Programmatic way to run "Attach External R Session"?

[katrinabrock]

Previously, I used .vsc.attach() to connect the extension to a running session.

I see there is now a way to do this that involves running a vsc command and pasting: https://github.com/REditorSupport/vscode-R/wiki/Interacting-with-R-terminals#using-self-managed-r-terminals

I find the new way a bit cumbersome. Is there any way to do this programmatically directly from R? In particular, I use the R debugger extension and previously I could have those sessions automatically attach when they launch, but now it seems I'll have to manually run a key sequence each time I rerun my code and start the debugger. Is there any faster way?

EDIT: workaround

I was able to get "Attach to Debugger" down to one shortcut using the Commands Extension.

settings.json

    "commands.commands": {
        "R Custom: Attach to debugger": {
            "sequence": [
                { "command": "r.connectToSession" },
                { "command": "workbench.debug.action.focusRepl" },
                { "command": "editor.action.clipboardPasteAction" },
                { "command": "repl.action.acceptInput" }
            ]
        }
    }

keybindings.json

    {
        "key": "shift+cmd+a",
        "command": "R Custom: Attach to debugger",
        "when": "inDebugMode"
    }

Would still be nice to have a way to call this from R.

[Alox1d]

The R-side entry point is now sess::connect(). With the matching bundled sess package available, check whether your debugger session inherits the endpoint:

Sys.getenv(c("SESS_ENDPOINT", "SESS_DISCOVERY_FILE"))
sess::connect()

If both variables are empty, you need to pass the current window's endpoint explicitly. It doesn't discover an arbitrary VS Code window automatically. The copied source(...) command also prepares the bundled package, so that setup still matters. Session API.

[jamalkamaladdin]

Workaround: run R: Attach External R Session once per window. It writes an attach script that lives until your window closes or reloads. Source newest script from your debugged code, macOS path shown:

f <- Sys.glob("~/Library/Application Support/Code/User/globalStorage/reditorsupport.r/tmp/attach/vscode-r-*.R")
if (length(f)) source(f[which.max(file.mtime(f))])

Script path:

vscode-R/src/session.ts

Lines 1226 to 1229 in e2b28f1

	function getAttachSessionScriptPath(pipePath: string): string {
	const scriptBase = path.basename(pipePath).replace(/[^a-zA-Z0-9_.-]/g, '_') || 'attach_session';
	return path.join(extensionContext.globalStorageUri.fsPath, 'tmp', 'attach', `${scriptBase}.R`);
	}

[katrinabrock]

Thanks! That's very helpful. I wonder if there's a way to get the script creation process to run when vscode starts on an R project to eliminate even that manual step.

For any future readers with the same problem. Path on linux (as remote) seems to be "~/.vscode-server/data/User/globalStorage/reditorsupport.r/tmp/attach/vscode-r-*.R".

[Alox1d]

@katrinabrock I checked current main: startup initializes the session server and refreshes discovery files, but does not create that .R script. The script is generated when an attach action requests its command.

I could not find a setting to generate it automatically at project startup. Adding that behavior inside the extension would need a startup hook. The path uses VS Code's globalStorageUri, which is consistent with the remote-server location you found. This is from the current source; I have not tested it on your remote setup.