Metapost: Current Comments

By popular request, we finally have a comment widget on the side that will only post the most current comment per "active thread", instead of having a half dozen XYZ commented on the Twilight thread of the week. I owe much gratitude to Husband, who basically devoted his entire day to this and who does not, technically, know Javascript despite being able to code me up a widget on short notice. Husband is awesome.







Quirks of this script include:

• The widget may display between 1 and 25 "current comments". The deciding factor here is the 25 comments contained in the RSS blog feed page that the widget is loading.
• The widget may display less than 25 comments. The deciding factor here is comment density: if the last 25 comments on the blog were on a Twilight post, only 1 comment will show. 
• The widget displays a piece of the web address title, and not the actual blogger title. This is a quirk of the RSS blog feed page and cannot be changed no matter how much it bugs me. 
• The widget guts were recycled from a snipped posted by the ReviewOfWeb folks, credited in the widget, who are quite clearly also awesome.

For those of you who use Blogger -- and I think this widget will only work with Blogger feeds, but I could be wrong -- here is the final code. Feel free to reuse.

<script style="text/javascript">
  // Global array variable to control for post uniqueness.
  arr = new Array(25);

  // Array function. Returns true when post already exists.
  function ArrayContains(arr, title)
  {
    for (index = 0; index < arr.length; index++)
    {
      if (arr[index] == title)
      {
        return true;
      }
    }
    return false;
  }

  // Comment function.
  function showrecentcomments(json)
  {
    // Set to 25 to process full feed.
    var numcomments = 25;

    // Increment through each feed item.
    for (var i = 0; i < numcomments; i++)
    {
      var entry = json.feed.entry[i];
      var alturl;
      if (i == json.feed.entry.length) break;
      for (var k = 0; k < entry.link.length; k++)
      {
        if (entry.link[k].rel == 'alternate')
        {
          alturl = entry.link[k].href;
          break;
        }
      }

      // Get post url to check for uniqueness.
      checkurl = alturl.split("?");
      checkurl = checkurl[0];

      // If post has already been processed, skip to next in loop.
      if (ArrayContains(arr, checkurl))
      {
        continue;
      }

      // Else continue processing.
      else
      {
        var linktext = checkurl.split("/");
        linktext = linktext[5];
        // Limit substring to keep on one line.
        linktext = linktext.substr(0,30).link(checkurl);
        if ("content" in entry)
        {
          var comment = entry.content.$t;
        }
        else
        if ("summary" in entry)
        {
          var comment = entry.summary.$t;
        }
        else var comment = "";
        var re = /<\S[^>]*>/g;
        comment = comment.replace(re, "");
        document.write('<br/>');
        document.write('<b>' + entry.author[0].name.$t + '</b> commented on <br/>');
        document.write(linktext);
        document.write('<br/>');

        // Add checkurl to global array now that the post has been processed.
        arr[i] = checkurl;
      }
    }
    document.write('<br/>');
  }
</script>
<script src="http://anamardoll.com/feeds/comments/default?alt=json-in-script&callback=showrecentcomments"></script>
<font color="999999"><a href="http://reviewofweb.com/blogging/recent-comments-blogspot-widget/" style="color: rgb(153,153,153)">Widget </a>by <a href="http://reviewofweb.com/" style="color: rgb(153,153,153)">ReviewOfWeb</a></font>