[hyperactor] Serialized: multipart support

Differential Revision: [D80447202](https://our.internmc.facebook.com/intern/diff/D80447202/)

ghstack-source-id: 303699219
Pull Request resolved: #905

Author: mariusae

hyperactor/src/data.rs

@@ -296,7 +296,7 @@ macro_rules! register_type {
 enum Encoded {
     Bincode(serde_bytes::ByteBuf),
     Json(serde_bytes::ByteBuf),
-    // todo: multipart
+    Multipart(serde_multipart::Message),
 }
 
 impl Encoded {
@@ -305,6 +305,7 @@ impl Encoded {
         match &self {
             Encoded::Bincode(data) => data.len(),
             Encoded::Json(data) => data.len(),
+            Encoded::Multipart(message) => message.len(),
         }
     }
 
@@ -313,6 +314,7 @@ impl Encoded {
         match &self {
             Encoded::Bincode(data) => data.is_empty(),
             Encoded::Json(data) => data.is_empty(),
+            Encoded::Multipart(message) => message.is_empty(),
         }
     }
 
@@ -321,6 +323,14 @@ impl Encoded {
         match &self {
             Encoded::Bincode(data) => crc32fast::hash(data),
             Encoded::Json(data) => crc32fast::hash(data),
+            Encoded::Multipart(message) => {
+                let mut hasher = crc32fast::Hasher::new();
+                hasher.update(message.body().as_ref());
+                for part in message.parts() {
+                    hasher.update(part.as_ref());
+                }
+                hasher.finalize()
+            }
         }
     }
 }
@@ -330,6 +340,7 @@ impl std::fmt::Debug for Encoded {
         match self {
             Encoded::Bincode(data) => write!(f, "Encoded::Bincode({})", HexFmt(data.as_slice())),
             Encoded::Json(data) => write!(f, "Encoded::Json({})", HexFmt(data.as_slice())),
+            Encoded::Multipart(message) => todo!(), //write!(f, "Encoded::Multipart({})", HexFmt(data.as_slice())),
         }
     }
 }
@@ -386,14 +397,17 @@ impl Serialized {
         match &self.encoded {
             Encoded::Bincode(data) => bincode::deserialize(data).map_err(anyhow::Error::from),
             Encoded::Json(data) => serde_json::from_slice(data).map_err(anyhow::Error::from),
+            Encoded::Multipart(message) => {
+                serde_multipart::deserialize_bincode(message.clone()).map_err(anyhow::Error::from)
+            }
         }
     }
 
     /// Transcode the serialized value to JSON. This operation will succeed if the type hash
     /// is embedded in the value, and the corresponding type is available in this binary.
     pub fn transcode_to_json(self) -> Result<Self, Self> {
         match self.encoded {
-            Encoded::Bincode(_) => {
+            Encoded::Bincode(_) | Encoded::Multipart(_) => {
                 let json_value = match self.dump() {
                     Ok(json_value) => json_value,
                     Err(_) => return Err(self),
@@ -425,6 +439,10 @@ impl Serialized {
                 typeinfo.dump(self.clone())
             }
             Encoded::Json(data) => serde_json::from_slice(data).map_err(anyhow::Error::from),
+            Encoded::Multipart(_) => {
+                // TODO: implement typeinfo.dump_multipart
+                anyhow::bail!("dumping multipart-encoded values is not yet supported")
+            }
         }
     }