Enable VS Code notebooks with a built-in SQL kernel. (#21995)

extensions/ipynb/src/notebookSerializer.ts

@@ -0,0 +1,108 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import * as nbformat from '@jupyterlab/nbformat';
+import * as detectIndent from 'detect-indent';
+import * as vscode from 'vscode';
+import { defaultNotebookFormat } from './constants';
+import { getPreferredLanguage, jupyterNotebookModelToNotebookData } from './deserializers';
+import { createJupyterCellFromNotebookCell, pruneCell, sortObjectPropertiesRecursively } from './serializers';
+import * as fnv from '@enonic/fnv-plus';
+
+export class NotebookSerializer implements vscode.NotebookSerializer {
+	constructor(readonly context: vscode.ExtensionContext) {
+	}
+
+	public async deserializeNotebook(content: Uint8Array, _token: vscode.CancellationToken): Promise<vscode.NotebookData> {
+		let contents = '';
+		try {
+			contents = new TextDecoder().decode(content);
+		} catch {
+		}
+
+		let json = contents && /\S/.test(contents) ? (JSON.parse(contents) as Partial<nbformat.INotebookContent>) : {};
+
+		if (json.__webview_backup) {
+			const backupId = json.__webview_backup;
+			const uri = this.context.globalStorageUri;
+			const folder = uri.with({ path: this.context.globalStorageUri.path.replace('vscode.ipynb', 'ms-toolsai.jupyter') });
+			const fileHash = fnv.fast1a32hex(backupId) as string;
+			const fileName = `${fileHash}.ipynb`;
+			const file = vscode.Uri.joinPath(folder, fileName);
+			const data = await vscode.workspace.fs.readFile(file);
+			json = data ? JSON.parse(data.toString()) : {};
+
+			if (json.contents && typeof json.contents === 'string') {
+				contents = json.contents;
+				json = JSON.parse(contents) as Partial<nbformat.INotebookContent>;
+			}
+		}
+
+		if (json.nbformat && json.nbformat < 4) {
+			throw new Error('Only Jupyter notebooks version 4+ are supported');
+		}
+
+		// Then compute indent from the contents (only use first 1K characters as a perf optimization)
+		const indentAmount = contents ? detectIndent(contents.substring(0, 1_000)).indent : ' ';
+
+		const preferredCellLanguage = getPreferredLanguage(json.metadata);
+		// Ensure we always have a blank cell.
+		if ((json.cells || []).length === 0) {
+			json.cells = [
+				{
+					cell_type: 'code',
+					execution_count: null,
+					metadata: {},
+					outputs: [],
+					source: ''
+				}
+			];
+		}
+
+		// For notebooks without metadata default the language in metadata to the preferred language.
+		if (!json.metadata || (!json.metadata.kernelspec && !json.metadata.language_info)) {
+			json.metadata = json.metadata || { orig_nbformat: defaultNotebookFormat.major };
+			json.metadata.language_info = json.metadata.language_info || { name: preferredCellLanguage };
+		}
+
+		const data = jupyterNotebookModelToNotebookData(
+			json,
+			preferredCellLanguage
+		);
+		data.metadata = data.metadata || {};
+		data.metadata.indentAmount = indentAmount;
+
+		return data;
+	}
+
+	public serializeNotebook(data: vscode.NotebookData, _token: vscode.CancellationToken): Uint8Array {
+		return new TextEncoder().encode(this.serializeNotebookToString(data));
+	}
+
+	public serializeNotebookToString(data: vscode.NotebookData): string {
+		const notebookContent = getNotebookMetadata(data);
+		// use the preferred language from document metadata or the first cell language as the notebook preferred cell language
+		const preferredCellLanguage = notebookContent.metadata?.language_info?.name ?? data.cells[0].languageId;
+
+		notebookContent.cells = data.cells
+			.map(cell => createJupyterCellFromNotebookCell(cell, preferredCellLanguage))
+			.map(pruneCell);
+
+		const indentAmount = data.metadata && 'indentAmount' in data.metadata && typeof data.metadata.indentAmount === 'string' ?
+			data.metadata.indentAmount :
+			' ';
+		// ipynb always ends with a trailing new line (we add this so that SCMs do not show unnecesary changes, resulting from a missing trailing new line).
+		return JSON.stringify(sortObjectPropertiesRecursively(notebookContent), undefined, indentAmount) + '\n';
+	}
+}
+
+export function getNotebookMetadata(document: vscode.NotebookDocument | vscode.NotebookData) {
+	const notebookContent: Partial<nbformat.INotebookContent> = document.metadata?.custom || {};
+	notebookContent.cells = notebookContent.cells || [];
+	notebookContent.nbformat = notebookContent.nbformat || 4;
+	notebookContent.nbformat_minor = notebookContent.nbformat_minor ?? 2;
+	notebookContent.metadata = notebookContent.metadata || { orig_nbformat: 4 };
+	return notebookContent;
+}