Notebooks: Support User-Installed Kernels (#10194)

* Fixes for attach to. Still need to update cache

* Don't have jupyter hardcoded

* Handle DOTNET_ROOT env var

* Fix on load

* Put behind feature flag

* Cleanup

* Error check

* PR feedback

extensions/notebook/src/jupyter/jupyterServerInstallation.ts

@@ -332,6 +332,12 @@ export class JupyterServerInstallation implements IJupyterServerInstallation {
 		let env = Object.assign({}, process.env);
 		delete env['Path']; // Delete extra 'Path' variable for Windows, just in case.
 		env['PATH'] = this.pythonEnvVarPath;
+
+		// We don't want Jupyter to know about DOTNET_ROOT, as it's been modified by the liveshare experience
+		// Without this, won't be able to find the ASP.NET bits
+		if (process.env['DOTNET_ROOT']) {
+			delete env['DOTNET_ROOT'];
+		}
 		this.execOptions = {
 			env: env
 		};

extensions/notebook/src/jupyter/jupyterSessionManager.ts

@@ -108,6 +108,11 @@ export class JupyterSessionManager implements nb.SessionManager {
 			// TODO add more info to kernels
 			return kernel;
 		});
+
+		// For now, need to remove PySpark3, as it's been deprecated
+		// May want to have a formalized deprecated kernels mechanism in the future
+		kernels = kernels.filter(k => k.name !== 'pyspark3kernel');
+
 		let allKernels: nb.IAllKernels = {
 			defaultKernel: specs.default,
 			kernels: kernels
@@ -343,6 +348,11 @@ export class JupyterSession implements nb.ISession {
 			}
 			for (let i = 0; i < Object.keys(process.env).length; i++) {
 				let key = Object.keys(process.env)[i];
+				// DOTNET_ROOT gets set as part of the liveshare experience, but confuses the dotnet interactive kernel
+				// Not setting this environment variable for notebooks removes this issue
+				if (key.toLowerCase() === 'dotnet_root') {
+					continue;
+				}
 				if (key.toLowerCase() === 'path' && this._pythonEnvVarPath) {
 					allCode += `%set_env ${key}=${this._pythonEnvVarPath}${EOL}`;
 				} else {