Parse.com CloudCode, unable to debug error

Question

A bit new to JS. I'm using Parse.com's CloudCode in order to calculate the "score" of a "Post" instance. I retrieve any "Votes" associated with a post, and then sum up their "value", then return that value.

Parse.Cloud.define("postScore", function(request, response) {  

    var postId = request.params.postId;
    var post = Parse.Object.extend("Post");
    post.id = postId;

    var query = new Parse.Query("Vote");
    query.equalTo("post", post);

    query.find({
        success: function(results) {
          var sum = 0;
          for (var i = 0; i < results.length; ++i) {
            sum += results[i].get("value");
          }
          response.success(sum);
        },
        error: function() {
          response.error("Could not calculate value");
        }
      });
});

Getting this error:

2014-05-02 19:21:09.124 XXX[33361:2d3b] Error: undefined (Code: 141, Version: 1.2.19)

Not too sure what the issue is.

Calling it in my iOS app like so:

- (void)fetchPostScores
{
  for (BVYPost *post in _postsArray) {
    [PFCloud callFunctionInBackground:@"postScore" withParameters:@{@"postId": post.objectId} block:^(NSNumber *score, NSError *error) {
      if (!error) {
        post.score = score;
      }
    }];
  }
}

Answer 1

This is wrong:

var post = Parse.Object.extend("Post");
post.id = postId;

The correct syntax would be:

var post = new Parse.Object("Post");
post.id = postId;