Implement dttm config

superset/config.py

@@ -352,6 +352,18 @@ def _try_json_readsha(filepath, length):  # pylint: disable=unused-argument
 # }
 TIME_GRAIN_ADDON_FUNCTIONS: Dict[str, Dict[str, str]] = {}
 
+# Default python_date_format and expression for the sql tables dttm columns.
+# It is useful for the use cases when there is a company wide convention.
+# Example:
+# DTTM_CONFIG = {
+#     'ts': {'python_date_format': 'epoch_s'},
+#     'hour_ts': {
+#         'python_date_format': 'epoch_s',
+#         'expression': 'CAST(hour_ts as INTEGER)'
+#     },
+# }
+DTTM_CONFIG: Optional[Dict[str, Dict[str, str]]] = None
+
 # ---------------------------------------------------
 # List of viz_types not allowed in your environment
 # For example: Blacklist pivot table and treemap:

superset/connectors/sqla/views.py

@@ -18,8 +18,9 @@
 """Views used by the SqlAlchemy connector"""
 import logging
 import re
+from collections import defaultdict
 
-from flask import flash, Markup, redirect
+from flask import app, flash, Markup, redirect
 from flask_appbuilder import CompactCRUDMixin, expose
 from flask_appbuilder.actions import action
 from flask_appbuilder.fieldwidgets import Select2Widget
@@ -29,7 +30,7 @@
 from wtforms.ext.sqlalchemy.fields import QuerySelectField
 from wtforms.validators import Regexp
 
-from superset import appbuilder, db, security_manager
+from superset import app as superset_app, appbuilder, db, security_manager
 from superset.connectors.base.views import DatasourceModelView
 from superset.utils import core as utils
 from superset.views.base import (
@@ -44,6 +45,7 @@
 from . import models
 
 logger = logging.getLogger(__name__)
+config = superset_app.config
 
 
 class TableColumnInlineView(CompactCRUDMixin, SupersetModelView):
@@ -359,6 +361,21 @@ def pre_add(self, table):
 
     def post_add(self, table, flash_message=True):
         table.fetch_metadata()
+        dttm_config = config.get("DTTM_CONFIG", {})
+        for col in table.columns:
+            if col.column_name in dttm_config:
+                col.is_dttm = True
+                if not col.expression and "expression" in dttm_config[col.column_name]:
+                    col.expression = dttm_config[col.column_name]["expression"]
+                if (
+                    not col.python_date_format
+                    and "python_date_format" in dttm_config[col.column_name]
+                ):
+                    col.python_date_format = dttm_config[col.column_name][
+                        "python_date_format"
+                    ]
+        db.session.commit()
+
         security_manager.add_permission_view_menu("datasource_access", table.get_perm())
         if table.schema:
             security_manager.add_permission_view_menu(

tests/core_tests.py

@@ -335,6 +335,38 @@ def test_tablemodelview_list(self):
         assert table.name in resp
         assert "/superset/explore/table/{}".format(table.id) in resp
 
+    @mock.patch("superset.connectors.sqla.views.config")
+    def test_tablemodelview_add(self, mock_config):
+        mock_config.get.return_value = {
+            "dttm": {
+                "expression": "test_expression",
+                "python_date_format": "test_python_date_format",
+            },
+            "nonexistant": {
+                "expression": "test_expression_v2",
+                "python_date_format": "python_date_format_v2",
+            },
+        }
+        self.login(username="admin")
+        # assert that /tablemodelview/add responds with 200
+        example_db = utils.get_example_database()
+        resp = self.client.post(
+            "/tablemodelview/add",
+            data=dict(database=example_db.id, table_name="logs"),
+            follow_redirects=True,
+        )
+        self.assertEqual(resp.status_code, 200)
+        added_table = db.session.query(SqlaTable).filter_by(table_name="logs").one()
+
+        assert len(added_table.dttm_cols) == 1
+        dttm_col_name = added_table.dttm_cols[0]
+        assert dttm_col_name == "dttm"
+
+        # Make sure that dttm defaults were propagated.
+        dttm_col = [c for c in added_table.columns if c.column_name == dttm_col_name][0]
+        assert dttm_col.expression == "test_expression"
+        assert dttm_col.python_date_format == "test_python_date_format"
+
     def test_add_slice(self):
         self.login(username="admin")
         # assert that /chart/add responds with 200