sync messages are bytes outside the session

SyncPayload is now an opaque byte container in transport.
SyncSession::generate returns the encoded payload, state::decode_sync(&payload)
decodes it off the document lock (as before), and receive takes the decoded
message, which is a type only the session can open.  transport/mod.rs no longer
imports Automerge.

1 files changed, 4 insertions, 15 deletions

diff --git a/src/transport/mod.rs b/src/transport/mod.rs
index c10e0d8..cef31ff 100644
--- a/src/transport/mod.rs
+++ b/src/transport/mod.rs
@@ -1,6 +1,5 @@
 use anyhow::Result;
 use async_trait::async_trait;
-use automerge::sync::Message;
 use serde::{Deserialize, Serialize};
 use sha2::{Digest, Sha256};
 use std::boxed::Box;
@@ -681,23 +680,13 @@ impl DeltaSpec {
     }
 }
 
-/// An Automerge sync message in Automerge's own encoding. Decoded only where it is
-/// applied (`decode`), after the sender proved to be a member and off the consumer: a
-/// large message from anyone else costs nothing but its bytes.
+/// A sync message as the document's engine encodes it (`state::session`): bytes to the
+/// transports. Decoded only where it is applied (`state::decode_sync`), after the sender
+/// proved to be a member and off the consumer: a large message from anyone else costs
+/// nothing but its bytes.
 #[derive(Clone)]
 pub(crate) struct SyncPayload(pub(crate) bytes::Bytes);
 
-impl SyncPayload {
-    pub(crate) fn encode(message: Message) -> Self {
-        Self(message.encode().into())
-    }
-
-    pub(crate) fn decode(&self) -> Result<Message> {
-        Message::decode(&self.0)
-            .map_err(|error| anyhow::anyhow!("Automerge decode failed: {error:?}"))
-    }
-}
-
 /// Sizes instead of contents: logged messages stay short.
 impl std::fmt::Debug for SyncPayload {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {