Merge pull request #190 from posit-dev/feature/frontend-comm-spec

Switch to new frontend comm spec

crates/amalthea/src/comm/base_comm.rs

@@ -39,3 +39,16 @@ pub fn json_rpc_error(code: JsonRpcErrorCode, message: String) -> Value {
         }
     })
 }
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub struct JsonRpcError {
+    pub error: JsonRpcErrorData,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub struct JsonRpcErrorData {
+    pub message: String,
+    pub code: JsonRpcErrorCode,
+}

crates/amalthea/src/comm/comm_channel.rs

@@ -36,7 +36,7 @@ pub enum Comm {
     Other(String),
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Clone, Debug, PartialEq)]
 pub enum CommMsg {
     /// A message that is part of a Remote Procedure Call (RPC). The first value
     /// is the unique ID of the RPC invocation (i.e. the Jupyter message ID),

crates/amalthea/src/comm/comm_manager.rs

@@ -152,16 +152,15 @@ impl CommManager {
 
                     // If we found it, send the message to the comm. TODO: Fewer unwraps
                     if let Some(index) = index {
-                        self.open_comms
-                            .get(index)
-                            .unwrap()
-                            .incoming_tx
-                            .send(msg)
-                            .unwrap();
+                        let comm = self.open_comms.get(index).unwrap();
+                        log::trace!("Comm manager: Sending message to comm '{}'", comm.comm_name);
+
+                        comm.incoming_tx.send(msg).unwrap();
                     } else {
-                        warn!(
+                        log::warn!(
                             "Received message for unknown comm channel {}: {:?}",
-                            comm_id, msg
+                            comm_id,
+                            msg
                         );
                     }
                 },

crates/amalthea/src/comm/frontend_comm.rs

@@ -1,50 +1,105 @@
-/*
- * frontend_comm.rs
- *
- * Copyright (C) 2023 Posit Software, PBC. All rights reserved.
- *
- */
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (C) 2023 Posit Software, PBC. All rights reserved.
+ *--------------------------------------------------------------------------------------------*/
+
+//
+// AUTO-GENERATED from frontend.json; do not edit.
+//
 
 use serde::Deserialize;
 use serde::Serialize;
-use serde_json::Value;
 
-use crate::comm::base_comm::JsonRpcErrorCode;
-use crate::wire::client_event::ClientEvent;
+/// Items in Params
+pub type Params = serde_json::Value;
+
+/// The method result
+pub type CallMethodResult = serde_json::Value;
 
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(tag = "msg_type", rename_all = "snake_case")]
-pub enum FrontendMessage {
-    Event(ClientEvent),
-    RpcRequest(FrontendRpcRequest),
-    RpcResultResponse(FrontendRpcResult),
-    RpcResultError(FrontendRpcError),
+/// Parameters for the CallMethod method.
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+pub struct CallMethodParams {
+	/// The method to call inside the interpreter
+	pub method: String,
+
+	/// The parameters for `method`
+	pub params: Vec<Params>,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(rename_all = "snake_case")]
-pub struct FrontendRpcRequest {
-    pub method: String,
-    pub params: Vec<Value>,
+/// Parameters for the Busy method.
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+pub struct BusyParams {
+	/// Whether the backend is busy
+	pub busy: bool,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(rename_all = "snake_case")]
-pub struct FrontendRpcResult {
-    pub id: String,
-    pub result: Value,
+/// Parameters for the ShowMessage method.
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+pub struct ShowMessageParams {
+	/// The message to show to the user.
+	pub message: String,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(rename_all = "snake_case")]
-pub struct FrontendRpcErrorData {
-    pub message: String,
-    pub code: JsonRpcErrorCode,
+/// Parameters for the PromptState method.
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+pub struct PromptStateParams {
+	/// Prompt for primary input.
+	pub input_prompt: String,
+
+	/// Prompt for incomplete input.
+	pub continuation_prompt: String,
 }
 
-#[derive(Debug, Serialize, Deserialize)]
-#[serde(tag = "msg_type", rename_all = "snake_case")]
-pub struct FrontendRpcError {
-    pub id: String,
-    pub error: FrontendRpcErrorData,
+/// Parameters for the WorkingDirectory method.
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+pub struct WorkingDirectoryParams {
+	/// The new working directory
+	pub directory: String,
 }
+
+/**
+ * RPC request types for the frontend comm
+ */
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+#[serde(tag = "method", content = "params")]
+pub enum FrontendRpcRequest {
+	/// Run a method in the interpreter and return the result to the frontend
+	///
+	/// Unlike other RPC methods, `call_method` calls into methods implemented
+	/// in the interpreter and returns the result back to the frontend using
+	/// an implementation-defined serialization scheme.
+	#[serde(rename = "call_method")]
+	CallMethod(CallMethodParams),
+
+}
+
+/**
+ * RPC Reply types for the frontend comm
+ */
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+#[serde(tag = "method", content = "result")]
+pub enum FrontendRpcReply {
+	/// The method result
+	CallMethodReply(CallMethodResult),
+
+}
+
+/**
+ * Front-end events for the frontend comm
+ */
+#[derive(Debug, Serialize, Deserialize, PartialEq)]
+#[serde(tag = "method", content = "params")]
+pub enum FrontendEvent {
+	#[serde(rename = "busy")]
+	Busy(BusyParams),
+
+	#[serde(rename = "show_message")]
+	ShowMessage(ShowMessageParams),
+
+	#[serde(rename = "prompt_state")]
+	PromptState(PromptStateParams),
+
+	#[serde(rename = "working_directory")]
+	WorkingDirectory(WorkingDirectoryParams),
+
+}
+

crates/amalthea/src/comm/help_comm.rs

@@ -9,7 +9,7 @@
 use serde::Deserialize;
 use serde::Serialize;
 
