How to access object from pointer?

Question

I have an application where the user get notified whenever there is a new comment on their post. I'm using parse as a backend.

I have following data structure

Comment table

objectId

Comment

commentedPost

Post table

objectId

createdBy

and I already set a pointer(to PFUser) on installation table called User.

I try to querying the commentedPost>Post>createdBy with User on installation.

I've tried the code below:

Parse.Cloud.afterSave('Comments', function(request) {
commentQuery.include("commentedPost");
var post = request.object.get("commentedPost");
var poster = post.get("createdBy");

var query = new Parse.Query(Parse.Installation);
query.equalTo('jooveUser', poster);

Parse.Push.send({
    where: query, // Set our Installation query.
    data: {
        alert: message = 'hahahahahaha'
    }
}, {
    success: function() {
        response.success();
    },
    error: function(err) {
        response.error();
    }
});
});

But, it does nothing or sending any notifications. What did I do wrong? How can I achieve what I want?

Answer 1

Since you're trying to grab pointer (user) inside the pointer (post) you need to first fetch the post pointer. Small modification to your code (specially pay attention to the fetch().then() part of the code):

Parse.Cloud.afterSave('Comments', function(request) {

    // read pointer async
    request.object.get("commentedPost").fetch().then(function(post){

        // 'post' is the commentedPost object here
        var poster = post.get('createdBy');

        // proceed with the rest of your code - unchanged
        var query = new Parse.Query(Parse.Installation);
        query.equalTo('jooveUser', poster);

        Parse.Push.send({
            where: query, // Set our Installation query.
            data: {
                alert: message = 'hahahahahaha'
            }
        }, {
            success: function() {
                response.success();
            },
            error: function(err) {
                response.error();
            }
        }); 
    });

});    

Let me know if it worked for you.