Add sample Notebook provider (#17988)

samples/sample-notebook-provider/src/sampleSerializer.ts

@@ -0,0 +1,35 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as vscode from 'vscode';
+
+/**
+ * Sample hardcoded contents for the Notebook.
+ */
+const presetNotebookData: vscode.NotebookData = {
+	cells: [{
+		kind: vscode.NotebookCellKind.Markup,
+		value: 'Sample markup cell',
+		languageId: 'Markup'
+	}, {
+		kind: vscode.NotebookCellKind.Code,
+		value: '1+1',
+		languageId: 'Python'
+	}]
+};
+
+const presetNotebookBytes = new TextEncoder().encode(JSON.stringify(presetNotebookData));
+
+/**
+ * A sample Notebook serializer which handles serializing/deserializing the Notebook from/into a byte array for storage.
+ */
+export class SampleSerializer implements vscode.NotebookSerializer {
+	deserializeNotebook(content: Uint8Array, token: vscode.CancellationToken): vscode.NotebookData | Thenable<vscode.NotebookData> {
+		return presetNotebookData;
+	}
+	serializeNotebook(data: vscode.NotebookData, token: vscode.CancellationToken): Uint8Array | Thenable<Uint8Array> {
+		return presetNotebookBytes;
+	}
+}