feat(headers): Add Access-Control-Expose-Headers

Fix #673

src/header/common/access_control_expose_headers.rs

@@ -0,0 +1,60 @@
+use unicase::UniCase;
+
+header! {
+    /// `Access-Control-Expose-Headers` header, part of
+    /// [CORS](http://www.w3.org/TR/cors/#access-control-expose-headers-response-header)
+    ///
+    /// The Access-Control-Expose-Headers header indicates which headers are safe to expose to the
+    /// API of a CORS API specification.
+    ///
+    /// # ABNF
+    /// ```plain
+    /// Access-Control-Expose-Headers = "Access-Control-Expose-Headers" ":" #field-name
+    /// ```
+    ///
+    /// # Example values
+    /// * `ETag, Content-Length`
+    ///
+    /// # Examples
+    /// ```
+    /// # extern crate hyper;
+    /// # extern crate unicase;
+    /// # fn main() {
+    /// // extern crate unicase;
+    ///
+    /// use hyper::header::{Headers, AccessControlExposeHeaders};
+    /// use unicase::UniCase;
+    ///
+    /// let mut headers = Headers::new();
+    /// headers.set(
+    ///     AccessControlExposeHeaders(vec![
+    ///         UniCase("etag".to_owned()),
+    ///         UniCase("content-length".to_owned())
+    ///     ])
+    /// );
+    /// # }
+    /// ```
+    /// ```
+    /// # extern crate hyper;
+    /// # extern crate unicase;
+    /// # fn main() {
+    /// // extern crate unicase;
+    ///
+    /// use hyper::header::{Headers, AccessControlExposeHeaders};
+    /// use unicase::UniCase;
+    ///
+    /// let mut headers = Headers::new();
+    /// headers.set(
+    ///     AccessControlExposeHeaders(vec![
+    ///         UniCase("etag".to_owned()),
+    ///         UniCase("content-length".to_owned())
+    ///     ])
+    /// );
+    /// # }
+    /// ```
+    (AccessControlExposeHeaders, "Access-Control-Expose-Headers") => (UniCase<String>)*
+
+    test_access_control_expose_headers {
+        test_header!(test1, vec![b"etag, content-length"]);
+    }
+}

src/header/common/mod.rs

@@ -10,6 +10,7 @@ pub use self::accept::Accept;
 pub use self::access_control_allow_headers::AccessControlAllowHeaders;
 pub use self::access_control_allow_methods::AccessControlAllowMethods;
 pub use self::access_control_allow_origin::AccessControlAllowOrigin;
+pub use self::access_control_expose_headers::AccessControlExposeHeaders;
 pub use self::access_control_max_age::AccessControlMaxAge;
 pub use self::access_control_request_headers::AccessControlRequestHeaders;
 pub use self::access_control_request_method::AccessControlRequestMethod;
@@ -355,6 +356,7 @@ mod accept;
 mod access_control_allow_headers;
 mod access_control_allow_methods;
 mod access_control_allow_origin;
+mod access_control_expose_headers;
 mod access_control_max_age;
 mod access_control_request_headers;
 mod access_control_request_method;