Fix: Move WS error handling (#174)

Moves all WS handling of unexpected payloads into the stream to prevent code duplication.

This also prevents non-{Hello,Resumed,Ready} messages from causing a handshake failure, as it seems Discord do not prevent such messages from appearing.

---------

Co-authored-by: Kyle Simpson <kyleandrew.simpson@gmail.com>

src/ws.rs

@@ -94,19 +94,16 @@ pub(crate) fn convert_ws_message(message: Option<Message>) -> Result<Option<Even
     Ok(match message {
         // SAFETY:
         // simd-json::serde::from_str may leave an &mut str in a non-UTF state on failure.
-        // The below is safe as we have taken ownership of the inner `String`, and don't
-        // access it as a `str`/`String` or return it if failure occurs.
+        // The below is safe as we have taken ownership of the inner `String`, and if
+        // failure occurs we forcibly re-validate its contents before logging.
         Some(Message::Text(mut payload)) =>
-            match unsafe { crate::json::from_str(payload.as_mut_str()) } {
-                Ok(event) => Some(event),
-                Err(why) => {
-                    debug!(
-                        "Could not deserialize websocket event, payload: {}, error: {}",
-                        payload, why
-                    );
-                    None
-                },
-            },
+            (unsafe { crate::json::from_str(payload.as_mut_str()) })
+                .map_err(|e| {
+                    let safe_payload = String::from_utf8_lossy(payload.as_bytes());
+                    debug!("Unexpected JSON: {e}. Payload: {safe_payload}");
+                    e
+                })
+                .ok(),
         Some(Message::Binary(bytes)) => {
             return Err(Error::UnexpectedBinaryMessage(bytes));
         },