Rework memdx error model

Motivation
----------
The memdx error model does not currently satisfy what we need from
it. We need to be able to attach cluster configs and error context
to errors sometimes.

Changes
--------
Rework memdx error model to include more types of error and the
top level error be a struct.

sdk/couchbase-core/src/cbconfig/mod.rs

@@ -2,7 +2,7 @@ use std::collections::HashMap;
 
 use serde::Deserialize;
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct VBucketServerMap {
     #[serde(alias = "hashAlgorithm")]
     pub hash_algorithm: String,
@@ -14,13 +14,13 @@ pub struct VBucketServerMap {
     pub vbucket_map: Vec<Vec<i16>>,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct ConfigDDocs {
     #[serde(alias = "uri")]
     pub uri: String,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, Clone)]
 pub struct TerseExtNodePorts {
     #[serde(alias = "kv")]
     pub kv: Option<i64>,
@@ -61,23 +61,23 @@ pub struct TerseExtNodePorts {
     pub backup_ssl: Option<i64>,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct TerseExtNodeAltAddresses {
     #[serde(alias = "ports")]
     pub ports: TerseExtNodePorts,
     #[serde(alias = "hostname")]
     pub hostname: String,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct TerseNodePorts {
     #[serde(alias = "direct")]
     pub direct: Option<u16>,
     #[serde(alias = "proxy")]
     pub proxy: Option<u16>,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct TerseNodeConfig {
     #[serde(alias = "couchbaseApiBase")]
     pub couchbase_api_base: Option<String>,
@@ -87,7 +87,7 @@ pub struct TerseNodeConfig {
     pub ports: Option<TerseNodePorts>,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct TerseNodeExtConfig {
     #[serde(alias = "services")]
     pub services: Option<TerseExtNodePorts>,
@@ -99,7 +99,7 @@ pub struct TerseNodeExtConfig {
     pub alternate_addresses: HashMap<String, TerseExtNodeAltAddresses>,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Debug, Clone)]
 pub struct TerseConfig {
     #[serde(alias = "rev")]
     pub rev: i64,

sdk/couchbase-core/src/error.rs

@@ -1,22 +1,22 @@
 use std::fmt::Display;
 
 use crate::error::CoreError::{Dispatch, Placeholder, PlaceholderMemdxWrapper};
-use crate::memdx::error::MemdxError;
+use crate::memdx::error::{Error, ErrorKind};
 
-#[derive(thiserror::Error, Debug, Eq, PartialEq)]
+#[derive(thiserror::Error, Debug)]
 pub enum CoreError {
     #[error("Dispatch error {0}")]
-    Dispatch(MemdxError),
+    Dispatch(Error),
     #[error("Placeholder error {0}")]
     Placeholder(String),
     #[error("Placeholder memdx wrapper error {0}")]
-    PlaceholderMemdxWrapper(MemdxError),
+    PlaceholderMemdxWrapper(Error),
 }
 
-impl From<MemdxError> for CoreError {
-    fn from(value: MemdxError) -> Self {
-        match value {
-            MemdxError::Dispatch(_) => Dispatch(value),
+impl From<Error> for CoreError {
+    fn from(value: Error) -> Self {
+        match value.kind.as_ref() {
+            ErrorKind::Dispatch(_) => Dispatch(value),
             _ => PlaceholderMemdxWrapper(value),
         }
     }

sdk/couchbase-core/src/kvclient.rs

@@ -176,7 +176,7 @@ where
         }
 
         let (connection_close_tx, mut connection_close_rx) =
-            oneshot::channel::<crate::memdx::client::MemdxResult<()>>();
+            oneshot::channel::<crate::memdx::error::Result<()>>();
         let memdx_client_opts = DispatcherOptions {
             on_connection_close_handler: Some(connection_close_tx),
             orphan_handler: opts.orphan_handler,

sdk/couchbase-core/src/memdx/auth_mechanism.rs

@@ -1,4 +1,4 @@
-use crate::memdx::error::MemdxError;
+use crate::memdx::error::{Error, ErrorKind};
 
