code: func getDiff(baseData, newData *simplejson.Json) (interface{}, diff.Diff, error) {
  	leftBytes, err := baseData.Encode()
  	if err != nil {
  		return nil, nil, err
  	}
  
  	rightBytes, err := newData.Encode()
  	if err != nil {
  		return nil, nil, err
  	}
  
  	jsonDiff, err := diff.New().Compare(leftBytes, rightBytes)
  	if err != nil {
  		return nil, nil, err
  	}
  
  	if !jsonDiff.Modified() {
  		return nil, nil, ErrNilDiff
  	}
  
  	left := make(map[string]interface{})
  	err = json.Unmarshal(leftBytes, &left)
  	if err != nil {
  		return nil, nil, err
  	}
  
  	return left, jsonDiff, nil
  }
docs: // getDiff computes the diff of two dashboard versions.