Remove the slack formatting on URL's, email addresses, channels, groups and user ids.

removeFormatting.js

function removeSlackFormatting(input)
{
  var text = input;
  text = text.replace(/<([@#!])?([^>|]+)(?:\|([^>]+))?>/g, (function(_this) {
    return function(m, type, link, label) {
      var channel, user;
      switch (type) {
        case '@':
          if (label) {
            return label;
          }
          user = _this.client.getUserByID(link);
          if (user) {
            return "@" + user.name;
          }
          break;
        case '#':
          if (label) {
            return label;
          }
          channel = _this.client.getChannelByID(link);
          if (channel) {
            return "\#" + channel.name;
          }
          break;
        case '!':
          if (link === 'channel' || link === 'group' || link === 'everyone') {
            return "@" + link;
          }
          break;
        default:
          link = link.replace(/^mailto:/, '');
          if (label && -1 === link.indexOf(label)) {
            return label + " (" + link + ")";
          } else {
            return link;
          }
      }
    };
  })(this));
  text = text.replace(/&lt;/g, '<');
  text = text.replace(/&gt;/g, '>');
  text = text.replace(/&amp;/g, '&');

  return text;
}