initial work on netapp streams - garage side

Cargo.lock

@@ -939,6 +939,7 @@ dependencies = [
  "garage_table 0.7.0",
  "garage_util 0.7.0",
  "hex",
+ "netapp 0.4.4",
  "opentelemetry",
  "rand 0.8.5",
  "rmp-serde 0.15.5",
@@ -1136,6 +1137,7 @@ dependencies = [
 name = "garage_util"
 version = "0.7.0"
 dependencies = [
+ "async-trait",
  "blake2",
  "chrono",
  "err-derive 0.3.1",
@@ -1851,8 +1853,6 @@ dependencies = [
 [[package]]
 name = "netapp"
 version = "0.4.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c6419a4b836774192e13fedb05c0e5f414ee8df9ca0c467456a0bacde06c29ee"
 dependencies = [
  "arc-swap",
  "async-trait",
@@ -1866,6 +1866,7 @@ dependencies = [
  "log",
  "opentelemetry",
  "opentelemetry-contrib",
+ "pin-project 1.0.10",
  "rand 0.5.6",
  "rmp-serde 0.14.4",
  "serde",

Cargo.toml

@@ -16,3 +16,6 @@ lto = "off"
 
 [profile.release]
 debug = true
+
+[patch.crates-io]
+netapp = { path = "../netapp" }

src/api/error.rs

@@ -1,4 +1,5 @@
 use std::convert::TryInto;
+use std::sync::Arc;
 
 use err_derive::Error;
 use hyper::header::HeaderValue;
@@ -15,7 +16,7 @@ pub enum Error {
 	// Category: internal error
 	/// Error related to deeper parts of Garage
 	#[error(display = "Internal error: {}", _0)]
-	InternalError(#[error(source)] GarageError),
+	InternalError(Arc<GarageError>),
 
 	/// Error related to Hyper
 	#[error(display = "Internal error (Hyper error): {}", _0)]
@@ -109,6 +110,12 @@ pub enum Error {
 	NotImplemented(String),
 }
 
+impl From<GarageError> for Error {
+	fn from(err: GarageError) -> Self {
+		Self::InternalError(Arc::new(err))
+	}
+}
+
 impl From<roxmltree::Error> for Error {
 	fn from(err: roxmltree::Error) -> Self {
 		Self::InvalidXml(format!("{}", err))
@@ -145,14 +152,13 @@ impl Error {
 			Error::PreconditionFailed => StatusCode::PRECONDITION_FAILED,
 			Error::Forbidden(_) => StatusCode::FORBIDDEN,
 			Error::NotAcceptable(_) => StatusCode::NOT_ACCEPTABLE,
-			Error::InternalError(
+			Error::InternalError(e) => match **e {
 				GarageError::Timeout
 				| GarageError::RemoteError(_)
-				| GarageError::Quorum(_, _, _, _),
-			) => StatusCode::SERVICE_UNAVAILABLE,
-			Error::InternalError(_) | Error::Hyper(_) | Error::Http(_) => {
-				StatusCode::INTERNAL_SERVER_ERROR
-			}
+				| GarageError::Quorum(_, _, _, _) => StatusCode::SERVICE_UNAVAILABLE,
+				_ => StatusCode::INTERNAL_SERVER_ERROR,
+			},
+			Error::Hyper(_) | Error::Http(_) => StatusCode::INTERNAL_SERVER_ERROR,
 			Error::InvalidRange(_) => StatusCode::RANGE_NOT_SATISFIABLE,
 			Error::NotImplemented(_) => StatusCode::NOT_IMPLEMENTED,
 			_ => StatusCode::BAD_REQUEST,
@@ -173,12 +179,13 @@ impl Error {
 			Error::Forbidden(_) => "AccessDenied",
 			Error::AuthorizationHeaderMalformed(_) => "AuthorizationHeaderMalformed",
 			Error::NotImplemented(_) => "NotImplemented",
-			Error::InternalError(
+			Error::InternalError(e) => match **e {
 				GarageError::Timeout
 				| GarageError::RemoteError(_)
-				| GarageError::Quorum(_, _, _, _),
-			) => "ServiceUnavailable",
-			Error::InternalError(_) | Error::Hyper(_) | Error::Http(_) => "InternalError",
+				| GarageError::Quorum(_, _, _, _) => "ServiceUnavailable",
+				_ => "InternalError",
+			},
+			Error::Hyper(_) | Error::Http(_) => "InternalError",
 			_ => "InvalidRequest",
 		}
 	}
@@ -262,10 +269,8 @@ where
 	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, Error> {
 		match self {
 			Ok(x) => Ok(x),
-			Err(e) => Err(Error::InternalError(GarageError::Message(format!(
-				"{}: {}",
-				reason.as_ref(),
-				e
+			Err(e) => Err(Error::InternalError(Arc::new(GarageError::Message(
+				format!("{}: {}", reason.as_ref(), e),
 			)))),
 		}
 	}
@@ -276,9 +281,9 @@ impl<T> OkOrInternalError for Option<T> {
 	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, Error> {
 		match self {
 			Some(x) => Ok(x),
-			None => Err(Error::InternalError(GarageError::Message(
+			None => Err(Error::InternalError(Arc::new(GarageError::Message(
 				reason.as_ref().to_string(),
-			))),
+			)))),
 		}
 	}
 }

