Try to send typed errors back and forth

TEMP

TEMP

First pass of structured errors

Improved error handling for channel joining failures

crates/client/src/client.rs

@@ -689,12 +689,7 @@ impl Client {
                 Ok(())
             }
             Err(error) => {
-                client.respond_with_error(
+                client.respond_with_error(receipt, error.to_proto())?;
-                    receipt,
-                    proto::Error {
-                        message: format!("{:?}", error),
-                    },
-                )?;
                 Err(error)
             }
         }

crates/collab/src/db/queries/channels.rs

@@ -1,5 +1,5 @@
 use super::*;
-use rpc::proto::channel_member::Kind;
+use rpc::{proto::channel_member::Kind, ErrorCode, ErrorCodeExt};
 use sea_orm::TryGetableMany;
 
 impl Database {
@@ -166,7 +166,7 @@ impl Database {
             }
 
             if role.is_none() || role == Some(ChannelRole::Banned) {
-                Err(anyhow!("not allowed"))?
+                Err(ErrorCode::Forbidden.anyhow())?
             }
             let role = role.unwrap();
 
@@ -1201,7 +1201,7 @@ impl Database {
         Ok(channel::Entity::find_by_id(channel_id)
             .one(&*tx)
             .await?
-            .ok_or_else(|| anyhow!("no such channel"))?)
+            .ok_or_else(|| proto::ErrorCode::NoSuchChannel.anyhow())?)
     }
 
     pub(crate) async fn get_or_create_channel_room(
@@ -1219,7 +1219,9 @@ impl Database {
         let room_id = if let Some(room) = room {
             if let Some(env) = room.environment {
                 if &env != environment {
-                    Err(anyhow!("must join using the {} release", env))?;
+                    Err(ErrorCode::WrongReleaseChannel
+                        .with_tag("required", &env)
+                        .anyhow())?;
                 }
             }
             room.id

crates/collab/src/rpc.rs

@@ -10,7 +10,7 @@ use crate::{
         User, UserId,
     },
     executor::Executor,
-    AppState, Result,
+    AppState, Error, Result,
 };
 use anyhow::anyhow;
 use async_tungstenite::tungstenite::{
@@ -44,7 +44,7 @@ use rpc::{
         self, Ack, AnyTypedEnvelope, EntityMessage, EnvelopedMessage, LiveKitConnectionInfo,
         RequestMessage, ShareProject, UpdateChannelBufferCollaborators,
     },
-    Connection, ConnectionId, Peer, Receipt, TypedEnvelope,
+    Connection, ConnectionId, ErrorCode, ErrorCodeExt, ErrorExt, Peer, Receipt, TypedEnvelope,
 };
 use serde::{Serialize, Serializer};
 use std::{
@@ -543,12 +543,11 @@ impl Server {
                         }
                     }
                     Err(error) => {
-                        peer.respond_with_error(
+                        let proto_err = match &error {
-                            receipt,
+                            Error::Internal(err) => err.to_proto(),
-                            proto::Error {
+                            _ => ErrorCode::Internal.message(format!("{}", error)).to_proto(),
-                                message: error.to_string(),
+                        };
-                            },
+                        peer.respond_with_error(receipt, proto_err)?;
-                        )?;
                         Err(error)
                     }
                 }

crates/rpc/proto/zed.proto

@@ -197,6 +197,18 @@ message Ack {}
 
 message Error {
     string message = 1;
+    ErrorCode code = 2;
+    repeated string tags = 3;
+}
+
+enum ErrorCode {
+    Internal = 0;
+    NoSuchChannel = 1;
+    Disconnected = 2;
+    SignedOut = 3;
+    UpgradeRequired = 4;
+    Forbidden = 5;
+    WrongReleaseChannel = 6;
 }
 
