension<T> where
T: Clone + Send + Sync + 'static,
B: Send,
impl<T, B> FromRequest<B> for Extension<T> where
T: Clone + Send + Sync + 'static,
B: Send,
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. Read more
sourcefn from_request<'life0, 'async_trait>(
req: &'life0 mut RequestParts<B>
) -> Pin<Box<dyn Future<Output = Result<Self, Self::Rejection>> + Send + 'async_trait>> where
'life0: 'async_trait,
Self: 'async_trait,
fn from_request<'life0, 'async_trait>(
req: &'life0 mut RequestParts<B>
) -> Pin<Box<dyn Future<Output = Result<Self, Self::Rejection>> + Send + 'async_trait>> where
'life0: 'async_trait,
Self: 'async_trait,
Perform the extraction.
impl<T: Copy> Copy for Extension<T>
Auto Trait Implementations
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
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcepub fn borrow_mut(&mut self) -> &mut T
pub fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
sourceimpl<T> Instrument for T
impl<T> Instrument for T
sourcefn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
sourcefn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
sourceimpl<T> PolicyExt for T where
T: ?Sized,
impl<T> PolicyExt for T where
T: ?Sized,
sourceimpl<T> ToOwned for T where
T: Clone,
impl<T> ToOwned for T where
T: Clone,
type Owned = T
type Owned = T
The resulting type after obtaining ownership.
sourcepub fn to_owned(&self) -> T
pub fn to_owned(&self) -> T
Creates owned data from borrowed data, usually by cloning. Read more
sourcepub fn clone_into(&self, target: &mut T)
pub fn clone_into(&self, target: &mut T)
toowned_clone_into
)Uses borrowed data to replace owned data, usually by cloning. Read more
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
impl<V, T> VZip<V> for T where
V: MultiLane<T>,
pub fn vzip(self) -> V
sourceimpl<T> WithSubscriber for T
impl<T> WithSubscriber for T
sourcefn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self> where
S: Into<Dispatch>,
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
sourcefn with_current_subscriber(self) -> WithDispatch<Self>
fn with_current_subscriber(self) -> WithDispatch<Self>
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more