 #[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
 pub enum AuthMechanism {
@@ -22,7 +22,7 @@ impl From<AuthMechanism> for Vec<u8> {
 }
 
 impl TryFrom<&str> for AuthMechanism {
-    type Error = MemdxError;
+    type Error = Error;
 
     fn try_from(value: &str) -> Result<Self, Self::Error> {
         let mech = match value {
@@ -31,10 +31,10 @@ impl TryFrom<&str> for AuthMechanism {
             "SCRAM-SHA256" => AuthMechanism::ScramSha256,
             "SCRAM-SHA512" => AuthMechanism::ScramSha512,
             _ => {
-                return Err(MemdxError::Protocol(format!(
-                    "Unknown auth mechanism {}",
-                    value
-                )));
+                return Err(ErrorKind::Protocol {
+                    msg: format!("Unknown auth mechanism {}", value),
+                }
+                .into());
             }
         };
 

sdk/couchbase-core/src/memdx/client.rs

@@ -26,12 +26,12 @@ use crate::memdx::client_response::ClientResponse;
 use crate::memdx::codec::KeyValueCodec;
 use crate::memdx::connection::{Connection, ConnectionType};
 use crate::memdx::dispatcher::{Dispatcher, DispatcherOptions};
-use crate::memdx::error::{CancellationErrorKind, MemdxError};
+use crate::memdx::error;
+use crate::memdx::error::{CancellationErrorKind, Error, ErrorKind};
 use crate::memdx::packet::{RequestPacket, ResponsePacket};
 use crate::memdx::pendingop::ClientPendingOp;
 
-pub type MemdxResult<T> = std::result::Result<T, MemdxError>;
-type ResponseSender = Sender<MemdxResult<ClientResponse>>;
+type ResponseSender = Sender<error::Result<ClientResponse>>;
 type OpaqueMap = HashMap<u32, Arc<ResponseSender>>;
 pub(crate) type CancellationSender = UnboundedSender<(u32, CancellationErrorKind)>;
 
@@ -41,7 +41,7 @@ struct ReadLoopOptions {
     pub local_addr: Option<SocketAddr>,
     pub peer_addr: Option<SocketAddr>,
     pub orphan_handler: Arc<UnboundedSender<ResponsePacket>>,
-    pub on_connection_close_tx: Option<oneshot::Sender<MemdxResult<()>>>,
+    pub on_connection_close_tx: Option<oneshot::Sender<error::Result<()>>>,
     pub on_client_close_rx: Receiver<()>,
 }
 
@@ -90,7 +90,10 @@ impl Client {
         for entry in opaque_map.iter() {
             entry
                 .1
-                .send(Err(MemdxError::ClosedInFlight))
+                .send(Err(ErrorKind::Cancelled(
+                    CancellationErrorKind::ClosedInFlight,
+                )
+                .into()))
                 .await
                 .unwrap_or_default();
         }
@@ -100,7 +103,7 @@ impl Client {
         stream: FramedRead<ReadHalf<TcpStream>, KeyValueCodec>,
         op_cancel_rx: UnboundedReceiver<(u32, CancellationErrorKind)>,
         opaque_map: MutexGuard<'_, OpaqueMap>,
-        on_connection_close_tx: Option<oneshot::Sender<MemdxResult<()>>>,
+        on_connection_close_tx: Option<oneshot::Sender<error::Result<()>>>,
     ) {
         drop(stream);
         drop(op_cancel_rx);
@@ -138,7 +141,7 @@ impl Client {
                                 drop(map);
 
                                 sender
-                                    .send(Err(MemdxError::Cancelled(cancel_info.1)))
+                                    .send(Err(ErrorKind::Cancelled(cancel_info.1).into()))
                                     .await
                                     .unwrap();
                             } else {
@@ -300,7 +303,7 @@ impl Dispatcher for Client {
         }
     }
 