 message Test {

crates/rpc/src/error.rs

@@ -0,0 +1,223 @@
+/// Some helpers for structured error handling.
+///
+/// The helpers defined here allow you to pass type-safe error codes from
+/// the collab server to the client; and provide a mechanism for additional
+/// structured data alongside the message.
+///
+/// When returning an error, it can be as simple as:
+///
+/// `return Err(Error::Forbidden.into())`
+///
+/// If you'd like to log more context, you can set a message. These messages
+/// show up in our logs, but are not shown visibly to users.
+///
+/// `return Err(Error::Forbidden.message("not an admin").into())`
+///
+/// If you'd like to provide enough context that the UI can render a good error
+/// message (or would be helpful to see in a structured format in the logs), you
+/// can use .with_tag():
+///
+/// `return Err(Error::WrongReleaseChannel.with_tag("required", "stable").into())`
+///
+/// When handling an error you can use .error_code() to match which error it was
+/// and .error_tag() to read any tags.
+///
+/// ```
+/// match err.error_code() {
+///   ErrorCode::Forbidden => alert("I'm sorry I can't do that.")
+///   ErrorCode::WrongReleaseChannel =>
+///     alert(format!("You need to be on the {} release channel.", err.error_tag("required").unwrap()))
+///   ErrorCode::Internal => alert("Sorry, something went wrong")
+/// }
+/// ```
+///
+use crate::proto;
+pub use proto::ErrorCode;
+
+/// ErrorCodeExt provides some helpers for structured error handling.
+///
+/// The primary implementation is on the proto::ErrorCode to easily convert
+/// that into an anyhow::Error, which we use pervasively.
+///
+/// The RPCError struct provides support for further metadata if needed.
+pub trait ErrorCodeExt {
+    /// Return an anyhow::Error containing this.
+    /// (useful in places where .into() doesn't have enough type information)
+    fn anyhow(self) -> anyhow::Error;
+
+    /// Add a message to the error (by default the error code is used)
+    fn message(self, msg: String) -> RPCError;
+
+    /// Add a tag to the error. Tags are key value pairs that can be used
+    /// to send semi-structured data along with the error.
+    fn with_tag(self, k: &str, v: &str) -> RPCError;
+}
+
+impl ErrorCodeExt for proto::ErrorCode {
+    fn anyhow(self) -> anyhow::Error {
+        self.into()
+    }
+
+    fn message(self, msg: String) -> RPCError {
+        let err: RPCError = self.into();
+        err.message(msg)
+    }
+
+    fn with_tag(self, k: &str, v: &str) -> RPCError {
+        let err: RPCError = self.into();
+        err.with_tag(k, v)
+    }
+}
+
+/// ErrorExt provides helpers for structured error handling.
+///
+/// The primary implementation is on the anyhow::Error, which is
+/// what we use throughout our codebase. Though under the hood this
+pub trait ErrorExt {
+    /// error_code() returns the ErrorCode (or ErrorCode::Internal if there is none)
+    fn error_code(&self) -> proto::ErrorCode;
+    /// error_tag() returns the value of the tag with the given key, if any.
+    fn error_tag(&self, k: &str) -> Option<&str>;
+    /// to_proto() convers the error into a proto::Error
+    fn to_proto(&self) -> proto::Error;
+}
+
+impl ErrorExt for anyhow::Error {
+    fn error_code(&self) -> proto::ErrorCode {
+        if let Some(rpc_error) = self.downcast_ref::<RPCError>() {
+            rpc_error.code
+        } else {
+            proto::ErrorCode::Internal
+        }
+    }
+
