handshake: add the ability to iterate over headers.

src/handshake/mod.rs

@@ -5,6 +5,7 @@ pub mod tls;
 
 use std::ascii::AsciiExt;
 use std::str::from_utf8;
+use std::slice;
 
 use base64;
 use bytes::Buf;
@@ -76,9 +77,15 @@ impl Headers {
 
     /// Get first header with the given name, if any.
     pub fn find_first(&self, name: &str) -> Option<&[u8]> {
-        self.data.iter()
-                .find(|&&(ref n, _)| n.eq_ignore_ascii_case(name))
-                .map(|&(_, ref v)| v.as_ref())
+        self.find(name).next()
+    }
+
+    /// Iterate over all headers with the given name.
+    pub fn find<'headers, 'name>(&'headers self, name: &'name str) -> HeadersIter<'name, 'headers> {
+        HeadersIter {
+            name: name,
+            iter: self.data.iter()
+        }
     }
 
     /// Check if the given header has the given value.
@@ -103,6 +110,25 @@ impl Headers {
 
 }
 
+/// The iterator over headers.
+pub struct HeadersIter<'name, 'headers> {
+    name: &'name str,
+    iter: slice::Iter<'headers, (String, Box<[u8]>)>,
+}
+
+impl<'name, 'headers> Iterator for HeadersIter<'name, 'headers> {
+    type Item = &'headers [u8];
+    fn next(&mut self) -> Option<Self::Item> {
+        while let Some(&(ref name, ref value)) = self.iter.next() {
+            if name.eq_ignore_ascii_case(self.name) {
+                return Some(value)
+            }
+        }
+        None
+    }
+}
+
+
 /// Trait to read HTTP parseable objects.
 trait Httparse: Sized {
     fn httparse(buf: &[u8]) -> Result<Option<(usize, Self)>>;
@@ -159,7 +185,10 @@ mod tests {
     #[test]
     fn headers() {
         const data: &'static [u8] =
-            b"Host: foo.com\r\nConnection: Upgrade\r\nUpgrade: websocket\r\n\r\n";
+            b"Host: foo.com\r\n\
+             Connection: Upgrade\r\n\
+             Upgrade: websocket\r\n\
+             \r\n";
         let mut inp = Cursor::new(data);
         let hdr = Headers::parse(&mut inp).unwrap().unwrap();
         assert_eq!(hdr.find_first("Host"), Some(&b"foo.com"[..]));
@@ -171,10 +200,29 @@ mod tests {
         assert!(hdr.header_is_ignore_case("upgrade", "Websocket"));
     }
 
+    #[test]
+    fn headers_iter() {
+        const data: &'static [u8] =
+            b"Host: foo.com\r\n\
+              Sec-WebSocket-Extensions: permessage-deflate\r\n\
+              Connection: Upgrade\r\n\
+              Sec-WebSocket-ExtenSIONS: permessage-unknown\r\n\
+              Upgrade: websocket\r\n\
+              \r\n";
+        let mut inp = Cursor::new(data);
+        let hdr = Headers::parse(&mut inp).unwrap().unwrap();
+        let mut iter = hdr.find("Sec-WebSocket-Extensions");
+        assert_eq!(iter.next(), Some(&b"permessage-deflate"[..]));
+        assert_eq!(iter.next(), Some(&b"permessage-unknown"[..]));
+        assert_eq!(iter.next(), None);
+    }
+
     #[test]
     fn headers_incomplete() {
         const data: &'static [u8] =
-            b"Host: foo.com\r\nConnection: Upgrade\r\nUpgrade: websocket\r\n";
+            b"Host: foo.com\r\n\
+              Connection: Upgrade\r\n\
+              Upgrade: websocket\r\n";
         let mut inp = Cursor::new(data);
         let hdr = Headers::parse(&mut inp).unwrap();
         assert!(hdr.is_none());