-    async fn dispatch(&self, mut packet: RequestPacket) -> MemdxResult<ClientPendingOp> {
+    async fn dispatch(&self, mut packet: RequestPacket) -> error::Result<ClientPendingOp> {
         let (response_tx, response_rx) = mpsc::channel(1);
         let opaque = self.register_handler(Arc::new(response_tx)).await;
         packet.opaque = Some(opaque);
@@ -323,14 +326,14 @@ impl Dispatcher for Client {
                 let mut map = requests.lock().await;
                 map.remove(&opaque);
 
-                Err(MemdxError::Dispatch(e.kind()))
+                Err(ErrorKind::Dispatch(Arc::new(e)).into())
             }
         }
     }
 
-    async fn close(&self) -> MemdxResult<()> {
+    async fn close(&self) -> error::Result<()> {
         if self.closed.swap(true, Ordering::SeqCst) {
-            return Err(MemdxError::Closed);
+            return Err(ErrorKind::Closed.into());
         }
 
         let mut close_err = None;
@@ -354,7 +357,7 @@ impl Dispatcher for Client {
         Self::drain_opaque_map(map).await;
 
         if let Some(e) = close_err {
-            return Err(MemdxError::from(e));
+            return Err(ErrorKind::Io(Arc::new(e)).into());
         }
 
         Ok(())
@@ -405,7 +408,7 @@ mod tests {
         .expect("Could not connect");
 
         let (orphan_tx, mut orphan_rx) = unbounded_channel::<ResponsePacket>();
-        let (close_tx, mut close_rx) = oneshot::channel::<crate::memdx::client::MemdxResult<()>>();
+        let (close_tx, mut close_rx) = oneshot::channel::<crate::memdx::error::Result<()>>();
 
         tokio::spawn(async move {
             loop {

sdk/couchbase-core/src/memdx/codec.rs

@@ -3,8 +3,7 @@ use std::io;
 use tokio_util::bytes::{Buf, BufMut, BytesMut};
 use tokio_util::codec::{Decoder, Encoder};
 
-use crate::memdx::error::MemdxError;
-use crate::memdx::error::MemdxError::Protocol;
+use crate::memdx::error::{Error, ErrorKind};
 use crate::memdx::magic::Magic;
 use crate::memdx::opcode::OpCode;
 use crate::memdx::packet::{RequestPacket, ResponsePacket};
@@ -17,7 +16,7 @@ pub struct KeyValueCodec(());
 
 impl Decoder for KeyValueCodec {
     type Item = ResponsePacket;
-    type Error = MemdxError;
+    type Error = Error;
 
     fn decode(&mut self, buf: &mut BytesMut) -> Result<Option<Self::Item>, Self::Error> {
         let buf_len = buf.len();
@@ -28,7 +27,11 @@ impl Decoder for KeyValueCodec {
 
         let total_body_len = match buf[8..12].try_into() {
             Ok(v) => u32::from_be_bytes(v),
-            Err(e) => return Err(Protocol(e.to_string())),
+            Err(e) => {
+                return Err(Error {
+                    kind: ErrorKind::Protocol { msg: e.to_string() }.into(),
+                })
+            }
         } as usize;
 
         if buf_len < (HEADER_SIZE + total_body_len) {

sdk/couchbase-core/src/memdx/connection.rs

@@ -12,8 +12,8 @@ use tokio_rustls::rustls::client::danger::{
 use tokio_rustls::rustls::pki_types::{CertificateDer, IpAddr, ServerName, UnixTime};
 use tokio_rustls::TlsConnector;
 
-use crate::memdx::client::MemdxResult;
-use crate::memdx::error::MemdxError;
+use crate::memdx::error::ErrorKind;
+use crate::memdx::error::Result;
 
