MongoDB: Update nested data, but avoid multiple objects

Question

I try to insert some data into an existing document:

Graph.update(
    { id: id }, 
    {
        $push: {
            tooltips: {
                element: Session.get('tooltipID'),
                text: text
            }
        }
    }
);

This is working quite well, but if there is already data in tooltips, this one should be updated instead of adding a new object, as there can only be a unique object for a unique element (tooltipID).

I want to avoid these multiple entries for the same element-value in tooltips.

{
    "_id" : "c4bKur6TKcgFHGLZZ",
    "data" : "[]",
    "tooltips" : [
        {
            "element" : "2d4edaaf",
            "text" : "Lorem"
        },
        {
            "element" : "2d4edaaf",
            "text" : "ipsum"
        }
    ]
}

But it should be possible to have more then one object in tooltips, if element is really unique...

I tried to add a upsert:true to the update(), but that doesn't work.

Answer 1

Definitely upsert won't work with embedded document.

One approach can be

Graph.update({id:id}, 
    {
       $addToSet: {
           'tooltips': {
              element: Session.get('tooltipID'),
              text: text
            }
       }
})

It will ensure no duplicate on tooltips;

similarly you can use $set

Graph.update({
  id:id,
 'tooltips.element': Session.get('tooltipID')
  }, 
  {
 $set: {
    'tooltips.$.text':text
   }
})

or you can pull before push

Graph.update({
    "id":id
}, {
    $pull: {
        'tooltips': {
            "element": Session.get('tooltipID')
        }
    }
})
    Graph.update(
    { id: id }, 
    {
        $push: {
            tooltips: {
                element: Session.get('tooltipID'),
                text: text
            }
        }
    }
);