move blocking error to web (#2660)

actix-web/CHANGES.md

@@ -1,6 +1,7 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+### Changed
 - Rename `test::{simple_service => status_service}`. [#2659]
 
 [#2659]: https://github.com/actix/actix-web/pull/2659

actix-web/src/error/error.rs

@@ -47,7 +47,6 @@ impl fmt::Debug for Error {
 
 impl StdError for Error {
     fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-        // TODO: populate if replacement for Box<dyn Error> is found
         None
     }
 }

actix-web/src/error/mod.rs

@@ -6,7 +6,7 @@
 //
 // See <https://github.com/rust-lang/rust/issues/83375>
 pub use actix_http::error::{
-    BlockingError, ContentTypeError, DispatchError, HttpError, ParseError, PayloadError,
+    ContentTypeError, DispatchError, HttpError, ParseError, PayloadError,
 };
 
 use derive_more::{Display, Error, From};
@@ -33,6 +33,14 @@ pub(crate) use macros::{downcast_dyn, downcast_get_type_id};
 /// This type alias is generally used to avoid writing out `actix_http::Error` directly.
 pub type Result<T, E = Error> = std::result::Result<T, E>;
 
+/// An error representing a problem running a blocking task on a thread pool.
+#[derive(Debug, Display, Error)]
+#[display(fmt = "Blocking thread pool is shut down unexpectedly")]
+#[non_exhaustive]
+pub struct BlockingError;
+
+impl ResponseError for crate::error::BlockingError {}
+
 /// Errors which can occur when attempting to generate resource uri.
 #[derive(Debug, PartialEq, Display, Error, From)]
 #[non_exhaustive]

actix-web/src/error/response_error.rs

@@ -6,20 +6,22 @@ use std::{
     io::{self, Write as _},
 };
 
-use actix_http::{
-    body::BoxBody,
-    header::{self, TryIntoHeaderValue},
-    Response, StatusCode,
-};
+use actix_http::Response;
 use bytes::BytesMut;
 
 use crate::{
+    body::BoxBody,
     error::{downcast_dyn, downcast_get_type_id},
-    helpers, HttpResponse,
+    helpers,
+    http::{
+        header::{self, TryIntoHeaderValue},
+        StatusCode,
+    },
+    HttpResponse,
 };
 
 /// Errors that can generate responses.
-// TODO: add std::error::Error bound when replacement for Box<dyn Error> is found
+// TODO: flesh out documentation
 pub trait ResponseError: fmt::Debug + fmt::Display {
     /// Returns appropriate status code for error.
     ///
@@ -73,7 +75,6 @@ impl ResponseError for std::str::Utf8Error {
 
 impl ResponseError for std::io::Error {
     fn status_code(&self) -> StatusCode {
-        // TODO: decide if these errors should consider not found or permission errors
         match self.kind() {
             io::ErrorKind::NotFound => StatusCode::NOT_FOUND,
             io::ErrorKind::PermissionDenied => StatusCode::FORBIDDEN,
@@ -86,7 +87,6 @@ impl ResponseError for actix_http::error::HttpError {}
 
 impl ResponseError for actix_http::Error {
     fn status_code(&self) -> StatusCode {
-        // TODO: map error kinds to status code better
         StatusCode::INTERNAL_SERVER_ERROR
     }
 
@@ -107,8 +107,6 @@ impl ResponseError for actix_http::error::ParseError {
     }
 }
 
-impl ResponseError for actix_http::error::BlockingError {}
-
 impl ResponseError for actix_http::error::PayloadError {
     fn status_code(&self) -> StatusCode {
         match *self {

actix-web/src/http/mod.rs

@@ -2,5 +2,4 @@
 
 pub mod header;
 
-// TODO: figure out how best to expose http::Error vs actix_http::Error
 pub use actix_http::{uri, ConnectionType, Error, KeepAlive, Method, StatusCode, Uri, Version};