utils.ts

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.

import {WriteStream} from 'fs';
import * as https from 'https';
import {JSZipObject} from 'jszip';

export const downloadZip = async(url: string): Promise<Buffer> => new Promise<Buffer>((resolve, reject) => {
  https.get(url, res => {
    const {statusCode} = res;
    const contentType = res.headers['content-type'];

    if (statusCode === 301 || statusCode === 302) {
      downloadZip(res.headers.location!).then(buffer => resolve(buffer), reason => reject(reason));
      return;
    } else if (statusCode !== 200) {
      throw new Error(`Failed to download build list. HTTP status code = ${statusCode}`);
    }
    if (!contentType || !/^application\/zip/.test(contentType)) {
      throw new Error(`unexpected content type: ${contentType}`);
    }

    const chunks: Buffer[] = [];
    res.on('data', (chunk) => {
      chunks.push(chunk);
    });
    res.on('end', () => {
      resolve(Buffer.concat(chunks));
    });
    res.on('error', err => {
      reject(`${err}`);
    });
  });
});

export const extractFile = async(entry: JSZipObject, ostream: WriteStream): Promise<void> =>
    new Promise<void>((resolve, reject) => {
      entry.nodeStream()
          .pipe(ostream)
          .on('finish',
              () => {
                resolve();
              })
          .on('error', (err) => {
            reject(err);
          });
    });