feat(headers): Add Accept-Ranges header field

src/header/common/accept_ranges.rs

@@ -0,0 +1,71 @@
+use std::fmt::{self, Display};
+use std::str::FromStr;
+
+header! {
+    #[doc="`Accept-Ranges` header, defined in"]
+    #[doc="[RFC7233](http://tools.ietf.org/html/rfc7233#section-2.3)"]
+    #[doc=""]
+    #[doc="The `Accept-Ranges` header field allows a server to indicate that it"]
+    #[doc="supports range requests for the target resource."]
+    #[doc=""]
+    #[doc="# ABNF"]
+    #[doc="```plain"]
+    #[doc="Accept-Ranges     = acceptable-ranges"]
+    #[doc="acceptable-ranges = 1#range-unit / \"none\""]
+    #[doc=""]
+    #[doc="# Example values"]
+    #[doc="* `bytes`"]
+    #[doc="* `none`"]
+    #[doc="```"]
+    (AcceptRanges, "Accept-Ranges") => (RangeUnit)+
+
+    test_acccept_ranges {
+        test_header!(test1, vec![b"bytes"]);
+        test_header!(test2, vec![b"none"]);
+    }
+}
+
+/// Range Units, described in [RFC7233](http://tools.ietf.org/html/rfc7233#section-2)
+///
+/// A representation can be partitioned into subranges according to
+/// various structural units, depending on the structure inherent in the
+/// representation's media type.
+///
+/// # ABNF
+/// ```plain
+/// range-unit       = bytes-unit / other-range-unit
+/// bytes-unit       = "bytes"
+/// other-range-unit = token
+/// ```
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub enum RangeUnit {
+    /// Indicating byte-range requests are supported.
+    Bytes,
+    /// Reserved as keyword, indicating no ranges are supported.
+    None,
+    /// The given range unit is not registered at IANA.
+    Unregistered(String),
+}
+
+
+impl FromStr for RangeUnit {
+    type Err = ();
+    fn from_str(s: &str) -> Result<Self, ()> {
+        match s {
+            "bytes" => Ok(RangeUnit::Bytes),
+            "none" => Ok(RangeUnit::None),
+            // FIXME: Check if s is really a Token
+            _ => Ok(RangeUnit::Unregistered(s.to_string())),
+        }
+    }
+}
+
+impl Display for RangeUnit {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            RangeUnit::Bytes => f.write_str("bytes"),
+            RangeUnit::None => f.write_str("none"),
+            RangeUnit::Unregistered(ref x) => f.write_str(&x),
+        }
+    }
+}

src/header/common/mod.rs

@@ -16,6 +16,7 @@ pub use self::access_control_request_method::AccessControlRequestMethod;
 pub use self::accept_charset::AcceptCharset;
 pub use self::accept_encoding::AcceptEncoding;
 pub use self::accept_language::AcceptLanguage;
+pub use self::accept_ranges::AcceptRanges;
 pub use self::allow::Allow;
 pub use self::authorization::{Authorization, Scheme, Basic};
 pub use self::cache_control::{CacheControl, CacheDirective};
@@ -302,6 +303,7 @@ mod access_control_request_method;
 mod accept_charset;
 mod accept_encoding;
 mod accept_language;
+mod accept_ranges;
 mod allow;
 mod authorization;
 mod cache_control;