Multi-level objects - destructive merge based off keys

Question

I have two objects. Basically a model and data situation. Can't figure out how to recursively delete items in the data object, that have been removed from the model.

First is the model:

var foo = {
  "title": "Enter title",
  "info": {
    "released": "Enter year",
    "runtime": "Enter time"
  }
}

The other one is the data:

var bar = {
  "title": "Forrest Gump",
  "info": {
    "released": "1994",
    "runtime": "02:22",
    "awards": "3"
  }
  "genre": "Drama/Comedy-drama"
}

I'm trying to do a generic comparison between two objects that would result in:

var bar = {
  "title": "Forrest Gump",
  "info": {
    "released": "1994",
    "runtime": "02:22"
  }
}

Any help would be very appreciated!

A super bonus would be if it would be able to add object keys+values that exist in the blueprint but not in the data. I have that working separately, but it would be a nice bonus!

Answer 1

A recursive function over Object.keys should work perfectly:

var foo = {
  "title": "Enter title",
  "info": {
    "released": "Enter year",
    "runtime": "Enter time"
  }
};

var bar = {
  "title": "Forrest Gump",
  "info": {
    "released": "1994",
    "runtime": "02:22",
    "awards": "3"
  },
  "genre": "Drama/Comedy-drama"
}

function getBoth(base, data) {
  var result = {};
  Object.keys(base).forEach(key => {
    if (typeof base[key] == "object" && data[key]) {
      result[key] = getBoth(base[key], data[key]);
    } else if (data[key]) {
      result[key] = data[key];
    }
  });
  return result;
}

console.log(getBoth(foo, bar));