expose app error by http service

src/client/connector.rs

@@ -285,12 +285,9 @@ impl Default for ClientConnector {
                 Arc::new(config)
             }
 
+            #[cfg_attr(rustfmt, rustfmt_skip)]
             #[cfg(not(any(
-                feature = "alpn",
-                feature = "ssl",
-                feature = "tls",
-                feature = "rust-tls",
-            )))]
+                feature = "alpn", feature = "ssl", feature = "tls", feature = "rust-tls")))]
             {
                 ()
             }

src/server/error.rs

@@ -24,8 +24,8 @@ pub enum AcceptorError<T> {
 /// A set of errors that can occur during dispatching http requests
 pub enum HttpDispatchError {
     /// Application error
-    #[fail(display = "Application specific error")]
-    AppError,
+    #[fail(display = "Application specific error: {}", _0)]
+    App(Error),
 
     /// An `io::Error` that occurred while trying to read or write to a network
     /// stream.
@@ -39,6 +39,16 @@ pub enum HttpDispatchError {
     /// HTTP2 error
     #[fail(display = "HTTP2 error: {}", _0)]
     Http2(http2::Error),
+
+    /// Unknown error
+    #[fail(display = "Unknown error")]
+    Unknown,
+}
+
+impl From<Error> for HttpDispatchError {
+    fn from(err: Error) -> Self {
+        HttpDispatchError::App(err)
+    }
 }
 
 impl From<io::Error> for HttpDispatchError {

src/server/h1.rs

@@ -49,6 +49,7 @@ pub(crate) struct Http1<T: IoStream, H: HttpHandler + 'static> {
     payload: Option<PayloadType>,
     buf: BytesMut,
     tasks: VecDeque<Entry<H>>,
+    error: Option<Error>,
     ka_enabled: bool,
     ka_expire: Instant,
     ka_timer: Option<Delay>,
@@ -113,6 +114,7 @@ where
             decoder: H1Decoder::new(),
             payload: None,
             tasks: VecDeque::new(),
+            error: None,
             addr,
             buf,
             settings,
@@ -321,7 +323,11 @@ where
                         return Ok(Async::NotReady);
                     }
                     self.flags.insert(Flags::ERROR);
-                    return Err(HttpDispatchError::AppError);
+                    return Err(self
+                        .error
+                        .take()
+                        .map(|e| e.into())
+                        .unwrap_or(HttpDispatchError::Unknown));
                 }
 
                 match self.tasks[idx].pipe.poll_io(&mut self.stream) {
@@ -357,12 +363,13 @@ where
                         io = true;
                     }
                     Err(err) => {
+                        error!("Unhandled error1: {}", err);
                         // it is not possible to recover from error
                         // during pipe handling, so just drop connection
                         self.read_disconnected();
                         self.write_disconnected();
                         self.tasks[idx].flags.insert(EntryFlags::ERROR);
-                        error!("Unhandled error1: {}", err);
+                        self.error = Some(err);
                         continue;
                     }
                 }
@@ -373,10 +380,11 @@ where
                         self.tasks[idx].flags.insert(EntryFlags::FINISHED)
                     }
                     Err(err) => {
+                        error!("Unhandled error: {}", err);
                         self.read_disconnected();
                         self.write_disconnected();
                         self.tasks[idx].flags.insert(EntryFlags::ERROR);
-                        error!("Unhandled error: {}", err);
+                        self.error = Some(err);
                         continue;
                     }
                 }

src/server/settings.rs

@@ -145,6 +145,7 @@ impl<H> Clone for WorkerSettings<H> {
 }
 
 impl<H> WorkerSettings<H> {
+    /// Create instance of `WorkerSettings`
     pub fn new(
         handler: H, keep_alive: KeepAlive, client_timeout: u64, settings: ServerSettings,
     ) -> WorkerSettings<H> {