SQL Kernel Improvements/Removing Spark Code from Core/Attach to Changes (#3790)

* Scenarios work besides loading saved kernel

* Fix compilation issue

* Save and load functional

* Fix loading kernesl issue when sql kernel is not enabled

* Fix language mapping to not be hardcoded any longer

* Remove unnecessary comment

* PR Comments vol. 1

* Code cleanup, use ConnectionProfile instead of IConnectionProfile when accessing serverName

* PR changes vol. 2

* One final comment for PR

* Fix linting issue

src/sql/workbench/services/notebook/common/notebookServiceImpl.ts

@@ -80,6 +80,7 @@ export class NotebookService extends Disposable implements INotebookService {
 	private _onNotebookEditorRename = new Emitter<INotebookEditor>();
 	private _editors = new Map<string, INotebookEditor>();
 	private _fileToProviders = new Map<string, NotebookProviderRegistration[]>();
+	private _providerToStandardKernels = new Map<string, nb.IStandardKernel[]>();
 	private _registrationComplete = new Deferred<void>();
 	private _isRegistrationComplete = false;
 
@@ -121,6 +122,9 @@ export class NotebookService extends Disposable implements INotebookService {
 				this.addFileProvider(registration.fileExtensions, registration);
 			}
 		}
+		if (registration.standardKernels) {
+			this.addStandardKernels(registration);
+		}
 	}
 
 	registerProvider(providerId: string, instance: INotebookProvider): void {
@@ -154,6 +158,26 @@ export class NotebookService extends Disposable implements INotebookService {
 		this._fileToProviders.set(fileType.toUpperCase(), providers);
 	}
 
+	// Standard kernels are contributed where a list of kernels are defined that can be shown
+	// in the kernels dropdown list before a SessionManager has been started; this way,
+	// every NotebookProvider doesn't need to have an active SessionManager in order to contribute
+	// kernels to the dropdown
+	private addStandardKernels(provider: NotebookProviderRegistration) {
+		let providerUpperCase = provider.provider.toUpperCase();
+		let standardKernels = this._providerToStandardKernels.get(providerUpperCase);
+		if (!standardKernels) {
+			standardKernels = [];
+		}
+		if (Array.isArray(provider.standardKernels)) {
+			provider.standardKernels.forEach(kernel => {
+				standardKernels.push(kernel);
+			});
+		} else {
+			standardKernels.push(provider.standardKernels);
+		}
+		this._providerToStandardKernels.set(providerUpperCase, standardKernels);
+	}
+
 	getSupportedFileExtensions(): string[] {
 		return Array.from(this._fileToProviders.keys());
 	}
@@ -165,6 +189,10 @@ export class NotebookService extends Disposable implements INotebookService {
 		return providers ? providers.map(provider => provider.provider) : undefined;
 	}
 
+	getStandardKernelsForProvider(provider: string): nb.IStandardKernel[] {
+		return this._providerToStandardKernels.get(provider.toUpperCase());
+	}
+
 	public shutdown(): void {
 		this._managersMap.forEach(manager => {
 			manager.forEach(m => {
@@ -337,7 +365,7 @@ export class NotebookService extends Disposable implements INotebookService {
 			notebookRegistry.registerNotebookProvider({
 				provider: sqlProvider.providerId,
 				fileExtensions: DEFAULT_NOTEBOOK_FILETYPE,
-				standardKernels: ['SQL']
+				standardKernels: { name: 'SQL', connectionProviderIds: ['MSSQL'] }
 			});
 		}
 	}
@@ -444,5 +472,4 @@ export class SqlNotebookManager implements INotebookManager {
 	public get sessionManager(): nb.SessionManager {
 		return this._sessionManager;
 	}
-
 }