+    fn error_tag(&self, k: &str) -> Option<&str> {
+        if let Some(rpc_error) = self.downcast_ref::<RPCError>() {
+            rpc_error.error_tag(k)
+        } else {
+            None
+        }
+    }
+
+    fn to_proto(&self) -> proto::Error {
+        if let Some(rpc_error) = self.downcast_ref::<RPCError>() {
+            rpc_error.to_proto()
+        } else {
+            ErrorCode::Internal.message(format!("{}", self)).to_proto()
+        }
+    }
+}
+
+impl From<proto::ErrorCode> for anyhow::Error {
+    fn from(value: proto::ErrorCode) -> Self {
+        RPCError {
+            request: None,
+            code: value,
+            msg: format!("{:?}", value).to_string(),
+            tags: Default::default(),
+        }
+        .into()
+    }
+}
+
+#[derive(Clone, Debug)]
+pub struct RPCError {
+    request: Option<String>,
+    msg: String,
+    code: proto::ErrorCode,
+    tags: Vec<String>,
+}
+
+/// RPCError is a structured error type that is returned by the collab server.
+/// In addition to a message, it lets you set a specific ErrorCode, and attach
+/// small amounts of metadata to help the client handle the error appropriately.
+///
+/// This struct is not typically used directly, as we pass anyhow::Error around
+/// in the app; however it is useful for chaining .message() and .with_tag() on
+/// ErrorCode.
+impl RPCError {
+    /// from_proto converts a proto::Error into an anyhow::Error containing
+    /// an RPCError.
+    pub fn from_proto(error: &proto::Error, request: &str) -> anyhow::Error {
+        RPCError {
+            request: Some(request.to_string()),
+            code: error.code(),
+            msg: error.message.clone(),
+            tags: error.tags.clone(),
+        }
+        .into()
+    }
+}
+
+impl ErrorCodeExt for RPCError {
+    fn message(mut self, msg: String) -> RPCError {
+        self.msg = msg;
+        self
+    }
+
+    fn with_tag(mut self, k: &str, v: &str) -> RPCError {
+        self.tags.push(format!("{}={}", k, v));
+        self
+    }
+
+    fn anyhow(self) -> anyhow::Error {
+        self.into()
+    }
+}
+
+impl ErrorExt for RPCError {
+    fn error_tag(&self, k: &str) -> Option<&str> {
+        for tag in &self.tags {
+            let mut parts = tag.split('=');
+            if let Some(key) = parts.next() {
+                if key == k {
+                    return parts.next();
+                }
+            }
+        }
+        None
+    }
+
+    fn error_code(&self) -> proto::ErrorCode {
+        self.code
+    }
+
+    fn to_proto(&self) -> proto::Error {
+        proto::Error {
+            code: self.code as i32,
+            message: self.msg.clone(),
+            tags: self.tags.clone(),
+        }
+    }
+}
+
+impl std::error::Error for RPCError {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        None
+    }
+}
+
+impl std::fmt::Display for RPCError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        if let Some(request) = &self.request {
+            write!(f, "RPC request {} failed: {}", request, self.msg)?
+        } else {
+            write!(f, "{}", self.msg)?
+        }
+        for tag in &self.tags {
+            write!(f, " {}", tag)?
+        }
+        Ok(())
+    }
+}
+
+impl From<proto::ErrorCode> for RPCError {
+    fn from(code: proto::ErrorCode) -> Self {
+        RPCError {
+            request: None,
+            code,
+            msg: format!("{:?}", code).to_string(),
+            tags: Default::default(),
+        }
+    }
+}

