Add support for retrieving metadata for an specific comm. (#589)

crates/amalthea/src/comm/connections_comm.rs

@@ -31,6 +31,26 @@ pub struct FieldSchema {
 	pub dtype: String
 }
 
+/// MetadataSchema in Schemas
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
+pub struct MetadataSchema {
+	/// Connection name
+	pub name: String,
+
+	/// Language ID for the connections. Essentially just R or python
+	pub language_id: String,
+
+	/// Connection host
+	pub host: Option<String>,
+
+	/// Connection type
+	#[serde(rename = "type")]
+	pub metadata_schema_type: Option<String>,
+
+	/// Code used to re-create the connection
+	pub code: Option<String>
+}
+
 /// Parameters for the ListObjects method.
 #[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
 pub struct ListObjectsParams {
@@ -66,6 +86,13 @@ pub struct PreviewObjectParams {
 	pub path: Vec<ObjectSchema>,
 }
 
+/// Parameters for the GetMetadata method.
+#[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
+pub struct GetMetadataParams {
+	/// The comm_id of the client we want to retrieve metdata for.
+	pub comm_id: String,
+}
+
 /**
  * Backend RPC request types for the connections comm
  */
@@ -103,6 +130,12 @@ pub enum ConnectionsBackendRequest {
 	#[serde(rename = "preview_object")]
 	PreviewObject(PreviewObjectParams),
 
+	/// Gets metadata from the connections
+	///
+	/// A connection has tied metadata such as an icon, the host, etc.
+	#[serde(rename = "get_metadata")]
+	GetMetadata(GetMetadataParams),
+
 }
 
 /**
@@ -125,6 +158,8 @@ pub enum ConnectionsBackendReply {
 
 	PreviewObjectReply(),
 
+	GetMetadataReply(MetadataSchema),
+
 }
 
 /**

crates/ark/src/connections/r_connection.rs

@@ -4,20 +4,25 @@
 // Copyright (C) 2023 by Posit Software, PBC
 //
 
+use std::collections::HashMap;
+
 use amalthea::comm::comm_channel::CommMsg;
 use amalthea::comm::connections_comm::ConnectionsBackendReply;
 use amalthea::comm::connections_comm::ConnectionsBackendRequest;
 use amalthea::comm::connections_comm::ConnectionsFrontendEvent;
 use amalthea::comm::connections_comm::ContainsDataParams;
 use amalthea::comm::connections_comm::FieldSchema;
 use amalthea::comm::connections_comm::GetIconParams;
+use amalthea::comm::connections_comm::GetMetadataParams;
 use amalthea::comm::connections_comm::ListFieldsParams;
 use amalthea::comm::connections_comm::ListObjectsParams;
+use amalthea::comm::connections_comm::MetadataSchema;
 use amalthea::comm::connections_comm::ObjectSchema;
 use amalthea::comm::connections_comm::PreviewObjectParams;
 use amalthea::comm::event::CommManagerEvent;
 use amalthea::socket::comm::CommInitiator;
 use amalthea::socket::comm::CommSocket;
+use anyhow::anyhow;
 use crossbeam::channel::Sender;
 use harp::exec::RFunction;
 use harp::exec::RFunctionExt;
@@ -32,6 +37,7 @@ use stdext::unwrap;
 use uuid::Uuid;
 
 use crate::interface::RMain;
+use crate::modules::ARK_ENVS;
 use crate::r_task;
 
 #[derive(Deserialize, Serialize, Clone)]
@@ -216,6 +222,29 @@ impl RConnection {
                 })?;
                 Ok(ConnectionsBackendReply::ContainsDataReply(contains_data))
             },
+            ConnectionsBackendRequest::GetMetadata(GetMetadataParams { comm_id }) => {
+                let metadata = r_task(|| -> Result<_, anyhow::Error> {
+                    let r_metadata: HashMap<String, String> =
+                        RFunction::new("", ".ps.connection_metadata")
+                            .add(comm_id)
+                            .call_in(ARK_ENVS.positron_ns)?
+                            .try_into()?;
+
+                    let schema = MetadataSchema {
+                        language_id: String::from("r"),
+                        name: r_metadata
+                            .get("displayName")
+                            .ok_or(anyhow!("Need a display name"))?
+                            .clone(),
+                        host: r_metadata.get("host").cloned(),
+                        metadata_schema_type: r_metadata.get("type").cloned(),
+                        code: r_metadata.get("connectionCode").cloned(),
+                    };
+
+                    Ok(schema)
+                })?;
+                Ok(ConnectionsBackendReply::GetMetadataReply(metadata))
+            },
         }
     }
 

crates/ark/src/modules/positron/connection.R

@@ -188,6 +188,21 @@ connection_flatten_object_types <- function(object_tree) {
     identical(object_types$contains, "data")
 }
 
+.ps.connection_metadata <- function(id) {
+    con <- get(id, getOption("connectionObserver")$.connections)
+
+    if (is.null(con)) {
+        stop("Expected a valid comm_id")
+    }
+
+    list(
+        type = con$type,
+        host = con$host,
+        displayName = con$displayName,
+        connectCode = con$connectCode
+    )
+}
+
 .ps.register_dummy_connection <- function() {
     # This is used for testing the connections service
     observer <- getOption("connectionObserver")