Parse.com Cloud Code - Creating new Instance of another object on before save

Question

I have two classes, Groups and memberships. When a group is made, I'd like its corresponding membership to be made as well. I attempt to do so like this:

Parse.Cloud.beforeSave("Group", function(request, response) {   
    var name = request.object.get("name");

    if (!name) {
        response.error("A Group must have a name");
    } else {
        if (!(/^\w+$/i.test(name))){
            response.error("Only letters and numbers, please.");
        }
        var query = new Parse.Query("Group");
        query.equalTo("name", name);
        query.first({
            success: function(object) {
                if (object) {
                    response.error("A group with this name exists.");
                } else {
                    createMembershipForGroup(request.object, Parse.User);
                    response.success();
                }
            },
            error: function(error) {
                response.error("Could not validate Uniqueness");
            }
        });
    }
});

createMembershipForGroup = function(group, user) {
    var MembershipClass = Parse.Object.extend("Membership");
    var membership = new MembershipClass();

    membership.set("group", group);
    membership.set("user", user);
    membership.save(null,{
      success:function(membership) { 
        response.success(membership);
      },
      error:function(error) {
        response.error(error);
      }
    });
}

I receive an error back, saying the following:

E2014-05-06T21:40:10.740Z] v30: before_save triggered for Group for user xgzDnZ9h0A Input: {"original":null,"update":{"admin":{"objectId":"xgzDnZ9h0A","className":"_User","__type":"Pointer"},"name":"test","public":false}} Result: undefined

Not too sure what the error is. How could I go about debugging code like this so I can isolate the issue easily?

Answer 1

Let beforeSave handle only the validation, and move your membership code to afterSave. The problem is probably that you're trying to store a relation to an object that is not yet saved (as you're in beforeSave, the object does not yet have an objectId)

Answer 2

problem is you are trying to call an async function and leaves before wait to complete it.

createMembershipForGroup(request.object, Parse.User);//Calling async func
response.success();//Leaves beforeSave function

You should write your createMembershipForGroup function inside success response of your query and return your response.success() method in here

membership.save(null,{
  success:function(membership) { 
    response.success(membership); // this should be response of beforeSave
  },
  error:function(error) {
    response.error(error);
  }
});

I will post working code if this not helps.