feat(headers): add origin header

Add an Origin header so users may properly send CORS requests

Closes #651

src/header/common/origin.rs

@@ -0,0 +1,111 @@
+use header::{Header, Host};
+use std::fmt;
+use std::str::FromStr;
+use header::parsing::from_one_raw_str;
+
+/// The `Origin` header.
+///
+/// The `Origin` header is a version of the `Referer` header that is used for all HTTP fetches and `POST`s whose CORS flag is set.
+/// This header is often used to inform recipients of the security context of where the request was initiated.
+///
+///
+/// Following the spec, https://fetch.spec.whatwg.org/#origin-header, the value of this header is composed of
+/// a String (scheme), header::Host (host/port)
+///
+/// # Examples
+/// ```
+/// use hyper::header::{Headers, Origin};
+///
+/// let mut headers = Headers::new();
+/// headers.set(
+///     Origin::new("http", "hyper.rs", None)
+/// );
+/// ```
+/// ```
+/// use hyper::header::{Headers, Origin};
+///
+/// let mut headers = Headers::new();
+/// headers.set(
+///     Origin::new("https", "wikipedia.org", Some(443))
+/// );
+/// ```
+
+#[derive(Clone, Debug)]
+pub struct Origin {
+    /// The scheme, such as http or https
+    pub scheme: String,
+    /// The host, such as Host{hostname: "hyper.rs".to_owned(), port: None}
+    pub host: Host,
+}
+
+impl Origin {
+    /// Creates a new `Origin` header.
+    pub fn new<S: Into<String>, H: Into<String>>(scheme: S, hostname: H, port: Option<u16>) -> Origin{
+        Origin {
+            scheme: scheme.into(),
+            host: Host {
+                hostname: hostname.into(),
+                port: port
+            }
+        }
+    }
+}
+
+impl Header for Origin {
+    fn header_name() -> &'static str {
+        static NAME: &'static str = "Origin";
+        NAME
+    }
+
+    fn parse_header(raw: &[Vec<u8>]) -> ::Result<Origin> {
+        from_one_raw_str(raw)
+    }
+
+    fn fmt_header(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}://{}", self.scheme, self.host)
+    }
+}
+
+impl FromStr for Origin {
+    type Err = ::Error;
+
+    fn from_str(s: &str) -> ::Result<Origin> {
+        let idx = match s.find("://") {
+            Some(idx) => idx,
+            None => return Err(::Error::Header)
+        };
+        // idx + 3 because thats how long "://" is
+        let (scheme, etc) = (&s[..idx], &s[idx + 3..]);
+        let host = try!(Host::from_str(etc));
+
+
+        Ok(Origin{
+            scheme: scheme.to_owned(),
+            host: host
+        })
+    }
+}
+
+impl PartialEq for Origin {
+    fn eq(&self, other: &Origin) -> bool {
+        self.scheme == other.scheme && self.host == other.host
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::Origin;
+    use header::Header;
+
+    #[test]
+    fn test_origin() {
+        let origin = Header::parse_header([b"http://foo.com".to_vec()].as_ref());
+        assert_eq!(origin.ok(), Some(Origin::new("http", "foo.com", None)));
+
+        let origin = Header::parse_header([b"https://foo.com:443".to_vec()].as_ref());
+        assert_eq!(origin.ok(), Some(Origin::new("https", "foo.com", Some(443))));
+    }
+}
+
+bench_header!(bench, Origin, { vec![b"https://foo.com".to_vec()] });