pub struct ReqData<T>(_) 
where
    T: 'static + Clone
;
Expand description

Request-local data extractor.

Request-local data is arbitrary data attached to an individual request, usually by middleware. It can be set via extensions_mut on HttpRequest or ServiceRequest.

Unlike app data, request data is dropped when the request has finished processing. This makes it useful as a kind of messaging system between middleware and request handlers. It uses the same types-as-keys storage system as app data.

Mutating Request Data

Note that since extractors must output owned data, only types that impl Clone can use this extractor. A clone is taken of the required request data and can, therefore, not be directly mutated in-place. To mutate request data, continue to use HttpRequest::extensions_mut or re-insert the cloned data back into the extensions map. A DerefMut impl is intentionally not provided to make this potential foot-gun more obvious.

Examples


#[derive(Debug, Clone, PartialEq)]
struct FlagFromMiddleware(String);

/// Use the `ReqData<T>` extractor to access request data in a handler.
async fn handler(
    req: HttpRequest,
    opt_flag: Option<web::ReqData<FlagFromMiddleware>>,
) -> impl Responder {
    // use an option extractor if middleware is not guaranteed to add this type of req data
    if let Some(flag) = opt_flag {
        assert_eq!(&flag.into_inner(), req.extensions().get::<FlagFromMiddleware>().unwrap());
    }

    HttpResponse::Ok()
}

Implementations

Consumes the ReqData, returning its wrapped data.

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

The resulting type after dereferencing.

Dereferences the value.

The associated error which can be returned.

Future that resolves to a Self. Read more

Create a Self from request parts asynchronously.

Create a Self from request head asynchronously. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Converts self into T using Into<T>. Read more

Extract a subset of the possible types in a coproduct (or get the remaining possibilities) Read more

Causes self to use its Binary implementation when Debug-formatted.

Causes self to use its Display implementation when Debug-formatted. Read more

Causes self to use its LowerExp implementation when Debug-formatted. Read more

Causes self to use its LowerHex implementation when Debug-formatted. Read more

Causes self to use its Octal implementation when Debug-formatted.

Causes self to use its Pointer implementation when Debug-formatted. Read more

Causes self to use its UpperExp implementation when Debug-formatted. Read more

Causes self to use its UpperHex implementation when Debug-formatted. Read more

Returns the argument unchanged.

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

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

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Performs the indexed conversion.

Pipes by value. This is generally the method you want to use. Read more

Borrows self and passes that borrow into the pipe function. Read more

Mutably borrows self and passes that borrow into the pipe function. Read more

Borrows self, then passes self.borrow() into the pipe function. Read more

Mutably borrows self, then passes self.borrow_mut() into the pipe function. Read more

Borrows self, then passes self.as_ref() into the pipe function.

Mutably borrows self, then passes self.as_mut() into the pipe function. Read more

Borrows self, then passes self.deref() into the pipe function.

Mutably borrows self, then passes self.deref_mut() into the pipe function. Read more

The alignment of pointer.

The type for initializers.

Initializes a with the given initializer. Read more

Dereferences the given pointer. Read more

Mutably dereferences the given pointer. Read more

Drops the object pointed to by the given pointer. Read more

Should always be Self

Consumes the current HList and returns an HList with the requested shape. Read more

Immutable access to a value. Read more

Mutable access to a value. Read more

Immutable access to the Borrow<B> of a value. Read more

Mutable access to the BorrowMut<B> of a value. Read more

Immutable access to the AsRef<R> view of a value. Read more

Mutable access to the AsMut<R> view of a value. Read more

Immutable access to the Deref::Target of a value. Read more

Mutable access to the Deref::Target of a value. Read more

Calls .tap() only in debug builds, and is erased in release builds.

Calls .tap_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_borrow() only in debug builds, and is erased in release builds. Read more

Calls .tap_borrow_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_ref() only in debug builds, and is erased in release builds. Read more

Calls .tap_ref_mut() only in debug builds, and is erased in release builds. Read more

Calls .tap_deref() only in debug builds, and is erased in release builds. Read more

Calls .tap_deref_mut() only in debug builds, and is erased in release builds. Read more

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

Uses borrowed data to replace owned data, usually by cloning. Read more

Attempts to convert self into T using TryInto<T>. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more