fix(data): box TData since we don't know its type when fetching with uuid

Author: LizAinslie

crates/data/src/lib.rs

@@ -2,7 +2,9 @@
 
 pub mod registry;
 
+use std::ops::Deref;
 use bincode::{Decode, Encode};
+use bincode::config::Configuration;
 use bincode::error::{DecodeError, EncodeError};
 
 use bytes::{Bytes, BytesMut};
@@ -81,13 +83,13 @@ where
     }
 
     /// Decode a [TData] off a buffer
-    pub fn decode_from_bytes(&self, buf: &Bytes) -> Result<(TData, usize), DecodeError>
+    pub fn decode_from_bytes(&self, buf: &Bytes) -> Result<(Box<TData>, usize), DecodeError>
     where
-        TData : Decode + Sized,
+        TData : Decode,
     {
         let config = bincode::config::standard();
-        let res = bincode::decode_from_slice(buf, config)?;
-        Ok(res)
+        let res = bincode::decode_from_slice::<TData, Configuration>(buf, config)?;
+        Ok((Box::new(res.0), res.1))
     }
 
     /// Encode a [TData] onto a buffer
@@ -100,9 +102,7 @@ where
         Ok(len)
     }
 
-    pub fn handle(&self, obj: &TData)
-    where
-        TData : Sized,
+    pub fn handle(&self, obj: Box<&TData>)
     {
         for handler in &self.handlers {
             handler.handle(obj)
@@ -112,15 +112,15 @@ where
 
 pub trait DataHandler<TData> : DowncastSync + Send + Sync
 where
-    TData : Data + 'static
+    TData : Data + 'static + ?Sized
 {
-    fn handle(&self, obj: &TData);
+    fn handle(&self, obj: Box<&TData>);
 }
 
 impl_downcast!(sync DataHandler<TData> where TData : Data + 'static);
 
-impl<TData : Data, F: Fn(&TData) + Send + Sync + 'static> DataHandler<TData> for F {
-    fn handle(&self, obj: &TData) {
+impl<TData : Data + ?Sized, F: Fn(Box<&TData>) + Send + Sync + 'static> DataHandler<TData> for F {
+    fn handle(&self, obj: Box<&TData>) {
         self(obj)
     }
 }

crates/data/src/registry.rs

@@ -51,12 +51,11 @@ impl DataTypeRegistry {
     }
 
     /// Get the marshaller for [TData] based on a type [Uuid]
-    pub fn by_uuid<TData>(&self, uuid: &Uuid) -> Option<&DataType<TData>>
+    pub fn by_uuid(&self, uuid: &Uuid) -> Option<&DataType<dyn Data>>
     where
-        TData : Data + 'static,
     {
         let type_id = self.id_map.get(uuid)?;
-        unsafe { std::mem::transmute(self.types.get(type_id)) }
+        self.types.get(type_id)
     }
 
     // pub fn get_handler<TData, THandler>(&self, uuid: &Uuid) -> Option<&THandler>
@@ -90,7 +89,7 @@ mod tests {
     impl_data!(MyData, "9eddbf56-8cba-4962-9769-dcc84f1eefae");
 
     #[test]
-    fn test_registry() {
+    fn test_registry_fetch_by_type() {
         let mut registry = DataTypeRegistry::new();
 
         registry.register::<MyData>();
@@ -99,4 +98,14 @@ mod tests {
         assert!(got.is_some());
         assert_eq!(got.unwrap().get_id(), MyData::get_id_static());
     }
+
+    #[test]
+    fn test_registry_fetch_by_uuid() {
+        let mut registry = DataTypeRegistry::new();
+
+        registry.register::<MyData>();
+
+        let got = registry.by_uuid(&MyData::get_id_static());
+        assert!(got.is_some());
+    }
 }