-/// Possible values for the Kind parameter of the ShowHelp method.
+/// Possible values for Kind in ShowHelp
 #[derive(Debug, Serialize, Deserialize, PartialEq)]
 pub enum ShowHelpKind {
 	#[serde(rename = "html")]
@@ -56,6 +56,7 @@ pub enum HelpRpcRequest {
 	/// delivered.
 	#[serde(rename = "show_help_topic")]
 	ShowHelpTopic(ShowHelpTopicParams),
+
 }
 
 /**
@@ -67,6 +68,7 @@ pub enum HelpRpcReply {
 	/// Whether the topic was found and shown. Topics are shown via a Show
 	/// Help notification.
 	ShowHelpTopicReply(bool),
+
 }
 
 /**
@@ -77,5 +79,6 @@ pub enum HelpRpcReply {
 pub enum HelpEvent {
 	#[serde(rename = "show_help")]
 	ShowHelp(ShowHelpParams),
+
 }
 

crates/amalthea/src/comm/plot_comm.rs

@@ -9,13 +9,14 @@
 use serde::Deserialize;
 use serde::Serialize;
 
+/// A rendered plot
 #[derive(Debug, Serialize, Deserialize, PartialEq)]
 pub struct PlotResult {
 	/// The plot data, as a base64-encoded string
 	pub data: String,
 
 	/// The MIME type of the plot data
-	pub mime_type: String,
+	pub mime_type: String
 }
 
 /// Parameters for the Render method.
@@ -43,6 +44,7 @@ pub enum PlotRpcRequest {
 	/// data is returned in a base64-encoded string.
 	#[serde(rename = "render")]
 	Render(RenderParams),
+
 }
 
 /**
@@ -53,6 +55,7 @@ pub enum PlotRpcRequest {
 pub enum PlotRpcReply {
 	/// A rendered plot
 	RenderReply(PlotResult),
+
 }
 
 /**
@@ -63,5 +66,6 @@ pub enum PlotRpcReply {
 pub enum PlotEvent {
 	#[serde(rename = "update")]
 	Update,
+
 }
 

crates/amalthea/src/socket/comm.rs

@@ -9,7 +9,6 @@ use crossbeam::channel::Receiver;
 use crossbeam::channel::Sender;
 use serde::de::DeserializeOwned;
 use serde::Serialize;
-use serde_json::Value;
 
 use crate::comm::base_comm::json_rpc_error;
 use crate::comm::base_comm::JsonRpcErrorCode;
@@ -127,9 +126,21 @@ impl CommSocket {
             Ok(m) => match request_handler(m) {
                 Ok(reply) => match serde_json::to_value(reply) {
                     Ok(value) => value,
-                    Err(err) => self.json_rpc_internal_error(err, data),
+                    Err(err) => json_rpc_error(
+                        JsonRpcErrorCode::InternalError,
+                        format!(
+                            "Failed to process {} request: {err} (request: {data:})",
+                            self.comm_name
+                        ),
+                    ),
                 },
-                Err(err) => self.json_rpc_internal_error(err, data),
+                Err(err) => json_rpc_error(
+                    JsonRpcErrorCode::MethodNotFound,
+                    format!(
+                        "No handler for {} request (method not found): {err:} (request: {data:})",
+                        self.comm_name
+                    ),
+                ),
             },
             Err(err) => json_rpc_error(
                 JsonRpcErrorCode::InvalidRequest,
@@ -144,17 +155,4 @@ impl CommSocket {
         self.outgoing_tx.send(response).unwrap();
         true
     }
-
-    fn json_rpc_internal_error<T>(&self, err: T, data: Value) -> Value
-    where
-        T: std::fmt::Display,
-    {
-        json_rpc_error(
-            JsonRpcErrorCode::InternalError,
-            format!(
-                "Failed to process {} request: {err} (request: {data:})",
-                self.comm_name
-            ),
-        )
-    }
 }

crates/amalthea/src/wire/wire_message.rs

@@ -277,12 +277,7 @@ impl WireMessage {
 
     fn comm_msg_type(data: Option<&Value>) -> String {
         if let Some(Value::Object(map)) = data {
-            if let Some(Value::String(msg_type)) = map.get("msg_type") {
-                if msg_type == "event" {
-                    if let Some(Value::String(event_name)) = map.get("name") {
-                        return String::from(format!("{msg_type}/{event_name}"));
-                    }
-                }
+            if let Some(Value::String(msg_type)) = map.get("method") {
                 return msg_type.clone();
             }
         }

crates/ark/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ark"
-version = "0.1.39"
+version = "0.1.40"
 edition = "2021"
 rust-version = "1.70.0"
 description = """