sync.py

# models mixin
class SyncMixin:
  @classmethod
  def get_sync_type(cls) -> int:
    """Returns sync type."""
    raise NotImplemented()
  
  @classmethod
  def get_sync_model(cls):
    """Returns django.db.Model child class. 
    This model will be used for building queryset for syncronization.
    """
    return cls
  
  @classmethod
  def get_sync_queryset(cls):
    """Returns queryset for selecting rows that updated 
    or created and need synchronization.
    """
    raise NotImplemented()
    
  @classmethod
  def get_deleted_rows_ids():
    """Rerurns ids of the deleted rows."""
    raise NotImplemented()
  

# push sync
def run_push_sync():
  # get models list for synchronization
  models = get_push_sync_model()
  
  for model in models:
    
    # check that exist rows that need synchronization
    if model.need_sync():
      # get queryset for retirieving updated or created rows
      q = model.get_sync_quryset()
      
      # get ids of the deleted rows
      deleted_ids = model.get_deleted_ids()
      
      data = serialize(model_name=model.get_model_name(), q)
      push_data(updated=data, deleted=deleted_ids)
      
# import sync
def run_import_sync():
  models = get_import_sync_models()
  
  data_to_save, data_to_delete = import_data(models)
  
  succeed, fail = save_data(data_to_save)
  
  succeed, fail = delete_data(data_to_delete)
 

# import sync utils
def _get_model(model_label):
    try:
        splitted = model_label.split('.')
        if len(splitted) == 2:
            _, model_name = splitted
        elif len(splitted) == 1:
            model_name = splitted[0]
        else:
            assert False, 'Invalid model label'
        return get_model(model_name)
    except (LookupError, TypeError, AssertionError):
        raise DeserializationError(
            'Invalid model identifier: {}'.format(model_label))


def deserialize(serialized):
    Deserializer.func_globals['_get_model'] = _get_model
    return Deserializer(object_list=serialized, ignorenonexistent=True)
  

def save_data(data):
  for model in data:
    model_name = model['name']
    rows = model['rows']
    for deserialized in deserialize(rows):
      deserialized.save()
    
    
def delete_data(data):
  for model in data:
    model_name = model['name']
    ids = model['ids']
    model_cls = _get_model(model_name)
    model_cls.objects.delete(pk__in=ids)