cantina-embedly.js

var request = require('request')
  , _ = require('underscore');

module.exports = function (app) {

  app.embedly = module.exports = {
    fetch: fetch
  };

  // Default conf.
  app.conf.add({
    embedly: {
      url: 'http://api.embed.ly/1/oembed'
    }
  });

  // Grab embedly conf.
  var conf = app.conf.get('embedly');
  var options = {
    uri: conf.url,
    qs: {
      key: conf.key
    }
  };
  _.defaults(options.qs, conf.options);

  function fetch (url, callback) {
    options.qs.url = rewrite(url);

    request(options, function (error, response, body) {
      if (error) return callback(error);
      if (response.statusCode !== 200) return callback(new Error('EMBEDLY_HTTP_ERROR: ' + response.statusCode));
      if (!body) return callback(new Error('EMBEDLY_NO_BODY'));
      if (typeof body === 'string') {
        try {
          body = JSON.parse(body);
          Object.keys(body).forEach(function (key) {
            if(body[key] && typeof body[key] === 'string'){
              if (['meta', 'oembed', 'open_graph', 'place'].indexOf(key) >= 0) {
                body[key] = JSON.parse(body[key]);
              }
            }
          });
        } catch (e) {
          return callback(e);
        }
      }
      body.thumbnail_html = getThumbnailHtml(body);
      return callback(null, body);
    });
  }

  function rewrite (url) {
    // CNN's RSS feeds are powered by FeedBurner
    // This obfuscates the "real" url with a crap redirect link that Embedly can't
    // do anything with. But the RSS feed also contains the original url, and
    // smart sharing tools will use that url. This is better, but even that
    // "real" url is not the canonical url, Embedly still can't do anything useful
    // with it. Luckily, *we* know CNN's real-url-munging algorithm, so at least
    // if we get that "real" url, we can rewrite it into the canonical url, which
    // Embedly CAN deal with.
    //
    // WOOT!!!!
    if (url.match(/cnn.com/) && url.match(/\/video\//)) {
      return url.replace('#', 'data/2.0') + '.html';
    }
    return url;
  }

  /**
   * Parse Embed.ly JSON depending on the "type" of link and
   * return a basic formatted HTML string with the appropriate
   * thumbnail image or video embed
   *
   * @param {Object}
   * @return {String}
   */
  function getThumbnailHtml (data) {
    var output = '';
    switch(data.type) {
    case 'link':
      if (data.thumbnail_url) {
        output = '<img src="' + data.thumbnail_url + '"';
        if (data.thumbnail_width) {
          output += ' width="' + data.thumbnail_width + '"';
        }
        if (data.thumbnail_height) {
          output += ' height="' + data.thumbnail_height + '"';
        }
        output += '/>';
      }
      break;
    case 'photo':
      // According to the Embed.ly docs,
      // for the 'photo' type, there will **always** be url, width and height
      output = '<img src="' + data.url + '" width="' + data.width + '" height="' + data.height + '"/>';
      break;
    case 'rich':
    case 'video':
      output = data.html;
      break;
    }
    return output;
  }
};