examples: Replaced custom Json extractor with WithRejection

This commit is contained in:
Altair-Bueno 2022-08-15 18:51:58 +02:00
parent 3770e7b057
commit d878eede18
2 changed files with 52 additions and 48 deletions

View file

@ -6,6 +6,7 @@ publish = false
[dependencies]
axum = { path = "../../axum" }
axum-extra = { path = "../../axum-extra" }
serde = { version = "1.0", features = ["derive"] }
serde_json = "1.0"
tokio = { version = "1.0", features = ["full"] }

View file

@ -5,15 +5,15 @@
//! ```
use axum::{
async_trait,
extract::{rejection::JsonRejection, FromRequest, RequestParts},
extract::rejection::JsonRejection,
http::StatusCode,
routing::post,
BoxError, Router,
response::IntoResponse,
routing::post, Json, Router,
};
use serde::{de::DeserializeOwned, Deserialize};
use serde_json::{json, Value};
use std::{borrow::Cow, net::SocketAddr};
use axum_extra::extract::WithRejection;
use serde::Deserialize;
use serde_json::json;
use std::net::SocketAddr;
use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};
#[tokio::main]
@ -38,7 +38,12 @@ async fn main() {
.unwrap();
}
async fn handler(Json(user): Json<User>) {
async fn handler(
// `WithRejection` will extract `Json<User>` from the request. If the
// extraction fails, a `MyRejection` will be created from `JsonResponse` and
// returned to the client
WithRejection(Json(user), _): WithRejection<Json<User>, MyRejection>
) {
dbg!(&user);
}
@ -49,46 +54,44 @@ struct User {
username: String,
}
// We define our own `Json` extractor that customizes the error from `axum::Json`
struct Json<T>(T);
// Define your own custom rejection
#[derive(Debug)]
struct MyRejection {
body: String,
status: StatusCode,
}
#[async_trait]
impl<B, T> FromRequest<B> for Json<T>
where
// these trait bounds are copied from `impl FromRequest for axum::Json`
T: DeserializeOwned,
B: axum::body::HttpBody + Send,
B::Data: Send,
B::Error: Into<BoxError>,
{
type Rejection = (StatusCode, axum::Json<Value>);
async fn from_request(req: &mut RequestParts<B>) -> Result<Self, Self::Rejection> {
match axum::Json::<T>::from_request(req).await {
Ok(value) => Ok(Self(value.0)),
Err(rejection) => {
// convert the error from `axum::Json` into whatever we want
let (status, body): (_, Cow<'_, str>) = match rejection {
JsonRejection::JsonDataError(err) => (
StatusCode::BAD_REQUEST,
format!("Invalid JSON request: {}", err).into(),
),
JsonRejection::MissingJsonContentType(err) => {
(StatusCode::BAD_REQUEST, err.to_string().into())
}
err => (
StatusCode::INTERNAL_SERVER_ERROR,
format!("Unknown internal error: {}", err).into(),
),
};
Err((
status,
// we use `axum::Json` here to generate a JSON response
// body but you can use whatever response you want
axum::Json(json!({ "error": body })),
))
}
}
// `IntoResponse` is required for your custom rejection type
impl IntoResponse for MyRejection {
fn into_response(self) -> axum::response::Response {
let Self { body, status } = self;
(
status,
// we use `axum::Json` here to generate a JSON response
// body but you can use whatever response you want
axum::Json(json!({ "error": body })),
)
.into_response()
}
}
// Implement `From` for any Rejection type you want
impl From<JsonRejection> for MyRejection {
fn from(rejection: JsonRejection) -> Self {
// convert the error from `axum::Json` into whatever we want
let (status, body) = match rejection {
JsonRejection::JsonDataError(err) => (
StatusCode::BAD_REQUEST,
format!("Invalid JSON request: {}", err),
),
JsonRejection::MissingJsonContentType(err) => {
(StatusCode::BAD_REQUEST, err.to_string())
}
err => (
StatusCode::INTERNAL_SERVER_ERROR,
format!("Unknown internal error: {}", err),
),
};
Self { body, status }
}
}