src/block/Cargo.toml

@@ -17,6 +17,7 @@ path = "lib.rs"
 garage_rpc = { version = "0.7.0", path = "../rpc" }
 garage_util = { version = "0.7.0", path = "../util" }
 garage_table = { version = "0.7.0", path = "../table" }
+netapp = "0.4"
 
 opentelemetry = "0.17"
 

src/block/block.rs

@@ -1,16 +1,15 @@
-use serde::{Deserialize, Serialize};
 use zstd::stream::{decode_all as zstd_decode, Encoder};
 
 use garage_util::data::*;
 use garage_util::error::*;
 
 /// A possibly compressed block of data
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug)]
 pub enum DataBlock {
 	/// Uncompressed data
-	Plain(#[serde(with = "serde_bytes")] Vec<u8>),
+	Plain(Vec<u8>),
 	/// Data compressed with zstd
-	Compressed(#[serde(with = "serde_bytes")] Vec<u8>),
+	Compressed(Vec<u8>),
 }
 
 impl DataBlock {

src/block/manager.rs

@@ -6,8 +6,12 @@ use std::time::Duration;
 use async_trait::async_trait;
 use serde::{Deserialize, Serialize};
 
+use netapp::endpoint::SerializeMessage;
+use netapp::util::AssociatedStream;
+
 use futures::future::*;
 use futures::select;
+use futures::StreamExt;
 use tokio::fs;
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::sync::{watch, Mutex, Notify};
@@ -56,7 +60,7 @@ const RESYNC_RETRY_DELAY_MAX_BACKOFF_POWER: u64 = 6;
 pub(crate) const BLOCK_GC_DELAY: Duration = Duration::from_secs(600);
 
 /// RPC messages used to share blocks of data between nodes
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug)]
 pub enum BlockRpc {
 	Ok,
 	/// Message to ask for a block of data, by hash
@@ -73,10 +77,74 @@ pub enum BlockRpc {
 	NeedBlockReply(bool),
 }
 
+#[derive(Debug, Serialize, Deserialize)]
+pub enum BlockRpcSer {
+	Ok,
+	GetBlock(Hash),
+	PutBlock {
+		hash: Hash,
+		compressed: bool,
+		len: usize,
+	},
+	NeedBlockQuery(Hash),
+	NeedBlockReply(bool),
+}
+
 impl Rpc for BlockRpc {
 	type Response = Result<BlockRpc, Error>;
 }
 
