Struct Error 

pub struct Error { /* private fields */ }

General purpose Actix Web error.

An Actix Web error is used to carry errors from std::error through Actix in a convenient way. It can be created through converting errors with into().

Whenever it is created from an external object a response error is created for it that can be used to create an HTTP response from it this means that if you have access to an actix Error you can always get a ResponseError reference from it.

Implementations

impl Error

pub fn as_response_error(&self) -> &dyn ResponseError

Returns the reference to the underlying ResponseError.

pub fn as_error<T: ResponseError + 'static>(&self) -> Option<&T>

Similar to as_response_error but downcasts.

pub fn error_response(&self) -> HttpResponse

Shortcut for creating an HttpResponse.

pub fn add_response_mapper<F>(&mut self, mapper: F)

where F: Fn(HttpResponse) -> HttpResponse + 'static,

Adds a function that maps the HTTP response generated for this error.

Mappers are called in the order they are added each time error_response is called. A mapper may receive a response already modified by other mappers, so it should avoid relying on a particular position in the chain.

Prefer narrowly mutating the provided response. Preserve fields the mapper does not own, insert default headers only when absent, and merge list-valued headers without introducing duplicates. Mappers should also be deterministic and safe to call more than once.

Good

This mapper preserves the error response and adds a default only when it is absent:

use actix_web::{
    error,
    http::header::{self, HeaderValue},
};

let mut err = error::ErrorBadRequest("bad request");
err.add_response_mapper(|mut res| {
    if !res.headers().contains_key(header::CACHE_CONTROL) {
        res.headers_mut()
            .insert(header::CACHE_CONTROL, HeaderValue::from_static("no-store"));
    }

    res
});

assert_eq!(
    err.error_response().headers().get(header::CACHE_CONTROL),
    Some(&HeaderValue::from_static("no-store")),
);

Bad

Replacing the response discards the original status, body, headers, extensions, and any changes made by earlier mappers:

use actix_web::{error, HttpResponse};

let mut err = error::ErrorBadRequest("bad request");
err.add_response_mapper(|_| HttpResponse::InternalServerError().finish());

Trait Implementations

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<Box<dyn ResponseError>> for Error

fn from(value: Box<dyn ResponseError>) -> Self

Converts to this type from the input type.

impl<L, R> From<EitherExtractError<L, R>> for Error

where L: Into<Error>, R: Into<Error>,

fn from(err: EitherExtractError<L, R>) -> Error

Converts to this type from the input type.

impl From<Error> for Response<BoxBody>

fn from(err: Error) -> Response<BoxBody>

Converts to this type from the input type.

impl From<Error> for HttpResponse

fn from(err: Error) -> Self

Converts to this type from the input type.

impl<T: ResponseError + 'static> From<T> for Error

Error for any error that implements ResponseError

fn from(err: T) -> Error

Converts to this type from the input type.