chore: consolidate dashboard import logic (#11529)

* Consolidate dash import logic

* Fix lint

* Remove Slice.import_obj

* Remove unused import

* Fix log

superset/utils/dashboard_import_export.py

@@ -14,82 +14,15 @@
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
-import json
 import logging
-import time
-from datetime import datetime
-from io import BytesIO
-from typing import Any, Dict, Optional
 
-from flask_babel import lazy_gettext as _
 from sqlalchemy.orm import Session
 
-from superset.connectors.sqla.models import SqlaTable, SqlMetric, TableColumn
-from superset.exceptions import DashboardImportException
 from superset.models.dashboard import Dashboard
-from superset.models.slice import Slice
 
 logger = logging.getLogger(__name__)
 
 
-def decode_dashboards(  # pylint: disable=too-many-return-statements
-    o: Dict[str, Any]
-) -> Any:
-    """
-    Function to be passed into json.loads obj_hook parameter
-    Recreates the dashboard object from a json representation.
-    """
-    from superset.connectors.druid.models import (
-        DruidCluster,
-        DruidColumn,
-        DruidDatasource,
-        DruidMetric,
-    )
-
-    if "__Dashboard__" in o:
-        return Dashboard(**o["__Dashboard__"])
-    if "__Slice__" in o:
-        return Slice(**o["__Slice__"])
-    if "__TableColumn__" in o:
-        return TableColumn(**o["__TableColumn__"])
-    if "__SqlaTable__" in o:
-        return SqlaTable(**o["__SqlaTable__"])
-    if "__SqlMetric__" in o:
-        return SqlMetric(**o["__SqlMetric__"])
-    if "__DruidCluster__" in o:
-        return DruidCluster(**o["__DruidCluster__"])
-    if "__DruidColumn__" in o:
-        return DruidColumn(**o["__DruidColumn__"])
-    if "__DruidDatasource__" in o:
-        return DruidDatasource(**o["__DruidDatasource__"])
-    if "__DruidMetric__" in o:
-        return DruidMetric(**o["__DruidMetric__"])
-    if "__datetime__" in o:
-        return datetime.strptime(o["__datetime__"], "%Y-%m-%dT%H:%M:%S")
-
-    return o
-
-
-def import_dashboards(
-    session: Session,
-    data_stream: BytesIO,
-    database_id: Optional[int] = None,
-    import_time: Optional[int] = None,
-) -> None:
-    """Imports dashboards from a stream to databases"""
-    current_tt = int(time.time())
-    import_time = current_tt if import_time is None else import_time
-    data = json.loads(data_stream.read(), object_hook=decode_dashboards)
-    if not data:
-        raise DashboardImportException(_("No data in file"))
-    for table in data["datasources"]:
-        type(table).import_obj(table, database_id, import_time=import_time)
-    session.commit()
-    for dashboard in data["dashboards"]:
-        Dashboard.import_obj(dashboard, import_time=import_time)
-    session.commit()
-
-
 def export_dashboards(session: Session) -> str:
     """Returns all dashboards metadata as a json dump"""
     logger.info("Starting export")