+#[async_trait]
+impl SerializeMessage for BlockRpc {
+	type SerializableSelf = BlockRpcSer;
+
+	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<AssociatedStream>) {
+		let ser_self = match self {
+			BlockRpc::Ok => BlockRpcSer::Ok,
+			BlockRpc::GetBlock(h) => BlockRpcSer::GetBlock(*h),
+			BlockRpc::PutBlock { hash, data } => {
+				let buf = data.inner_buffer().to_vec();
+				let ser_self = BlockRpcSer::PutBlock {
+					hash: *hash,
+					compressed: data.is_compressed(),
+					len: buf.len(),
+				};
+				let stream = Box::pin(futures::stream::once(async move { buf }));
+				return (ser_self, Some(stream));
+			}
+			BlockRpc::NeedBlockQuery(h) => BlockRpcSer::NeedBlockQuery(*h),
+			BlockRpc::NeedBlockReply(b) => BlockRpcSer::NeedBlockReply(*b),
+		};
+		(ser_self, None)
+	}
+
+	async fn deserialize_msg(self_ser: Self::SerializableSelf, stream: AssociatedStream) -> Self {
+		let de_self = match self_ser {
+			BlockRpcSer::Ok => BlockRpc::Ok,
+			BlockRpcSer::GetBlock(h) => BlockRpc::GetBlock(h),
+			BlockRpcSer::PutBlock {
+				hash,
+				compressed,
+				len,
+			} => {
+				// TODO this is very useless. It should store the stream so it can be accessed as a
+				// stream instead
+				let raw_data = stream.concat().await;
+				assert_eq!(len, raw_data.len());
+				let data = if compressed {
+					DataBlock::Compressed(raw_data)
+				} else {
+					DataBlock::Plain(raw_data)
+				};
+				BlockRpc::PutBlock { hash, data }
+			}
+			BlockRpcSer::NeedBlockQuery(h) => BlockRpc::NeedBlockQuery(h),
+			BlockRpcSer::NeedBlockReply(b) => BlockRpc::NeedBlockReply(b),
+		};
+		de_self
+	}
+}
+
 /// The block manager, handling block exchange between nodes, and block storage on local node
 pub struct BlockManager {
 	/// Replication strategy, allowing to find on which node blocks should be located
@@ -694,7 +762,7 @@ impl BlockManager {
 						}
 					}
 					m => {
-						return Err(Error::unexpected_rpc_message(m));
+						return Err(Error::unexpected_rpc_message(m.serialize_msg().0));
 					}
 				}
 			}
@@ -836,7 +904,7 @@ impl EndpointHandler<BlockRpc> for BlockManager {
 			BlockRpc::PutBlock { hash, data } => self.write_block(hash, data).await,
 			BlockRpc::GetBlock(h) => self.read_block(h).await,
 			BlockRpc::NeedBlockQuery(h) => self.need_block(h).await.map(BlockRpc::NeedBlockReply),
-			m => Err(Error::unexpected_rpc_message(m)),
+			m => Err(Error::unexpected_rpc_message(m.serialize_msg().0)),
 		}
 	}
 }

src/garage/admin.rs

@@ -29,7 +29,7 @@ use crate::repair::Repair;
 
 pub const ADMIN_RPC_PATH: &str = "garage/admin_rpc.rs/Rpc";
 
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum AdminRpc {
 	BucketOperation(BucketOperation),
 	KeyOperation(KeyOperation),
@@ -49,6 +49,8 @@ impl Rpc for AdminRpc {
 	type Response = Result<AdminRpc, Error>;
 }
 
