feat(server): add an option to disable adding the DATE header

src/proto/h1/conn.rs

@@ -59,6 +59,8 @@ where
                 h1_header_read_timeout_running: false,
                 preserve_header_case: false,
                 title_case_headers: false,
+                #[cfg(feature = "server")]
+                add_date: true,
                 h09_responses: false,
                 #[cfg(feature = "ffi")]
                 on_informational: None,
@@ -111,6 +113,11 @@ where
         self.state.preserve_header_case = true;
     }
 
+    #[cfg(feature = "server")]
+    pub(crate) fn disable_add_date(&mut self) {
+        self.state.add_date = false;
+    }
+
     #[cfg(feature = "client")]
     pub(crate) fn set_h09_responses(&mut self) {
         self.state.h09_responses = true;
@@ -558,6 +565,8 @@ where
                 keep_alive: self.state.wants_keep_alive(),
                 req_method: &mut self.state.method,
                 title_case_headers: self.state.title_case_headers,
+                #[cfg(feature = "server")]
+                add_date: self.state.add_date,
             },
             buf,
         ) {
@@ -827,6 +836,8 @@ struct State {
     h1_header_read_timeout_running: bool,
     preserve_header_case: bool,
     title_case_headers: bool,
+    #[cfg(feature = "server")]
+    add_date: bool,
     h09_responses: bool,
     /// If set, called with each 1xx informational response received for
     /// the current request. MUST be unset after a non-1xx response is

src/proto/h1/mod.rs

@@ -99,6 +99,8 @@ pub(crate) struct Encode<'a, T> {
     keep_alive: bool,
     req_method: &'a mut Option<Method>,
     title_case_headers: bool,
+    #[cfg(feature = "server")]
+    add_date: bool,
 }
 
 /// Extra flags that a request "wants", like expect-continue or upgrades.

src/proto/h1/role.rs

@@ -856,7 +856,7 @@ impl Server {
         }
 
         // cached date is much faster than formatting every request
-        if !wrote_date {
+        if !wrote_date && msg.add_date {
             dst.reserve(date::DATE_VALUE_LENGTH + 8);
             header_name_writer.write_header_name_with_colon(dst, "date: ", header::DATE);
             date::extend(dst);
@@ -2290,6 +2290,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: true,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2321,6 +2322,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: false,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2355,6 +2357,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: true,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2379,6 +2382,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut Some(Method::CONNECT),
                 title_case_headers: false,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2408,6 +2412,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: true,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2442,6 +2447,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: false,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2476,6 +2482,7 @@ mod tests {
                 keep_alive: true,
                 req_method: &mut None,
                 title_case_headers: true,
+                add_date: true,
             },
             &mut vec,
         )
@@ -2487,6 +2494,37 @@ mod tests {
         assert_eq!(&vec[..expected_response.len()], &expected_response[..]);
     }
 
+    #[test]
+    fn test_server_disable_add_date() {
+        use crate::proto::BodyLength;
+        use http::header::HeaderValue;
+
+        let mut head = MessageHead::default();
+        head.headers
+            .insert("content-length", HeaderValue::from_static("10"));
+        head.headers
+            .insert("content-type", HeaderValue::from_static("application/json"));
+
+        let mut vec = Vec::new();
+        Server::encode(
+            Encode {
+                head: &mut head,
+                body: Some(BodyLength::Known(10)),
+                keep_alive: true,
+                req_method: &mut None,
+                title_case_headers: false,
+                add_date: false,
+            },
+            &mut vec,
+        )
+        .unwrap();
+
+        let expected_response =
+            b"HTTP/1.1 200 OK\r\ncontent-length: 10\r\ncontent-type: application/json\r\n\r\n";
+
+        assert_eq!(vec, expected_response);
+    }
+
     #[test]
     fn parse_header_htabs() {
         let mut bytes = BytesMut::from("HTTP/1.1 200 OK\r\nserver: hello\tworld\r\n\r\n");
@@ -2677,6 +2715,7 @@ mod tests {
                     keep_alive: true,
                     req_method: &mut Some(Method::GET),
                     title_case_headers: false,
+                    add_date: true,
                 },
                 &mut vec,
             )
@@ -2705,6 +2744,7 @@ mod tests {
                     keep_alive: true,
                     req_method: &mut Some(Method::GET),
                     title_case_headers: false,
+                    add_date: true
                 },
                 &mut vec,
             )

src/server/conn.rs

@@ -102,6 +102,7 @@ pub struct Http<E = Exec> {
     h1_keep_alive: bool,
     h1_title_case_headers: bool,
     h1_preserve_header_case: bool,
+    add_date: bool,
     #[cfg(all(feature = "http1", feature = "runtime"))]
     h1_header_read_timeout: Option<Duration>,
     h1_writev: Option<bool>,
@@ -286,6 +287,7 @@ impl Http {
             h1_keep_alive: true,
             h1_title_case_headers: false,
             h1_preserve_header_case: false,
+            add_date: true,
             #[cfg(all(feature = "http1", feature = "runtime"))]
             h1_header_read_timeout: None,
             h1_writev: None,
@@ -375,6 +377,23 @@ impl<E> Http<E> {
         self
     }
 
+    /// Set whether to automatically add the `DATE` header to responses.
+    ///
+    /// If true, and a request does not include a `DATE` header, one will be
+    /// added automatically.
+    ///
+    /// It is a protocol violation not to include a `DATE` header unless the 
+    /// server does not have a clock capable of providing a reasonable 
+    /// approximation of the time.
+    ///
+    /// Currently, this setting is unimplemented for HTTP/2.
+    ///
+    /// Default is `true`. 
+    pub fn add_date(&mut self, enabled: bool) -> &mut Self {
+        self.add_date = enabled;
+        self
+    }
+
     /// Set a timeout for reading client request headers. If a client does not 
     /// transmit the entire header within this time, the connection is closed.
     ///
@@ -605,6 +624,7 @@ impl<E> Http<E> {
             h1_keep_alive: self.h1_keep_alive,
             h1_title_case_headers: self.h1_title_case_headers,
             h1_preserve_header_case: self.h1_preserve_header_case,
+            add_date: self.add_date,
             #[cfg(all(feature = "http1", feature = "runtime"))]
             h1_header_read_timeout: self.h1_header_read_timeout,
             h1_writev: self.h1_writev,
@@ -669,6 +689,9 @@ impl<E> Http<E> {
                 if self.h1_preserve_header_case {
                     conn.set_preserve_header_case();
                 }
+                if !self.add_date {
+                    conn.disable_add_date();
+                }
                 #[cfg(all(feature = "http1", feature = "runtime"))]
                 if let Some(header_read_timeout) = self.h1_header_read_timeout {
                     conn.set_http1_header_read_timeout(header_read_timeout);

src/server/server.rs

@@ -309,6 +309,22 @@ impl<I, E> Builder<I, E> {
         self
     }
 
+    /// Set whether to automatically add the `DATE` header to responses.
+    ///
+    /// If true, and a request does not include a `DATE` header, one will be
+    /// added automatically.
+    ///
+    /// It is a protocol violation not to include a `DATE` header unless the 
+    /// server does not have a clock capable of providing a reasonable 
+    /// approximation of the time.
+    ///
+    /// Currently, this setting is unimplemented for HTTP/2.
+    ///
+    /// Default is `true`. 
+    pub fn add_date(mut self, val: bool) -> Self {
+        self.protocol.add_date(val);
+        self
+    }
     /// Set a timeout for reading client request headers. If a client does not 
     /// transmit the entire header within this time, the connection is closed.
     ///