Download images that are attached in the comments of a specific GitHub issue

get-issue-images.js

/**
 * Get the files attached on a GitHub issue and its comments
 *
 * @see https://developer.github.com/v3/issues/comments/#list-comments-on-an-issue
 * @see https://developer.github.com/v3/media/#comment-body-properties
 */
'use strict';

const fs = require('fs');
const got = require('got');

const token = process.env.GITHUB_TOKEN;

const ghOptions = {
  headers: {
    'user-agent': 'Get Issue Comments Tool',
    authorization: 'token ' + token,
    accept: 'application/vnd.github.full+json'
  },
  json: true
};

// https://github.com/nodejs/evangelism/issues/179
var owner = 'nodejs',
  repo = 'evangelism',
  issue = 179;


// GET /repos/:owner/:repo/issues/:number/comments
var url = 'https://api.github.com/repos/' + owner + '/' + repo + '/issues/' + issue + '/comments';

got(url, ghOptions, (error, body, response) => {
  if (error) {
    console.log(error.response.body);
  }
  else {
    fs.writeFileSync('comments.json', JSON.stringify(body, null, '  '), 'utf8');
    var bodies = processComments(body);
    var images = findImages(bodies);
    console.log('Found ' + images.length + ' images in ' + bodies.length + ' comments');
    downloadImages(images);
  }
});

function processComments(data) {
  return data.map(function (item) {
    return item.body;
  });
}

function findImages(data) {
  var images = [],
    re = /[\/\:\w-_\.]+\.(png|jpg)/g;

  data.forEach(function (item) {
    var list;
    while ((list = re.exec(item)) !== null) {
      images.push(list[0]);
    }
  });

  return images;
}

function downloadImages(list) {
  list.forEach(function (item) {
    var name = path.basename(item);
    got(item, {stream: true}).pipe(fs.createWriteStream(name));
  });
}