+impl AutoSerialize for AdminRpc {}
+
 pub struct AdminRpcHandler {
 	garage: Arc<Garage>,
 	endpoint: Arc<Endpoint<AdminRpc, Self>>,

src/garage/cli/structs.rs

@@ -138,7 +138,7 @@ pub struct RevertLayoutOpt {
 	pub(crate) version: Option<u64>,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub enum BucketOperation {
 	/// List buckets
 	#[structopt(name = "list")]
@@ -177,7 +177,7 @@ pub enum BucketOperation {
 	Website(WebsiteOpt),
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct WebsiteOpt {
 	/// Create
 	#[structopt(long = "allow")]
@@ -199,13 +199,13 @@ pub struct WebsiteOpt {
 	pub error_document: Option<String>,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct BucketOpt {
 	/// Bucket name
 	pub name: String,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct DeleteBucketOpt {
 	/// Bucket name
 	pub name: String,
@@ -215,7 +215,7 @@ pub struct DeleteBucketOpt {
 	pub yes: bool,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct AliasBucketOpt {
 	/// Existing bucket name (its alias in global namespace or its full hex uuid)
 	pub existing_bucket: String,
@@ -228,7 +228,7 @@ pub struct AliasBucketOpt {
 	pub local: Option<String>,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct UnaliasBucketOpt {
 	/// Bucket name
 	pub name: String,
@@ -238,7 +238,7 @@ pub struct UnaliasBucketOpt {
 	pub local: Option<String>,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct PermBucketOpt {
 	/// Access key name or ID
 	#[structopt(long = "key")]
@@ -261,7 +261,7 @@ pub struct PermBucketOpt {
 	pub bucket: String,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub enum KeyOperation {
 	/// List keys
 	#[structopt(name = "list")]
@@ -296,20 +296,20 @@ pub enum KeyOperation {
 	Import(KeyImportOpt),
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyOpt {
 	/// ID or name of the key
 	pub key_pattern: String,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyNewOpt {
 	/// Name of the key
 	#[structopt(long = "name", default_value = "Unnamed key")]
 	pub name: String,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyRenameOpt {
 	/// ID or name of the key
 	pub key_pattern: String,
@@ -318,7 +318,7 @@ pub struct KeyRenameOpt {
 	pub new_name: String,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyDeleteOpt {
 	/// ID or name of the key
 	pub key_pattern: String,
@@ -328,7 +328,7 @@ pub struct KeyDeleteOpt {
 	pub yes: bool,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyPermOpt {
 	/// ID or name of the key
 	pub key_pattern: String,
@@ -338,7 +338,7 @@ pub struct KeyPermOpt {
 	pub create_bucket: bool,
 }
 
-#[derive(Serialize, Deserialize, StructOpt, Debug)]
+#[derive(Serialize, Deserialize, StructOpt, Debug, Clone)]
 pub struct KeyImportOpt {
 	/// Access key ID
 	pub key_id: String,

src/model/helper/error.rs

@@ -1,20 +1,29 @@
 use err_derive::Error;
 use serde::{Deserialize, Serialize};
+use std::sync::Arc;
 
 use garage_util::error::Error as GarageError;
 
-#[derive(Debug, Error, Serialize, Deserialize)]
+#[derive(Debug, Error, Serialize, Deserialize, Clone)]
 pub enum Error {
 	#[error(display = "Internal error: {}", _0)]
-	Internal(#[error(source)] GarageError),
+	Internal(Arc<GarageError>),
 
 	#[error(display = "Bad request: {}", _0)]
 	BadRequest(String),
 }
 
+impl From<GarageError> for Error {
+	fn from(e: GarageError) -> Error {
+		Error::Internal(Arc::new(e))
+	}
+}
+
+impl netapp::endpoint::AutoSerialize for Error {}
+
 impl From<netapp::error::Error> for Error {
 	fn from(e: netapp::error::Error) -> Self {
-		Error::Internal(GarageError::Netapp(e))
+		Error::Internal(Arc::new(GarageError::Netapp(e)))
 	}
 }
 

src/rpc/rpc_helper.rs

@@ -15,7 +15,9 @@ use opentelemetry::{
 	Context,
 };
 
