Add OrderTag to Req and Resp, refactor errors

1 files changed, 102 insertions, 65 deletions

diff --git a/src/message.rs b/src/message.rs
index 61d01d0..ca68cac 100644
--- a/src/message.rs
+++ b/src/message.rs
@@ -3,6 +3,7 @@ use std::marker::PhantomData;
 use std::sync::Arc;
 
 use bytes::{BufMut, Bytes, BytesMut};
+use rand::prelude::*;
 use serde::{Deserialize, Serialize};
 
 use futures::stream::StreamExt;
@@ -40,6 +41,24 @@ pub const PRIO_SECONDARY: RequestPriority = 0x01;
 
 // ----
 
+#[derive(Clone, Copy)]
+pub struct OrderTagStream(u64);
+#[derive(Clone, Copy, Serialize, Deserialize, Debug)]
+pub struct OrderTag(u64, u64);
+
+impl OrderTag {
+	pub fn stream() -> OrderTagStream {
+		OrderTagStream(thread_rng().gen())
+	}
+}
+impl OrderTagStream {
+	pub fn order(&self, order: u64) -> OrderTag {
+		OrderTag(self.0, order)
+	}
+}
+
+// ----
+
 /// This trait should be implemented by all messages your application
 /// wants to handle
 pub trait Message: Serialize + for<'de> Deserialize<'de> + Send + Sync + 'static {
@@ -56,6 +75,7 @@ pub struct Req<M: Message> {
 	pub(crate) msg: Arc<M>,
 	pub(crate) msg_ser: Option<Bytes>,
 	pub(crate) stream: AttachedStream,
+	pub(crate) order_tag: Option<OrderTag>,
 }
 
 impl<M: Message> Req<M> {
@@ -77,6 +97,13 @@ impl<M: Message> Req<M> {
 		}
 	}
 
+	pub fn with_order_tag(self, order_tag: OrderTag) -> Self {
+		Self {
+			order_tag: Some(order_tag),
+			..self
+		}
+	}
+
 	pub fn msg(&self) -> &M {
 		&self.msg
 	}
@@ -97,6 +124,7 @@ impl<M: Message> Req<M> {
 			telemetry_id,
 			msg: self.msg_ser.unwrap(),
 			stream: self.stream.into_stream(),
+			order_tag: self.order_tag,
 		}
 	}
 
@@ -109,6 +137,7 @@ impl<M: Message> Req<M> {
 				.stream
 				.map(AttachedStream::Stream)
 				.unwrap_or(AttachedStream::None),
+			order_tag: enc.order_tag,
 		})
 	}
 }
@@ -125,6 +154,7 @@ impl<M: Message> IntoReq<M> for M {
 			msg: Arc::new(self),
 			msg_ser: Some(Bytes::from(msg_ser)),
 			stream: AttachedStream::None,
+			order_tag: None,
 		})
 	}
 	fn into_req_local(self) -> Req<M> {
@@ -132,6 +162,7 @@ impl<M: Message> IntoReq<M> for M {
 			msg: Arc::new(self),
 			msg_ser: None,
 			stream: AttachedStream::None,
+			order_tag: None,
 		}
 	}
 }
@@ -158,6 +189,7 @@ impl<M: Message> Clone for Req<M> {
 			msg: self.msg.clone(),
 			msg_ser: self.msg_ser.clone(),
 			stream,
+			order_tag: self.order_tag,
 		}
 	}
 }
@@ -184,6 +216,7 @@ pub struct Resp<M: Message> {
 	pub(crate) _phantom: PhantomData<M>,
 	pub(crate) msg: M::Response,
 	pub(crate) stream: AttachedStream,
+	pub(crate) order_tag: Option<OrderTag>,
 }
 
 impl<M: Message> Resp<M> {
@@ -192,6 +225,7 @@ impl<M: Message> Resp<M> {
 			_phantom: Default::default(),
 			msg: v,
 			stream: AttachedStream::None,
+			order_tag: None,
 		}
 	}
 
@@ -209,6 +243,13 @@ impl<M: Message> Resp<M> {
 		}
 	}
 
+	pub fn with_order_tag(self, order_tag: OrderTag) -> Self {
+		Self {
+			order_tag: Some(order_tag),
+			..self
+		}
+	}
+
 	pub fn msg(&self) -> &M::Response {
 		&self.msg
 	}
@@ -222,26 +263,24 @@ impl<M: Message> Resp<M> {
 	}
 
 	pub(crate) fn into_enc(self) -> Result<RespEnc, rmp_serde::encode::Error> {
-		Ok(RespEnc::Success {
+		Ok(RespEnc {
 			msg: rmp_to_vec_all_named(&self.msg)?.into(),
 			stream: self.stream.into_stream(),
+			order_tag: self.order_tag,
 		})
 	}
 
 	pub(crate) fn from_enc(enc: RespEnc) -> Result<Self, Error> {
-		match enc {
-			RespEnc::Success { msg, stream } => {
-				let msg = rmp_serde::decode::from_read_ref(&msg)?;
-				Ok(Self {
-					_phantom: Default::default(),
-					msg,
-					stream: stream
-						.map(AttachedStream::Stream)
-						.unwrap_or(AttachedStream::None),
-				})
-			}
-			RespEnc::Error { code, message } => Err(Error::Remote(code, message)),
-		}
+		let msg = rmp_serde::decode::from_read_ref(&enc.msg)?;
+		Ok(Self {
+			_phantom: Default::default(),
+			msg,
+			stream: enc
+				.stream
+				.map(AttachedStream::Stream)
+				.unwrap_or(AttachedStream::None),
+			order_tag: enc.order_tag,
+		})
 	}
 }
 
