feat(http): allow specifying custom body streams

src/http/mod.rs

@@ -133,6 +133,23 @@ pub trait Http1Transaction {
 
 type ParseResult<T> = ::Result<Option<(MessageHead<T>, usize)>>;
 
+struct DebugTruncate<'a>(&'a [u8]);
+
+impl<'a> fmt::Debug for DebugTruncate<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let bytes = self.0;
+        if bytes.len() > 32 {
+            try!(f.write_str("["));
+            for byte in &bytes[..32] {
+                try!(write!(f, "{:?}, ", byte));
+            }
+            write!(f, "... {}]", bytes.len())
+        } else {
+            fmt::Debug::fmt(bytes, f)
+        }
+    }
+}
+
 #[test]
 fn test_should_keep_alive() {
     let mut headers = Headers::new();