Fix response part of rwf2#1067 by importing typed headers from 'heade…

…rs' crate

core/http/Cargo.toml

@@ -36,6 +36,7 @@ memchr = "2"
 stable-pattern = "0.1"
 cookie = { version = "0.18", features = ["percent-encode"] }
 state = "0.6"
+headers = "0.4.0"
 
 [dependencies.serde]
 version = "1.0"

core/http/src/header/header.rs

@@ -1,6 +1,8 @@
+use core::str;
 use std::borrow::{Borrow, Cow};
 use std::fmt;
 
+use headers::{Header as HHeader, HeaderValue};
 use indexmap::IndexMap;
 
 use crate::uncased::{Uncased, UncasedStr};
@@ -798,10 +800,153 @@ impl From<&cookie::Cookie<'_>> for Header<'static> {
     }
 }
 
+/// A destination for `HeaderValue`s that can be used to accumulate
+/// a single header value using from hyperium headers' decode protocol.
+#[derive(Default)]
+struct HeaderValueDestination {
+    value: Option<HeaderValue>,
+    count: usize,
+}
+
+impl <'r>HeaderValueDestination {
+    fn into_value(self) -> HeaderValue {
+        if let Some(value) = self.value {
+            // TODO: if value.count > 1, then log that multiple header values are
+            // generated by the typed header, but that the dropped.
+            value
+        } else {
+            // Perhaps log that the typed header didn't create any values.
+            // This won't happen in the current implementation (headers 0.4.0).
+            HeaderValue::from_static("")
+        }
+    }
+
+    fn into_header_string(self) -> Cow<'static, str> {
+        let value = self.into_value();
+        // TODO: Optimize if we know this is a static reference.
+        value.to_str().unwrap_or("").to_string().into()
+    }
+}
+
+impl Extend<HeaderValue> for HeaderValueDestination {
+    fn extend<T: IntoIterator<Item = HeaderValue>>(&mut self, iter: T) {
+        for value in iter {
+            self.count += 1;
+            if self.value.is_none() {
+                self.value = Some(value)
+            }
+        }
+    }
+}
+
+macro_rules! import_typed_headers {
+($($name:ident),*) => ($(
+    pub use headers::$name;
+
+    impl ::std::convert::From<self::$name> for Header<'static> {
+        fn from(header: self::$name) -> Self {
+            let mut destination = HeaderValueDestination::default();
+            header.encode(&mut destination);
+            let name = self::$name::name();
+            Header::new(name.as_str(), destination.into_header_string())
+        }
+    }
+)*)
+}
+
+macro_rules! import_generic_typed_headers {
+($($name:ident<$bound:ident>),*) => ($(
+    pub use headers::$name;
+
+    impl <T1: 'static + $bound>::std::convert::From<self::$name<T1>>
+        for Header<'static> {
+        fn from(header: self::$name<T1>) -> Self {
+            let mut destination = HeaderValueDestination::default();
+            header.encode(&mut destination);
+            let name = self::$name::<T1>::name();
+            Header::new(name.as_str(), destination.into_header_string())
+        }
+    }
+)*)
+}
+
+// The following headers from 'headers' 0.4 are not imported, since they are
+// provided by other Rocket features.
+
+// * ContentType, // Content-Type header, defined in RFC7231
+// * Cookie, // Cookie header, defined in RFC6265
+// * Host, // The Host header.
+// * Location, // Location header, defined in RFC7231
+// * SetCookie, // Set-Cookie header, defined RFC6265
+
+import_typed_headers! {
+  AcceptRanges, // Accept-Ranges header, defined in RFC7233
+  AccessControlAllowCredentials, // Access-Control-Allow-Credentials header, part of CORS
+  AccessControlAllowHeaders, // Access-Control-Allow-Headers header, part of CORS
+  AccessControlAllowMethods, // Access-Control-Allow-Methods header, part of CORS
+  AccessControlAllowOrigin, // The Access-Control-Allow-Origin response header, part of CORS
+  AccessControlExposeHeaders, // Access-Control-Expose-Headers header, part of CORS
+  AccessControlMaxAge, // Access-Control-Max-Age header, part of CORS
+  AccessControlRequestHeaders, // Access-Control-Request-Headers header, part of CORS
+  AccessControlRequestMethod, // Access-Control-Request-Method header, part of CORS
+  Age, // Age header, defined in RFC7234
+  Allow, // Allow header, defined in RFC7231
+  CacheControl, // Cache-Control header, defined in RFC7234 with extensions in RFC8246
+  Connection, // Connection header, defined in RFC7230
+  ContentDisposition, // A Content-Disposition header, (re)defined in RFC6266.
+  ContentEncoding, // Content-Encoding header, defined in RFC7231
+  ContentLength, // Content-Length header, defined in RFC7230
+  ContentLocation, // Content-Location header, defined in RFC7231
+  ContentRange, // Content-Range, described in RFC7233
+  Date, // Date header, defined in RFC7231
+  ETag, // ETag header, defined in RFC7232
+  Expect, // The Expect header.
+  Expires, // Expires header, defined in RFC7234
+  IfMatch, // If-Match header, defined in RFC7232
+  IfModifiedSince, // If-Modified-Since header, defined in RFC7232
+  IfNoneMatch, // If-None-Match header, defined in RFC7232
+  IfRange, // If-Range header, defined in RFC7233
+  IfUnmodifiedSince, // If-Unmodified-Since header, defined in RFC7232
+  LastModified, // Last-Modified header, defined in RFC7232
+  Origin, // The Origin header.
+  Pragma, // The Pragma header defined by HTTP/1.0.
+  Range, // Range header, defined in RFC7233
+  Referer, // Referer header, defined in RFC7231
+  ReferrerPolicy, // Referrer-Policy header, part of Referrer Policy
+  RetryAfter, // The Retry-After header.
+  SecWebsocketAccept, // The Sec-Websocket-Accept header.
+  SecWebsocketKey, // The Sec-Websocket-Key header.
+  SecWebsocketVersion, // The Sec-Websocket-Version header.
+  Server, // Server header, defined in RFC7231
+  StrictTransportSecurity, // StrictTransportSecurity header, defined in RFC6797
+  Te, // TE header, defined in RFC7230
+  TransferEncoding, // Transfer-Encoding header, defined in RFC7230
+  Upgrade, // Upgrade header, defined in RFC7230
+  UserAgent, // User-Agent header, defined in RFC7231
+  Vary // Vary header, defined in RFC7231
+}
+
+import_generic_typed_headers! {
+    Authorization<Credentials>, // Authorization header, defined in RFC7235
+    ProxyAuthorization<Credentials> // Proxy-Authorization header, defined in RFC7235
+}
+
+pub use headers::authorization::Credentials;
+
 #[cfg(test)]
 mod tests {
+    use std::time::SystemTime;
+
     use super::HeaderMap;
 
