Data Explorer: Get positron-duckdb extension working on Windows

extensions/positron-duckdb/src/extension.ts

@@ -29,9 +29,10 @@ import {
  TableSchema
 } from './interfaces';
 import * as duckdb from '@duckdb/duckdb-wasm';
+import * as path from 'path';
 import Worker from 'web-worker';
-import { basename, extname, join } from 'path';
 import { Table } from 'apache-arrow';
+import { pathToFileURL } from 'url';
 
 class DuckDBInstance {
  constructor(readonly db: duckdb.AsyncDuckDB, readonly con: duckdb.AsyncDuckDBConnection) { }
@@ -40,12 +41,19 @@ class DuckDBInstance {
  // Create the path to the DuckDB WASM bundle. Note that only the EH
  // bundle for Node is used for now as we don't support Positron
  // extensions running in a browser context yet.
- const distPath = join(ctx.extensionPath, 'node_modules', '@duckdb', 'duckdb-wasm', 'dist');
+ const distPath = path.join(ctx.extensionPath, 'node_modules', '@duckdb', 'duckdb-wasm', 'dist');
  const bundle = {
- mainModule: join(distPath, 'duckdb-eh.wasm'),
- mainWorker: join(distPath, 'duckdb-node-eh.worker.cjs')
+ mainModule: path.join(distPath, 'duckdb-eh.wasm'),
+ mainWorker: path.join(distPath, 'duckdb-node-eh.worker.cjs')
  };
- const logger = new duckdb.VoidLogger();
+
+ // On Windows, we need to call pathToFileURL on mainWorker because the web-worker package
+ // does not support Windows paths that start with a drive letter.
+ if (process.platform === 'win32') {
+ bundle.mainWorker = pathToFileURL(bundle.mainWorker).toString();
+ }
+
+ const logger = new duckdb.ConsoleLogger();
 
  const worker = new Worker(bundle.mainWorker);
 
@@ -81,6 +89,25 @@ const SENTINEL_NAN = 2;
 const SENTINEL_INF = 10;
 const SENTINEL_NEGINF = 10;
 
+function uriToFilePath(uri: string) {
+ // On Windows, we need to fix up the path so that it is recognizable as a drive path.
+ // Not sure how reliable this is, but it seems to work for now.
+ if (process.platform === 'win32') {
+ const filePath = path.parse(uri);
+ // Example: {
+ // root: '/',
+ // dir: '/c:/Users/sharon/qa-example-content/data-files/flights',
+ // base: 'flights.parquet', ext: '.parquet',
+ // name: 'flights'
+ // }
+ if (filePath.root === '/' && filePath.dir.startsWith('/')) {
+ // Remove the leading slash from the path so the path is drive path
+ return uri.substring(1);
+ }
+ }
+ return uri;
+}
+
 /**
  * Implementation of Data Explorer backend protocol using duckdb-wasm,
  * for serving requests coming in through the vscode command.
@@ -129,24 +156,25 @@ export class DataExplorerRpcHandler {
 
  async openDataset(params: OpenDatasetParams): Promise<OpenDatasetResult> {
  const tableName = `positron_${this._tableIndex++}`;
+
  this._uriToTableName.set(params.uri, tableName);
- const fileExt = extname(params.uri);
 
- // console.log(`Opening ${params.uri}`);
+ const filePath = uriToFilePath(params.uri);
+ const fileExt = path.extname(filePath);
 
  let scanOperation;
  switch (fileExt) {
  case '.parquet':
  case '.parq':
- scanOperation = `parquet_scan('${params.uri}')`;
+ scanOperation = `parquet_scan('${filePath}')`;
  break;
  // TODO: Will need to be able to pass CSV / TSV options from the
  // UI at some point.
  case '.csv':
- scanOperation = `read_csv('${params.uri}')`;
+ scanOperation = `read_csv('${filePath}')`;
  break;
  case '.tsv':
- scanOperation = `read_csv('${params.uri}', delim='\t')`;
+ scanOperation = `read_csv('${filePath}', delim='\t')`;
  break;
  default:
  return { error_message: `Unsupported file extension: ${fileExt}` };
@@ -319,7 +347,7 @@ export class DataExplorerRpcHandler {
  async getState(uri: string): RpcResponse<BackendState> {
  const [num_rows, num_columns] = await this._getUnfilteredShape(uri);
  return {
- display_name: basename(uri),
+ display_name: path.basename(uri),
  table_shape: { num_rows, num_columns },
  table_unfiltered_shape: { num_rows, num_columns },
  has_row_labels: false,