-pub use netapp::endpoint::{Endpoint, EndpointHandler, Message as Rpc};
+pub use netapp::endpoint::{
+	AutoSerialize, Endpoint, EndpointHandler, Message as Rpc, SerializeMessage,
+};
 use netapp::peering::fullmesh::FullMeshPeeringStrategy;
 pub use netapp::proto::*;
 pub use netapp::{NetApp, NodeID};
@@ -118,7 +120,9 @@ impl RpcHelper {
 	) -> Result<S, Error>
 	where
 		M: Rpc<Response = Result<S, Error>>,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M>,
+		S: Send,
 	{
 		self.call_arc(endpoint, to, Arc::new(msg), strat).await
 	}
@@ -132,7 +136,9 @@ impl RpcHelper {
 	) -> Result<S, Error>
 	where
 		M: Rpc<Response = Result<S, Error>>,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M>,
+		S: Send,
 	{
 		let metric_tags = [
 			KeyValue::new("rpc_endpoint", endpoint.path().to_string()),
@@ -140,7 +146,9 @@ impl RpcHelper {
 			KeyValue::new("to", format!("{:?}", to)),
 		];
 
-		let msg_size = rmp_to_vec_all_named(&msg)?.len() as u32;
+		//let msg_size = rmp_to_vec_all_named(&msg)?.len() as u32;
+		// some value to make things works while I figure out how to do better
+		let msg_size = 8192;
 		let permit = self
 			.0
 			.request_buffer_semaphore
@@ -151,6 +159,7 @@ impl RpcHelper {
 		self.0.metrics.rpc_counter.add(1, &metric_tags);
 
 		let node_id = to.into();
+
 		let rpc_call = endpoint
 			.call(&node_id, msg, strat.rs_priority)
 			.record_duration(&self.0.metrics.rpc_duration, &metric_tags);
@@ -187,7 +196,9 @@ impl RpcHelper {
 	) -> Vec<(Uuid, Result<S, Error>)>
 	where
 		M: Rpc<Response = Result<S, Error>>,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M>,
+		S: Send,
 	{
 		let msg = Arc::new(msg);
 		let resps = join_all(
@@ -209,7 +220,9 @@ impl RpcHelper {
 	) -> Vec<(Uuid, Result<S, Error>)>
 	where
 		M: Rpc<Response = Result<S, Error>>,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M>,
+		S: Send,
 	{
 		let to = self
 			.0
@@ -232,6 +245,7 @@ impl RpcHelper {
 	) -> Result<Vec<S>, Error>
 	where
 		M: Rpc<Response = Result<S, Error>> + 'static,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M> + 'static,
 		S: Send + 'static,
 	{
@@ -272,6 +286,7 @@ impl RpcHelper {
 	) -> Result<Vec<S>, Error>
 	where
 		M: Rpc<Response = Result<S, Error>> + 'static,
+		Result<S, Error>: SerializeMessage,
 		H: EndpointHandler<M> + 'static,
 		S: Send + 'static,
 	{

src/rpc/system.rs

@@ -71,6 +71,8 @@ impl Rpc for SystemRpc {
 	type Response = Result<SystemRpc, Error>;
 }
 
+impl AutoSerialize for SystemRpc {}
+
 /// This node's membership manager
 pub struct System {
 	/// The id of this node

src/table/gc.rs

@@ -39,7 +39,7 @@ pub(crate) struct TableGc<F: TableSchema + 'static, R: TableReplication + 'stati
 	endpoint: Arc<Endpoint<GcRpc, Self>>,
 }
 
-#[derive(Serialize, Deserialize)]
+#[derive(Serialize, Deserialize, Clone)]
 enum GcRpc {
 	Update(Vec<ByteBuf>),
 	DeleteIfEqualHash(Vec<(ByteBuf, Hash)>),
@@ -50,6 +50,8 @@ impl Rpc for GcRpc {
 	type Response = Result<GcRpc, Error>;
 }
 
