lens/src/common/utils/tar.ts

/**
 * Copyright (c) 2021 OpenLens Authors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

// Helper for working with tarball files (.tar, .tgz)
// Docs: https://github.com/npm/node-tar
import tar, { ExtractOptions, FileStat } from "tar";
import path from "path";

export interface ReadFileFromTarOpts {
  tarPath: string;
  filePath: string;
  parseJson?: boolean;
}

export function readFileFromTar<R = Buffer>({ tarPath, filePath, parseJson }: ReadFileFromTarOpts): Promise<R> {
  return new Promise(async (resolve, reject) => {
    const fileChunks: Buffer[] = [];

    await tar.list({
      file: tarPath,
      filter: entryPath => path.normalize(entryPath) === filePath,
      onentry(entry: FileStat) {
        entry.on("data", chunk => {
          fileChunks.push(chunk);
        });
        entry.once("error", err => {
          reject(new Error(`reading file has failed ${entry.path}: ${err}`));
        });
        entry.once("end", () => {
          const data = Buffer.concat(fileChunks);
          const result = parseJson ? JSON.parse(data.toString("utf8")) : data;

          resolve(result);
        });
      },
    });

    if (!fileChunks.length) {
      reject(new Error("Not found"));
    }
  });
}

export async function listTarEntries(filePath: string): Promise<string[]> {
  const entries: string[] = [];

  await tar.list({
    file: filePath,
    onentry: (entry: FileStat) => {
      entries.push(path.normalize(entry.path as any as string));
    },
  });

  return entries;
}

export function extractTar(filePath: string, opts: ExtractOptions & { sync?: boolean } = {}) {
  return tar.extract({
    file: filePath,
    cwd: path.dirname(filePath),
    ...opts,
  });
}