@@ -295,10 +334,11 @@ pub(crate) struct ReqEnc {
 	pub(crate) telemetry_id: Bytes,
 	pub(crate) msg: Bytes,
 	pub(crate) stream: Option<ByteStream>,
+	pub(crate) order_tag: Option<OrderTag>,
 }
 
 impl ReqEnc {
-	pub(crate) fn encode(self) -> ByteStream {
+	pub(crate) fn encode(self) -> (ByteStream, Option<OrderTag>) {
 		let mut buf = BytesMut::with_capacity(
 			self.path.len() + self.telemetry_id.len() + self.msg.len() + 16,
 		);
@@ -315,15 +355,18 @@ impl ReqEnc {
 
 		let header = buf.freeze();
 
-		if let Some(stream) = self.stream {
+		let res_stream: ByteStream = if let Some(stream) = self.stream {
 			Box::pin(futures::stream::iter([Ok(header), Ok(self.msg)]).chain(stream))
 		} else {
 			Box::pin(futures::stream::iter([Ok(header), Ok(self.msg)]))
-		}
+		};
+		(res_stream, self.order_tag)
 	}
 
 	pub(crate) async fn decode(stream: ByteStream) -> Result<Self, Error> {
-		Self::decode_aux(stream).await.map_err(|_| Error::Framing)
+		Self::decode_aux(stream)
+			.await
+			.map_err(read_exact_error_to_error)
 	}
 
 	async fn decode_aux(stream: ByteStream) -> Result<Self, ReadExactError> {
@@ -346,6 +389,7 @@ impl ReqEnc {
 			telemetry_id,
 			msg,
 			stream: Some(reader.into_stream()),
+			order_tag: None,
 		})
 	}
 }
@@ -360,74 +404,67 @@ impl ReqEnc {
 /// - message length + 1: u8
 /// - error code: u8
 /// - message: [u8; message_length]
-pub(crate) enum RespEnc {
-	Error {
-		code: u8,
-		message: String,
-	},
-	Success {
-		msg: Bytes,
-		stream: Option<ByteStream>,
-	},
+pub(crate) struct RespEnc {
+	msg: Bytes,
+	stream: Option<ByteStream>,
+	order_tag: Option<OrderTag>,
 }
 
 impl RespEnc {
-	pub(crate) fn from_err(e: Error) -> Self {
-		RespEnc::Error {
-			code: e.code(),
-			message: format!("{}", e),
-		}
-	}
-
-	pub(crate) fn encode(self) -> ByteStream {
-		match self {
-			RespEnc::Success { msg, stream } => {
-				let mut buf = BytesMut::with_capacity(msg.len() + 8);
-
-				buf.put_u8(0);
+	pub(crate) fn encode(resp: Result<Self, Error>) -> (ByteStream, Option<OrderTag>) {
+		match resp {
+			Ok(Self {
+				msg,
+				stream,
+				order_tag,
+			}) => {
+				let mut buf = BytesMut::with_capacity(4);
 				buf.put_u32(msg.len() as u32);
-
 				let header = buf.freeze();
 
-				if let Some(stream) = stream {
+				let res_stream: ByteStream = if let Some(stream) = stream {
 					Box::pin(futures::stream::iter([Ok(header), Ok(msg)]).chain(stream))
 				} else {
 					Box::pin(futures::stream::iter([Ok(header), Ok(msg)]))
-				}
+				};
+				(res_stream, order_tag)
 			}
-			RespEnc::Error { code, message } => {
-				let mut buf = BytesMut::with_capacity(message.len() + 8);
-				buf.put_u8(1 + message.len() as u8);
-				buf.put_u8(code);
-				buf.put(message.as_bytes());
-				let header = buf.freeze();
-				Box::pin(futures::stream::once(async move { Ok(header) }))
+			Err(err) => {
+				let err = std::io::Error::new(
+					std::io::ErrorKind::Other,
+					format!("netapp error: {}", err),
+				);
+				(
+					Box::pin(futures::stream::once(async move { Err(err) })),
+					None,
+				)
 			}
 		}
 	}
 
 	pub(crate) async fn decode(stream: ByteStream) -> Result<Self, Error> {
-		Self::decode_aux(stream).await.map_err(|_| Error::Framing)
+		Self::decode_aux(stream)
+			.await
+			.map_err(read_exact_error_to_error)
 	}
 
 	async fn decode_aux(stream: ByteStream) -> Result<Self, ReadExactError> {
 		let mut reader = ByteStreamReader::new(stream);
 
-		let is_err = reader.read_u8().await?;
+		let msg_len = reader.read_u32().await?;
+		let msg = reader.read_exact(msg_len as usize).await?;
 
-		if is_err > 0 {
-			let code = reader.read_u8().await?;
-			let message = reader.read_exact(is_err as usize - 1).await?;
-			let message = String::from_utf8(message.to_vec()).unwrap_or_default();
-			Ok(RespEnc::Error { code, message })
-		} else {
-			let msg_len = reader.read_u32().await?;
-			let msg = reader.read_exact(msg_len as usize).await?;
+		Ok(Self {
+			msg,
+			stream: Some(reader.into_stream()),
+			order_tag: None,
+		})
+	}
+}
 
-			Ok(RespEnc::Success {
-				msg,
-				stream: Some(reader.into_stream()),
-			})
-		}
+fn read_exact_error_to_error(e: ReadExactError) -> Error {
+	match e {
+		ReadExactError::Stream(err) => Error::Remote(err.kind(), err.to_string()),
+		ReadExactError::UnexpectedEos => Error::Framing,
 	}
 }