Struct actix_web::web::Json

pub struct Json<T>(pub T);

Json helper

Json can be used for two different purpose. First is for json response generation and second is for extracting typed information from request's payload.

To extract typed information from request's body, the type T must implement the Deserialize trait from serde.

JsonConfig allows to configure extraction process.

Example

#[macro_use] extern crate serde_derive;
use actix_web::{web, App};

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

/// deserialize `Info` from request's body
fn index(info: web::Json<Info>) -> String {
    format!("Welcome {}!", info.username)
}

fn main() {
    let app = App::new().service(
       web::resource("/index.html").route(
           web::post().to(index))
    );
}

The Json type allows you to respond with well-formed JSON data: simply return a value of type Json where T is the type of a structure to serialize into JSON. The type T must implement the Serialize trait from serde.

#[derive(Serialize)]
struct MyObj {
    name: String,
}

fn index(req: HttpRequest) -> Result<web::Json<MyObj>> {
    Ok(web::Json(MyObj {
        name: req.match_info().get("name").unwrap().to_string(),
    }))
}

Methods

impl<T> Json<T>

pub fn into_inner(self) -> T

Deconstruct to an inner value

Trait Implementations

impl<T> FromRequest for Json<T> where
    T: DeserializeOwned + 'static, 

Json extractor. Allow to extract typed information from request's payload.

To extract typed information from request's body, the type T must implement the Deserialize trait from serde.

JsonConfig allows to configure extraction process.

Example

#[macro_use] extern crate serde_derive;
use actix_web::{web, App};

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

/// deserialize `Info` from request's body
fn index(info: web::Json<Info>) -> String {
    format!("Welcome {}!", info.username)
}

fn main() {
    let app = App::new().service(
        web::resource("/index.html").route(
           web::post().to(index))
    );
}

type Config = JsonConfig

Configuration for this extractor

type Error = Error

The associated error which can be returned.

type Future = Box<dyn Future<Item = Self, Error = Error>>

Future that resolves to a Self

fn from_request(req: &HttpRequest, payload: &mut Payload) -> Self::Future

Convert request to a Self

fn extract(req: &HttpRequest) -> Self::Future

Convert request to a Self

fn configure<F>(f: F) -> Self::Config where
    F: FnOnce(Self::Config) -> Self::Config, 

Create and configure config instance.

impl<T: Serialize> Responder for Json<T>

type Error = Error

The associated error which can be returned.

type Future = Result<Response, Error>

The future response value.

fn respond_to(self, _: &HttpRequest) -> Self::Future

Convert itself to AsyncResult or Error.

impl<T> Debug for Json<T> where
    T: Debug, 

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

Formats the value using the given formatter.

impl<T> DerefMut for Json<T>

fn deref_mut(&mut self) -> &mut T

Mutably dereferences the value.

impl<T> Deref for Json<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &T

Dereferences the value.

impl<T> Display for Json<T> where
    T: Display, 

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

Formats the value using the given formatter.