 #[derive(Debug, Default)]
 pub struct TlsConfig {
@@ -42,7 +42,7 @@ pub struct Connection {
 }
 
 impl Connection {
-    pub async fn connect(addr: SocketAddr, opts: ConnectOptions) -> MemdxResult<Connection> {
+    pub async fn connect(addr: SocketAddr, opts: ConnectOptions) -> Result<Connection> {
         let remote_addr = addr.to_string();
 
         if let Some(tls_config) = opts.tls_config {
@@ -55,19 +55,19 @@ impl Connection {
             } else if let Some(roots) = tls_config.root_certs {
                 builder.with_root_certificates(roots).with_no_client_auth()
             } else {
-                return Err(MemdxError::Generic(
-                    "If tls config is specified then roots or accept_all_certs must be specified"
+                return Err(ErrorKind::InvalidArgument {
+                    msg: "If tls config is specified then roots or accept_all_certs must be specified"
                         .to_string(),
-                ));
+                }.into());
             };
 
             let tcp_socket = timeout_at(opts.deadline, TcpStream::connect(remote_addr))
                 .await?
-                .map_err(|e| MemdxError::Connect(e.kind()))?;
+                .map_err(|e| ErrorKind::Connect(Arc::new(e)))?;
 
             tcp_socket
                 .set_nodelay(false)
-                .map_err(|e| MemdxError::Connect(e.kind()))?;
+                .map_err(|e| ErrorKind::Connect(Arc::new(e)))?;
 
             let local_addr = match tcp_socket.local_addr() {
                 Ok(addr) => Some(addr),
@@ -84,7 +84,7 @@ impl Connection {
                 connector.connect(ServerName::IpAddress(IpAddr::from(addr.ip())), tcp_socket),
             )
             .await?
-            .map_err(|e| MemdxError::Connect(e.kind()))?;
+            .map_err(|e| ErrorKind::Connect(Arc::new(e)))?;
 
             Ok(Connection {
                 inner: ConnectionType::Tls(socket),
@@ -94,10 +94,10 @@ impl Connection {
         } else {
             let socket = timeout_at(opts.deadline, TcpStream::connect(remote_addr))
                 .await?
-                .map_err(|e| MemdxError::Connect(e.kind()))?;
+                .map_err(|e| ErrorKind::Connect(Arc::new(e)))?;
             socket
                 .set_nodelay(false)
-                .map_err(|e| MemdxError::Connect(e.kind()))?;
+                .map_err(|e| ErrorKind::Connect(Arc::new(e)))?;
 
             let local_addr = match socket.local_addr() {
                 Ok(addr) => Some(addr),

sdk/couchbase-core/src/memdx/dispatcher.rs

@@ -4,20 +4,20 @@ use async_trait::async_trait;
 use tokio::sync::mpsc::UnboundedSender;
 use tokio::sync::oneshot;
 
-use crate::memdx::client::MemdxResult;
 use crate::memdx::connection::Connection;
+use crate::memdx::error::Result;
 use crate::memdx::packet::{RequestPacket, ResponsePacket};
 use crate::memdx::pendingop::ClientPendingOp;
 
 #[derive(Debug)]
 pub struct DispatcherOptions {
     pub orphan_handler: Arc<UnboundedSender<ResponsePacket>>,
-    pub on_connection_close_handler: Option<oneshot::Sender<MemdxResult<()>>>,
+    pub on_connection_close_handler: Option<oneshot::Sender<Result<()>>>,
 }
 
 #[async_trait]
 pub trait Dispatcher: Send + Sync {
     fn new(conn: Connection, opts: DispatcherOptions) -> Self;
-    async fn dispatch(&self, packet: RequestPacket) -> MemdxResult<ClientPendingOp>;
-    async fn close(&self) -> MemdxResult<()>;
+    async fn dispatch(&self, packet: RequestPacket) -> Result<ClientPendingOp>;
+    async fn close(&self) -> Result<()>;
 }