+impl AutoSerialize for GcRpc {}
+
 impl<F, R> TableGc<F, R>
 where
 	F: TableSchema + 'static,

src/table/merkle.rs

@@ -52,7 +52,7 @@ pub struct MerkleNodeKey {
 	pub prefix: Vec<u8>,
 }
 
-#[derive(PartialEq, Eq, Debug, Serialize, Deserialize)]
+#[derive(PartialEq, Eq, Debug, Serialize, Deserialize, Clone)]
 pub enum MerkleNode {
 	// The empty Merkle node
 	Empty,

src/table/sync.rs

@@ -38,7 +38,7 @@ pub struct TableSyncer<F: TableSchema + 'static, R: TableReplication + 'static>
 	endpoint: Arc<Endpoint<SyncRpc, Self>>,
 }
 
-#[derive(Serialize, Deserialize)]
+#[derive(Serialize, Deserialize, Clone)]
 pub(crate) enum SyncRpc {
 	RootCkHash(Partition, Hash),
 	RootCkDifferent(bool),
@@ -52,6 +52,8 @@ impl Rpc for SyncRpc {
 	type Response = Result<SyncRpc, Error>;
 }
 
+impl AutoSerialize for SyncRpc {}
+
 struct SyncTodo {
 	todo: Vec<TodoPartition>,
 }

src/table/table.rs

@@ -58,10 +58,47 @@ pub(crate) enum TableRpc<F: TableSchema> {
 	Update(Vec<Arc<ByteBuf>>),
 }
 
+impl<F: TableSchema> Clone for TableRpc<F>
+where
+	F::P: Clone,
+	F::S: Clone,
+	F::Filter: Clone,
+{
+	fn clone(&self) -> Self {
+		use TableRpc::*;
+		match self {
+			Ok => Ok,
+			ReadEntry(f, s) => ReadEntry(f.clone(), s.clone()),
+			ReadEntryResponse(b) => ReadEntryResponse(b.clone()),
+			ReadRange {
+				partition,
+				begin_sort_key,
+				filter,
+				limit,
+				enumeration_order,
+			} => ReadRange {
+				partition: partition.clone(),
+				begin_sort_key: begin_sort_key.clone(),
+				filter: filter.clone(),
+				limit: *limit,
+				enumeration_order: enumeration_order.clone(),
+			},
+			Update(v) => Update(v.clone()),
+		}
+	}
+}
+
 impl<F: TableSchema> Rpc for TableRpc<F> {
 	type Response = Result<TableRpc<F>, Error>;
 }
 
+impl<F: TableSchema> AutoSerialize for TableRpc<F>
+where
+	F::P: Clone,
+	F::S: Clone,
+{
+}
+
 impl<F, R> Table<F, R>
 where
 	F: TableSchema + 'static,

src/util/Cargo.toml

@@ -14,6 +14,7 @@ path = "lib.rs"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+async-trait = "0.1.7"
 blake2 = "0.9"
 err-derive = "0.3"
 xxhash-rust = { version = "0.8", default-features = false, features = ["xxh3"] }

src/util/error.rs

@@ -4,7 +4,11 @@ use std::io;
 
 use err_derive::Error;
 
-use serde::{de::Visitor, Deserialize, Deserializer, Serialize, Serializer};
+use serde::de::Visitor;
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
+
+use netapp::endpoint::SerializeMessage;
+use netapp::util::AssociatedStream;
 
 use crate::data::*;
 
@@ -162,12 +166,26 @@ impl<T> OkOrMessage for Option<T> {
 // Upon deserialization, they all become a RemoteError with the
 // given representation.
 
+// can't use AutoSerialize because it requires Clone
+#[async_trait::async_trait]
+impl SerializeMessage for Error {
+	type SerializableSelf = String;
+	fn serialize_msg(&self) -> (Self::SerializableSelf, Option<AssociatedStream>) {
+		(self.to_string(), None)
+	}
+
+	async fn deserialize_msg(ser_self: Self::SerializableSelf, stream: AssociatedStream) -> Self {
+		// TODO verify no stream
+		Error::RemoteError(ser_self)
+	}
+}
+
 impl Serialize for Error {
 	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
 	where
 		S: Serializer,
 	{
-		serializer.serialize_str(&format!("{}", self))
+		serializer.serialize_str(&self.to_string())
 	}
 }