crates/rpc/src/peer.rs

@@ -1,3 +1,5 @@
+use crate::{ErrorCode, ErrorCodeExt, ErrorExt, RPCError};
+
 use super::{
     proto::{self, AnyTypedEnvelope, EnvelopedMessage, MessageStream, PeerId, RequestMessage},
     Connection,
@@ -423,11 +425,7 @@ impl Peer {
             let (response, _barrier) = rx.await.map_err(|_| anyhow!("connection was closed"))?;
 
             if let Some(proto::envelope::Payload::Error(error)) = &response.payload {
-                Err(anyhow!(
+                Err(RPCError::from_proto(&error, T::NAME))
-                    "RPC request {} failed - {}",
-                    T::NAME,
-                    error.message
-                ))
             } else {
                 Ok(TypedEnvelope {
                     message_id: response.id,
@@ -516,9 +514,12 @@ impl Peer {
         envelope: Box<dyn AnyTypedEnvelope>,
     ) -> Result<()> {
         let connection = self.connection_state(envelope.sender_id())?;
-        let response = proto::Error {
+        let response = ErrorCode::Internal
-            message: format!("message {} was not handled", envelope.payload_type_name()),
+            .message(format!(
-        };
+                "message {} was not handled",
+                envelope.payload_type_name()
+            ))
+            .to_proto();
         let message_id = connection
             .next_message_id
             .fetch_add(1, atomic::Ordering::SeqCst);
@@ -692,17 +693,17 @@ mod tests {
                 server
                     .send(
                         server_to_client_conn_id,
-                        proto::Error {
+                        ErrorCode::Internal
-                            message: "message 1".to_string(),
+                            .message("message 1".to_string())
-                        },
+                            .to_proto(),
                     )
                     .unwrap();
                 server
                     .send(
                         server_to_client_conn_id,
-                        proto::Error {
+                        ErrorCode::Internal
-                            message: "message 2".to_string(),
+                            .message("message 2".to_string())
-                        },
+                            .to_proto(),
                     )
                     .unwrap();
                 server.respond(request.receipt(), proto::Ack {}).unwrap();
@@ -797,17 +798,17 @@ mod tests {
                 server
                     .send(
                         server_to_client_conn_id,
-                        proto::Error {
+                        ErrorCode::Internal
-                            message: "message 1".to_string(),
+                            .message("message 1".to_string())
-                        },
+                            .to_proto(),
                     )
                     .unwrap();
                 server
                     .send(
                         server_to_client_conn_id,
-                        proto::Error {
+                        ErrorCode::Internal
-                            message: "message 2".to_string(),
+                            .message("message 2".to_string())
-                        },
+                            .to_proto(),
                     )
                     .unwrap();
                 server.respond(request1.receipt(), proto::Ack {}).unwrap();

crates/rpc/src/rpc.rs

@@ -1,10 +1,12 @@
 pub mod auth;
 mod conn;
+mod error;
 mod notification;
 mod peer;
 pub mod proto;
 
 pub use conn::Connection;
+pub use error::*;
 pub use notification::*;
 pub use peer::*;
 mod macros;

crates/workspace/src/workspace.rs

@@ -14,8 +14,8 @@ mod workspace_settings;
 use anyhow::{anyhow, Context as _, Result};
 use call::ActiveCall;
 use client::{
-    proto::{self, PeerId},
+    proto::{self, ErrorCode, PeerId},
-    Client, Status, TypedEnvelope, UserStore,
+    Client, ErrorExt, Status, TypedEnvelope, UserStore,
 };
 use collections::{hash_map, HashMap, HashSet};
 use dock::{Dock, DockPosition, Panel, PanelButtons, PanelHandle};
@@ -3919,10 +3919,10 @@ async fn join_channel_internal(
             | Status::Reconnecting
             | Status::Reauthenticating => continue,
             Status::Connected { .. } => break 'outer,
-            Status::SignedOut => return Err(anyhow!("not signed in")),
+            Status::SignedOut => return Err(ErrorCode::SignedOut.into()),
-            Status::UpgradeRequired => return Err(anyhow!("zed is out of date")),
+            Status::UpgradeRequired => return Err(ErrorCode::UpgradeRequired.into()),
             Status::ConnectionError | Status::ConnectionLost | Status::ReconnectionError { .. } => {
-                return Err(anyhow!("zed is offline"))
+                return Err(ErrorCode::Disconnected.into())
             }
         }
     }
@@ -3995,9 +3995,23 @@ pub fn join_channel(
             if let Some(active_window) = active_window {
                 active_window
                     .update(&mut cx, |_, cx| {
+                        let message:SharedString = match err.error_code() {
+                            ErrorCode::SignedOut => {
+                                "Failed to join channel\n\nPlease sign in to continue.".into()
+                            },
+                            ErrorCode::UpgradeRequired => {
+                                "Failed to join channel\n\nPlease update to the latest version of Zed to continue.".into()
+                            },
+                            ErrorCode::NoSuchChannel => {
+                                "Failed to find channel\n\nPlease check the link and try again.".into()
+                            },
+                            ErrorCode::Disconnected => "Failed to join channel\n\nPlease check your internet connection and try again.".into(),
+                            ErrorCode::WrongReleaseChannel => format!("Failed to join channel\n\nOther people in the channel are using the {} release of Zed, please switch to that release instead.", err.error_tag("required").unwrap_or("other")).into(),
+                            _ => format!("Failed to join channel\n\n{}\n\nPlease try again.", err).into(),
+                        };
                         cx.prompt(
                             PromptLevel::Critical,
-                            &format!("Failed to join channel: {}", err),
+                            &message,
                             &["Ok"],
                         )
                     })?