use std::convert::TryFrom; use actix_http::error::InternalError; use actix_http::http::{ header::IntoHeaderValue, Error as HttpError, HeaderMap, HeaderName, StatusCode, }; use actix_http::{Error, Response, ResponseBuilder}; use bytes::{Bytes, BytesMut}; use crate::request::HttpRequest; /// Trait implemented by types that can be converted to a http response. /// /// Types that implement this trait can be used as the return type of a handler. pub trait Responder { /// Convert self to `Response`. fn respond_to(self, req: &HttpRequest) -> Response; /// Override a status code for a Responder. /// /// ```rust /// use actix_web::{HttpRequest, Responder, http::StatusCode}; /// /// fn index(req: HttpRequest) -> impl Responder { /// "Welcome!".with_status(StatusCode::OK) /// } /// # fn main() {} /// ``` fn with_status(self, status: StatusCode) -> CustomResponder where Self: Sized, { CustomResponder::new(self).with_status(status) } /// Add header to the Responder's response. /// /// ```rust /// use actix_web::{web, HttpRequest, Responder}; /// use serde::Serialize; /// /// #[derive(Serialize)] /// struct MyObj { /// name: String, /// } /// /// fn index(req: HttpRequest) -> impl Responder { /// web::Json( /// MyObj{name: "Name".to_string()} /// ) /// .with_header("x-version", "1.2.3") /// } /// # fn main() {} /// ``` fn with_header(self, key: K, value: V) -> CustomResponder where Self: Sized, HeaderName: TryFrom, >::Error: Into, V: IntoHeaderValue, { CustomResponder::new(self).with_header(key, value) } } impl Responder for Response { #[inline] fn respond_to(self, _: &HttpRequest) -> Response { self } } impl Responder for Option { fn respond_to(self, req: &HttpRequest) -> Response { match self { Some(t) => t.respond_to(req), None => Response::build(StatusCode::NOT_FOUND).finish(), } } } impl Responder for Result where T: Responder, E: Into, { fn respond_to(self, req: &HttpRequest) -> Response { match self { Ok(val) => val.respond_to(req), Err(e) => Response::from_error(e.into()), } } } impl Responder for ResponseBuilder { #[inline] fn respond_to(mut self, _: &HttpRequest) -> Response { self.finish() } } impl Responder for (T, StatusCode) { fn respond_to(self, req: &HttpRequest) -> Response { let mut res = self.0.respond_to(req); *res.status_mut() = self.1; res } } impl Responder for &'static str { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("text/plain; charset=utf-8") .body(self) } } impl Responder for &'static [u8] { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("application/octet-stream") .body(self) } } impl Responder for String { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("text/plain; charset=utf-8") .body(self) } } impl<'a> Responder for &'a String { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("text/plain; charset=utf-8") .body(self) } } impl Responder for Bytes { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("application/octet-stream") .body(self) } } impl Responder for BytesMut { fn respond_to(self, _: &HttpRequest) -> Response { Response::build(StatusCode::OK) .content_type("application/octet-stream") .body(self) } } /// Allows to override status code and headers for a responder. pub struct CustomResponder { responder: T, status: Option, headers: Option, error: Option, } impl CustomResponder { fn new(responder: T) -> Self { CustomResponder { responder, status: None, headers: None, error: None, } } /// Override a status code for the Responder's response. /// /// ```rust /// use actix_web::{HttpRequest, Responder, http::StatusCode}; /// /// fn index(req: HttpRequest) -> impl Responder { /// "Welcome!".with_status(StatusCode::OK) /// } /// # fn main() {} /// ``` pub fn with_status(mut self, status: StatusCode) -> Self { self.status = Some(status); self } /// Add header to the Responder's response. /// /// ```rust /// use actix_web::{web, HttpRequest, Responder}; /// use serde::Serialize; /// /// #[derive(Serialize)] /// struct MyObj { /// name: String, /// } /// /// fn index(req: HttpRequest) -> impl Responder { /// web::Json( /// MyObj{name: "Name".to_string()} /// ) /// .with_header("x-version", "1.2.3") /// } /// # fn main() {} /// ``` pub fn with_header(mut self, key: K, value: V) -> Self where HeaderName: TryFrom, >::Error: Into, V: IntoHeaderValue, { if self.headers.is_none() { self.headers = Some(HeaderMap::new()); } match HeaderName::try_from(key) { Ok(key) => match value.try_into() { Ok(value) => { self.headers.as_mut().unwrap().append(key, value); } Err(e) => self.error = Some(e.into()), }, Err(e) => self.error = Some(e.into()), }; self } } impl Responder