+        #[test]
+    fn add_typed_header() {
+        use super::LastModified;
+        let mut map = HeaderMap::new();
+        map.add(LastModified::from(SystemTime::now()));
+        assert!(map.get_one("last-modified").unwrap().contains("GMT"));
+    }
+
     #[test]
     fn case_insensitive_add_get() {
         let mut map = HeaderMap::new();

core/http/src/header/mod.rs

@@ -9,7 +9,18 @@ mod proxy_proto;
 pub use self::content_type::ContentType;
 pub use self::accept::{Accept, QMediaType};
 pub use self::media_type::MediaType;
-pub use self::header::{Header, HeaderMap};
+pub use self::header::{
+    Header, HeaderMap, AcceptRanges, AccessControlAllowCredentials,
+    AccessControlAllowHeaders, AccessControlAllowMethods, AccessControlAllowOrigin,
+    AccessControlExposeHeaders, AccessControlMaxAge, AccessControlRequestHeaders,
+    AccessControlRequestMethod, Age, Allow, CacheControl, Connection, ContentDisposition,
+    ContentEncoding, ContentLength, ContentLocation, ContentRange, Date, ETag, Expect,
+    Expires, IfMatch, IfModifiedSince, IfNoneMatch, IfRange, IfUnmodifiedSince,
+    LastModified, Origin, Pragma, Range, Referer, ReferrerPolicy, RetryAfter,
+    SecWebsocketAccept, SecWebsocketKey, SecWebsocketVersion, Server, StrictTransportSecurity,
+    Te, TransferEncoding, Upgrade, UserAgent, Vary, Authorization, ProxyAuthorization,
+    Credentials
+};
 pub use self::proxy_proto::ProxyProto;
 
 pub(crate) use self::media_type::Source;

core/lib/tests/typed-headers.rs

@@ -0,0 +1,30 @@
+#[macro_use]
+extern crate rocket;
+
+use std::time::{Duration, SystemTime};
+use rocket::http::Expires;
+
+#[derive(Responder)]
+struct MyResponse {
+    body: String,
+    expires: Expires,
+}
+
+#[get("/")]
+fn index() -> MyResponse {
+    let some_future_time =
+        SystemTime::UNIX_EPOCH.checked_add(Duration::from_secs(60 * 60 * 24 * 365 * 100)).unwrap();
+
+    MyResponse {
+        body: "Hello, world!".into(),
+        expires: Expires::from(some_future_time)
+    }
+}
+
+#[test]
+fn typed_header() {
+    let rocket = rocket::build().mount("/", routes![index]);
+    let client = rocket::local::blocking::Client::debug(rocket).unwrap();
+    let response = client.get("/").dispatch();
+    assert_eq!(response.headers().get_one("Expires").unwrap(), "Sat, 07 Dec 2069 00:00:00 GMT");
+}