feat: add cache-status and cdn-cache-control header name constants (#583)

Docs include pointers to the relevant RFCs, as these are not in the base HTTP semantics spec.

Author: acfoltzer

CHANGELOG.md

@@ -1,3 +1,7 @@
+# Unreleased
+
+* Add `HeaderName` constants for `cache-status` and `cdn-cache-control`.
+
 # 0.2.8 (June 6, 2022)
 
 * Fix internal usage of uninitialized memory to use `MaybeUninit` inside `HeaderName`.

benches/src/header_map/basic.rs

@@ -536,6 +536,8 @@ const STD: &'static [HeaderName] = &[
     ALT_SVC,
     AUTHORIZATION,
     CACHE_CONTROL,
+    CACHE_STATUS,
+    CDN_CACHE_CONTROL,
     CONNECTION,
     CONTENT_DISPOSITION,
     CONTENT_ENCODING,

src/header/mod.rs

@@ -101,6 +101,8 @@ pub use self::name::{
     ALT_SVC,
     AUTHORIZATION,
     CACHE_CONTROL,
+    CACHE_STATUS,
+    CDN_CACHE_CONTROL,
     CONNECTION,
     CONTENT_DISPOSITION,
     CONTENT_ENCODING,

src/header/name.rs

@@ -345,6 +345,18 @@ standard_headers! {
     /// response.
     (CacheControl, CACHE_CONTROL, b"cache-control");
 
+    /// Indicates how caches have handled a response and its corresponding request.
+    ///
+    /// See [RFC 9211](https://www.rfc-editor.org/rfc/rfc9211.html).
+    (CacheStatus, CACHE_STATUS, b"cache-status");
+
+    /// Specifies directives that allow origin servers to control the behavior of CDN caches
+    /// interposed between them and clients separately from other caches that might handle the
+    /// response.
+    ///
+    /// See [RFC 9213](https://www.rfc-editor.org/rfc/rfc9213.html).
+    (CdnCacheControl, CDN_CACHE_CONTROL, b"cdn-cache-control");
+
     /// Controls whether or not the network connection stays open after the
     /// current transaction finishes.
     ///

tests/header_map.rs

@@ -346,6 +346,8 @@ const STD: &'static [HeaderName] = &[
     ALT_SVC,
     AUTHORIZATION,
     CACHE_CONTROL,
+    CACHE_STATUS,
+    CDN_CACHE_CONTROL,
     CONNECTION,
     CONTENT_DISPOSITION,
     CONTENT_ENCODING,

tests/header_map_fuzz.rs

@@ -282,6 +282,8 @@ fn gen_header_name(g: &mut StdRng) -> HeaderName {
         header::ALT_SVC,
         header::AUTHORIZATION,
         header::CACHE_CONTROL,
+        header::CACHE_STATUS,
+        header::CDN_CACHE_CONTROL,
         header::CONNECTION,
         header::CONTENT_DISPOSITION,
         header::CONTENT_ENCODING,