feat(lib): missing Timer will warn or panic

If a default timeout is set, and no Timer, a warning will be emitted.

If a timeout is configured by the user, and no Timer is set, it will
panic.

Closes #3393

src/common/time.rs

@@ -1,4 +1,7 @@
-#[cfg(all(any(feature = "client", feature = "server"), feature = "http2"))]
+#[cfg(any(
+    all(any(feature = "client", feature = "server"), feature = "http2"),
+    all(feature = "server", feature = "http1"),
+))]
 use std::time::Duration;
 use std::{fmt, sync::Arc};
 use std::{pin::Pin, time::Instant};
@@ -13,46 +16,19 @@ pub(crate) enum Time {
     Empty,
 }
 
+#[cfg(all(feature = "server", feature = "http1"))]
+#[derive(Clone, Copy, Debug)]
+pub(crate) enum Dur {
+    Default(Option<Duration>),
+    Configured(Option<Duration>),
+}
+
 impl fmt::Debug for Time {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("Time").finish()
     }
 }
 
-/*
-pub(crate) fn timeout<F>(tim: Tim, future: F, duration: Duration) -> HyperTimeout<F> {
-    HyperTimeout { sleep: tim.sleep(duration), future: future }
-}
-
-pin_project_lite::pin_project! {
-    pub(crate) struct HyperTimeout<F> {
-        sleep: Box<dyn Sleep>,
-        #[pin]
-        future: F
-    }
-}
-
-pub(crate) struct Timeout;
-
-impl<F> Future for HyperTimeout<F> where F: Future {
-
-    type Output = Result<F::Output, Timeout>;
-
-    fn poll(self: Pin<&mut Self>, ctx: &mut Context<'_>) -> Poll<Self::Output>{
-        let mut this = self.project();
-        if let Poll::Ready(v) = this.future.poll(ctx) {
-            return Poll::Ready(Ok(v));
-        }
-
-        if let Poll::Ready(_) = Pin::new(&mut this.sleep).poll(ctx) {
-            return Poll::Ready(Err(Timeout));
-        }
-
-        return Poll::Pending;
-    }
-}
-*/
-
 impl Time {
     #[cfg(all(any(feature = "client", feature = "server"), feature = "http2"))]
     pub(crate) fn sleep(&self, duration: Duration) -> Pin<Box<dyn Sleep>> {
@@ -82,4 +58,22 @@ impl Time {
             Time::Timer(ref t) => t.reset(sleep, new_deadline),
         }
     }
+
+    #[cfg(all(feature = "server", feature = "http1"))]
+    pub(crate) fn check(&self, dur: Dur, name: &'static str) -> Option<Duration> {
+        match dur {
+            Dur::Default(Some(dur)) => match self {
+                Time::Empty => {
+                    warn!("timeout `{}` has default, but no timer set", name,);
+                    None
+                }
+                Time::Timer(..) => Some(dur),
+            },
+            Dur::Configured(Some(dur)) => match self {
+                Time::Empty => panic!("timeout `{}` set, but no timer set", name,),
+                Time::Timer(..) => Some(dur),
+            },
+            Dur::Default(None) | Dur::Configured(None) => None,
+        }
+    }
 }

src/server/conn/http1.rs

@@ -15,7 +15,10 @@ use bytes::Bytes;
 use crate::body::{Body, Incoming as IncomingBody};
 use crate::proto;
 use crate::service::HttpService;
-use crate::{common::time::Time, rt::Timer};
+use crate::{
+    common::time::{Dur, Time},
+    rt::Timer,
+};
 
 type Http1Dispatcher<T, B, S> = proto::h1::Dispatcher<
     proto::h1::dispatch::Server<S, IncomingBody>,
@@ -70,7 +73,7 @@ pub struct Builder {
     h1_keep_alive: bool,
     h1_title_case_headers: bool,
     h1_preserve_header_case: bool,
-    h1_header_read_timeout: Option<Duration>,
+    h1_header_read_timeout: Dur,
     h1_writev: Option<bool>,
     max_buf_size: Option<usize>,
     pipeline_flush: bool,
@@ -237,7 +240,7 @@ impl Builder {
             h1_keep_alive: true,
             h1_title_case_headers: false,
             h1_preserve_header_case: false,
-            h1_header_read_timeout: None,
+            h1_header_read_timeout: Dur::Default(None),
             h1_writev: None,
             max_buf_size: None,
             pipeline_flush: false,
@@ -293,8 +296,8 @@ impl Builder {
     /// transmit the entire header within this time, the connection is closed.
     ///
     /// Default is None.
-    pub fn header_read_timeout(&mut self, read_timeout: Duration) -> &mut Self {
-        self.h1_header_read_timeout = Some(read_timeout);
+    pub fn header_read_timeout(&mut self, read_timeout: impl Into<Option<Duration>>) -> &mut Self {
+        self.h1_header_read_timeout = Dur::Configured(read_timeout.into());
         self
     }
 
@@ -355,6 +358,11 @@ impl Builder {
     /// This returns a Future that must be polled in order for HTTP to be
     /// driven on the connection.
     ///
+    /// # Panics
+    ///
+    /// If a timeout option has been configured, but a `timer` has not been
+    /// provided, calling `serve_connection` will panic.
+    ///
     /// # Example
     ///
     /// ```
@@ -400,9 +408,12 @@ impl Builder {
         if self.h1_preserve_header_case {
             conn.set_preserve_header_case();
         }
-        if let Some(header_read_timeout) = self.h1_header_read_timeout {
-            conn.set_http1_header_read_timeout(header_read_timeout);
-        }
+        if let Some(dur) = self
+            .timer
+            .check(self.h1_header_read_timeout, "header_read_timeout")
+        {
+            conn.set_http1_header_read_timeout(dur);
+        };
         if let Some(writev) = self.h1_writev {
             if writev {
                 conn.set_write_strategy_queue();