Decode debug_data in GOAWAY frames

Author: seanmonstar

src/frame/go_away.rs

@@ -1,18 +1,23 @@
-use crate::frame::{self, Error, Head, Kind, Reason, StreamId};
+use std::fmt;
+
+use bytes::{BufMut, Bytes};
 
-use bytes::BufMut;
+use crate::frame::{self, Error, Head, Kind, Reason, StreamId};
 
-#[derive(Debug, Clone, Copy, Eq, PartialEq)]
+#[derive(Clone, Eq, PartialEq)]
 pub struct GoAway {
     last_stream_id: StreamId,
     error_code: Reason,
+    #[allow(unused)]
+    debug_data: Bytes,
 }
 
 impl GoAway {
     pub fn new(last_stream_id: StreamId, reason: Reason) -> Self {
         GoAway {
             last_stream_id,
             error_code: reason,
+            debug_data: Bytes::new(),
         }
     }
 
@@ -24,17 +29,24 @@ impl GoAway {
         self.error_code
     }
 
+    #[cfg(feature = "unstable")]
+    pub fn debug_data(&self) -> &[u8] {
+        &self.debug_data
+    }
+
     pub fn load(payload: &[u8]) -> Result<GoAway, Error> {
         if payload.len() < 8 {
             return Err(Error::BadFrameSize);
         }
 
         let (last_stream_id, _) = StreamId::parse(&payload[..4]);
         let error_code = unpack_octets_4!(payload, 4, u32);
+        let debug_data = Bytes::from(&payload[8..]);
 
         Ok(GoAway {
             last_stream_id,
             error_code: error_code.into(),
+            debug_data,
         })
     }
 
@@ -52,3 +64,17 @@ impl<B> From<GoAway> for frame::Frame<B> {
         frame::Frame::GoAway(src)
     }
 }
+
+impl fmt::Debug for GoAway {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut builder = f.debug_struct("GoAway");
+        builder.field("error_code", &self.error_code);
+        builder.field("last_stream_id", &self.last_stream_id);
+
+        if !self.debug_data.is_empty() {
+            builder.field("debug_data", &self.debug_data);
+        }
+
+        builder.finish()
+    }
+}

tests/h2-tests/tests/codec_read.rs

@@ -214,3 +214,26 @@ async fn update_max_frame_len_at_rest() {
         "frame with invalid size"
     );
 }
+
+#[tokio::test]
+async fn read_goaway_with_debug_data() {
+    let mut codec = raw_codec! {
+        read => [
+            // head
+            0, 0, 22, 7, 0, 0, 0, 0, 0,
+            // last_stream_id
+            0, 0, 0, 1,
+            // error_code
+            0, 0, 0, 11,
+            // debug_data
+            "too_many_pings",
+        ];
+    };
+
+    let data = poll_frame!(GoAway, codec);
+    assert_eq!(data.reason(), Reason::ENHANCE_YOUR_CALM);
+    assert_eq!(data.last_stream_id(), 1);
+    assert_eq!(data.debug_data(), b"too_many_pings");
+
+    assert_closed!(codec);
+}