Trait RequestPartsExt

pub trait RequestPartsExt: Sealed + Sized {
    // Required methods
    fn extract<E>(&mut self) -> BoxFuture<'_, Result<E, E::Rejection>>
       where E: FromRequestParts<()> + 'static;
    fn extract_with_state<'a, E, S>(
        &'a mut self,
        state: &'a S,
    ) -> BoxFuture<'a, Result<E, E::Rejection>>
       where E: FromRequestParts<S> + 'static,
             S: Send + Sync;
}

Extension trait that adds additional methods to Parts.

Required Methods

fn extract<E>(&mut self) -> BoxFuture<'_, Result<E, E::Rejection>>

where E: FromRequestParts<()> + 'static,

Apply an extractor to this Parts.

This is just a convenience for E::from_request_parts(parts, &()).

Example

use axum::{
    extract::{Query, Path, FromRequestParts},
    response::{Response, IntoResponse},
    http::request::Parts,
    RequestPartsExt,
    async_trait,
};
use std::collections::HashMap;

struct MyExtractor {
    path_params: HashMap<String, String>,
    query_params: HashMap<String, String>,
}

#[async_trait]
impl<S> FromRequestParts<S> for MyExtractor
where
    S: Send + Sync,
{
    type Rejection = Response;

    async fn from_request_parts(parts: &mut Parts, state: &S) -> Result<Self, Self::Rejection> {
        let path_params = parts
            .extract::<Path<HashMap<String, String>>>()
            .await
            .map(|Path(path_params)| path_params)
            .map_err(|err| err.into_response())?;

        let query_params = parts
            .extract::<Query<HashMap<String, String>>>()
            .await
            .map(|Query(params)| params)
            .map_err(|err| err.into_response())?;

        Ok(MyExtractor { path_params, query_params })
    }
}

fn extract_with_state<'a, E, S>( &'a mut self, state: &'a S, ) -> BoxFuture<'a, Result<E, E::Rejection>>

where E: FromRequestParts<S> + 'static, S: Send + Sync,

Apply an extractor that requires some state to this Parts.

This is just a convenience for E::from_request_parts(parts, state).

Example

use axum::{
    extract::{FromRef, FromRequestParts},
    response::{Response, IntoResponse},
    http::request::Parts,
    RequestPartsExt,
    async_trait,
};

struct MyExtractor {
    requires_state: RequiresState,
}

#[async_trait]
impl<S> FromRequestParts<S> for MyExtractor
where
    String: FromRef<S>,
    S: Send + Sync,
{
    type Rejection = std::convert::Infallible;

    async fn from_request_parts(parts: &mut Parts, state: &S) -> Result<Self, Self::Rejection> {
        let requires_state = parts
            .extract_with_state::<RequiresState, _>(state)
            .await?;

        Ok(MyExtractor { requires_state })
    }
}

struct RequiresState { /* ... */ }

// some extractor that requires a `String` in the state
#[async_trait]
impl<S> FromRequestParts<S> for RequiresState
where
    String: FromRef<S>,
    S: Send + Sync,
{
    // ...
}

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl RequestPartsExt for Parts

fn extract<E>(&mut self) -> BoxFuture<'_, Result<E, E::Rejection>>

where E: FromRequestParts<()> + 'static,

fn extract_with_state<'a, E, S>( &'a mut self, state: &'a S, ) -> BoxFuture<'a, Result<E, E::Rejection>>

where E: FromRequestParts<S> + 'static, S: Send + Sync,

Implementors