for CustomResponder { fn respond_to(self, req: &HttpRequest) -> Response { let mut res = self.responder.respond_to(req); if let Some(status) = self.status { *res.status_mut() = status; } if let Some(ref headers) = self.headers { for (k, v) in headers { res.headers_mut().insert(k.clone(), v.clone()); } } res } } impl Responder for InternalError where T: std::fmt::Debug + std::fmt::Display + 'static, { fn respond_to(self, _: &HttpRequest) -> Response { Response::from_error(self.into()) } } #[cfg(test)] pub(crate) mod tests { use actix_service::Service; use bytes::{Bytes, BytesMut}; use super::*; use crate::dev::{Body, ResponseBody}; use crate::http::{header::CONTENT_TYPE, HeaderValue, StatusCode}; use crate::test::{init_service, TestRequest}; use crate::{error, web, App}; #[actix_rt::test] async fn test_option_responder() { let mut srv = init_service( App::new() .service( web::resource("/none").to(|| async { Option::<&'static str>::None }), ) .service(web::resource("/some").to(|| async { Some("some") })), ) .await; let req = TestRequest::with_uri("/none").to_request(); let resp = srv.call(req).await.unwrap(); assert_eq!(resp.status(), StatusCode::NOT_FOUND); let req = TestRequest::with_uri("/some").to_request(); let resp = srv.call(req).await.unwrap(); assert_eq!(resp.status(), StatusCode::OK); match resp.response().body() { ResponseBody::Body(Body::Bytes(ref b)) => { let bytes = b.clone(); assert_eq!(bytes, Bytes::from_static(b"some")); } _ => panic!(), } } pub(crate) trait BodyTest { fn bin_ref(&self) -> &[u8]; fn body(&self) -> &Body; } impl BodyTest for ResponseBody { fn bin_ref(&self) -> &[u8] { match self { ResponseBody::Body(ref b) => match b { Body::Bytes(ref bin) => &bin, _ => panic!(), }, ResponseBody::Other(ref b) => match b { Body::Bytes(ref bin) => &bin, _ => panic!(), }, } } fn body(&self) -> &Body { match self { ResponseBody::Body(ref b) => b, ResponseBody::Other(ref b) => b, } } } #[actix_rt::test] async fn test_responder() { let req = TestRequest::default().to_http_request(); let resp = "test".respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("text/plain; charset=utf-8") ); let resp = b"test".respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("application/octet-stream") ); let resp = "test".to_string().respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("text/plain; charset=utf-8") ); let resp = (&"test".to_string()).respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("text/plain; charset=utf-8") ); let resp = Bytes::from_static(b"test").respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("application/octet-stream") ); let resp = BytesMut::from(b"test".as_ref()).respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("application/octet-stream") ); // InternalError let resp = error::InternalError::new("err", StatusCode::BAD_REQUEST).respond_to(&req); assert_eq!(resp.status(), StatusCode::BAD_REQUEST); } #[actix_rt::test] async fn test_result_responder() { let req = TestRequest::default().to_http_request(); // Result let resp = Ok::<_, Error>("test".to_string()).respond_to(&req); assert_eq!(resp.status(), StatusCode::OK); assert_eq!(resp.body().bin_ref(), b"test"); assert_eq!( resp.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("text/plain; charset=utf-8") ); let res = Err::(error::InternalError::new("err", StatusCode::BAD_REQUEST)) .respond_to(&req); assert_eq!(res.status(), StatusCode::BAD_REQUEST); } #[actix_rt::test] async fn test_custom_responder() { let req = TestRequest::default().to_http_request(); let res = "test" .to_string() .with_status(StatusCode::BAD_REQUEST) .respond_to(&req); assert_eq!(res.status(), StatusCode::BAD_REQUEST); assert_eq!(res.body().bin_ref(), b"test"); let res = "test" .to_string() .with_header("content-type", "json") .respond_to(&req); assert_eq!(res.status(), StatusCode::OK); assert_eq!(res.body().bin_ref(), b"test"); assert_eq!( res.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("json") ); } #[actix_rt::test] async fn test_tuple_responder_with_status_code() { let req = TestRequest::default().to_http_request(); let res = ("test".to_string(), StatusCode::BAD_REQUEST).respond_to(&req); assert_eq!(res.status(), StatusCode::BAD_REQUEST); assert_eq!(res.body().bin_ref(), b"test"); let req = TestRequest::default().to_http_request(); let res = ("test".to_string(), StatusCode::OK) .with_header("content-type", "json") .respond_to(&req); assert_eq!(res.status(), StatusCode::OK); assert_eq!(res.body().bin_ref(), b"test"); assert_eq!( res.headers().get(CONTENT_TYPE).unwrap(), HeaderValue::from_static("json") ); } }