Struct axum::Form

pub struct Form<T>(pub T);

URL encoded extractor and response.

As extractor

If used as an extractor, Form will deserialize form data from the request, specifically:

• If the request has a method of GET or HEAD, the form data will be read from the query string (same as with Query)
• If the request has a different method, the form will be read from the body of the request. It must have a content-type of application/x-www-form-urlencoded for this to work. If you want to parse multipart/form-data request bodies, use Multipart instead.

This matches how HTML forms are sent by browsers by default. In both cases, the inner type T must implement serde::Deserialize.

⚠️ Since parsing form data might require consuming the request body, the Form extractor must be last if there are multiple extractors in a handler. See “the order of extractors”

use axum::Form;
use serde::Deserialize;

#[derive(Deserialize)]
struct SignUp {
    username: String,
    password: String,
}

async fn accept_form(Form(sign_up): Form<SignUp>) {
    // ...
}

As response

Form can also be used to encode any type that implements serde::Serialize as application/x-www-form-urlencoded

use axum::Form;
use serde::Serialize;

#[derive(Serialize)]
struct Payload {
    value: String,
}

async fn handler() -> Form<Payload> {
    Form(Payload { value: "foo".to_owned() })
}

Tuple Fields

0: T

Trait Implementations

impl<T: Clone> Clone for Form<T>

fn clone(&self) -> Form<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Form<T>

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

Formats the value using the given formatter.

impl<T: Default> Default for Form<T>

fn default() -> Form<T>

Returns the “default value” for a type.

impl<T> Deref for Form<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T> DerefMut for Form<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<T, S> FromRequest<S> for Form<T>

where T: DeserializeOwned, S: Send + Sync,

type Rejection = FormRejection

If the extractor fails it’ll use this “rejection” type. A rejection is a kind of error that can be converted into a response.

fn from_request<'life0, 'async_trait>( req: Request, _state: &'life0 S, ) -> Pin<Box<dyn Future<Output = Result<Self, Self::Rejection>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Perform the extraction.

impl<T> IntoResponse for Form<T>

where T: Serialize,

fn into_response(self) -> Response

Create a response.

impl<T: Copy> Copy for Form<T>