[SIP-29] Add support for row-level security (#8699)

* Support and apply filters.

* Added the UI for row level security, and moved it all under SQLA in order to access the Table model more easily.

* Added a row level security filter documentation entry.

* Accidentally added two new lines to this file.

* Blacked and iSorted, hopefully.  Also, sometimes g.user may not be set.

* Another isort, and handling g not having a user attribute another way.

* Let's try this again #CI tests.

* Adjusted import order for isort; I was sure I'd already done this..

* Row level filters should be wrapped in parentheses in case one contains an OR.

* Oops, did not think that would change Black's formatting.

* Changes as per @mistercrunch.

* RLS filters are now many-to-many with Roles.

* Updated documentation to reflect RLS filters supporting multiple rows.

* Let's see what happens when I set it to the previous revision ID

* Updated from upstream.

* There was a pylint error.

* Added RLS ids to the cache keys; modified documentation; added template processing to RLS filters.

* A new migration was merged in.

* Removed RLS cache key from query_object.

* RLS added to the cache_key from query_context.

* Changes as per @etr2460.

* Updating entry for RLS pull request.

* Another migration to skip.

* Changes as per @serenajiang.

* Blacked.

* Blacked and added some attributes to check for.

* Changed to a manual query as per @mistercrunch.

* Blacked.

* Another migration in the meantime.

* Black wanted some whitespace changes.

* AttributeError: 'AnonymousUserMixin' object has no attribute 'id'.

* Oops, did hasattr backwards.

* Changes as per @mistercrunch.

* Doesn't look like text us required here anymore.

* Changes as per @dpgaspar

* Two RLS tests.

* Row level security is now disabled by default via the feature flag ENABLE_ROW_LEVEL_SECURITY.

* New head to revise.

* Changed the comment.

tests/security_tests.py

@@ -20,11 +20,12 @@ import unittest
 from unittest.mock import Mock, patch
 
 import prison
+from flask import g
 
 import tests.test_app
 from superset import app, appbuilder, db, security_manager, viz
 from superset.connectors.druid.models import DruidCluster, DruidDatasource
-from superset.connectors.sqla.models import SqlaTable
+from superset.connectors.sqla.models import RowLevelSecurityFilter, SqlaTable
 from superset.exceptions import SupersetSecurityException
 from superset.models.core import Database
 from superset.models.slice import Slice
@@ -815,3 +816,71 @@ class SecurityManagerTests(SupersetTestCase):
 
         with self.assertRaises(SupersetSecurityException):
             security_manager.assert_viz_permission(test_viz)
+
+
+class RowLevelSecurityTests(SupersetTestCase):
+    """
+    Testing Row Level Security
+    """
+
+    rls_entry = None
+
+    def setUp(self):
+        session = db.session
+
+        # Create the RowLevelSecurityFilter
+        self.rls_entry = RowLevelSecurityFilter()
+        self.rls_entry.table = (
+            session.query(SqlaTable).filter_by(table_name="birth_names").first()
+        )
+        self.rls_entry.clause = "gender = 'male'"
+        self.rls_entry.roles.append(
+            security_manager.find_role("Gamma")
+        )  # db.session.query(Role).filter_by(name="Gamma").first())
+        db.session.add(self.rls_entry)
+
+        db.session.commit()
+
+    def tearDown(self):
+        session = db.session
+        session.delete(self.rls_entry)
+        session.commit()
+
+    # Do another test to make sure it doesn't alter another query
+    def test_rls_filter_alters_query(self):
+        g.user = self.get_user(
+            username="gamma"
+        )  # self.login() doesn't actually set the user
+        tbl = self.get_table_by_name("birth_names")
+        query_obj = dict(
+            groupby=[],
+            metrics=[],
+            filter=[],
+            is_timeseries=False,
+            columns=["name"],
+            granularity=None,
+            from_dttm=None,
+            to_dttm=None,
+            extras={},
+        )
+        sql = tbl.get_query_str(query_obj)
+        self.assertIn("gender = 'male'", sql)
+
+    def test_rls_filter_doesnt_alter_query(self):
+        g.user = self.get_user(
+            username="admin"
+        )  # self.login() doesn't actually set the user
+        tbl = self.get_table_by_name("birth_names")
+        query_obj = dict(
+            groupby=[],
+            metrics=[],
+            filter=[],
+            is_timeseries=False,
+            columns=["name"],
+            granularity=None,
+            from_dttm=None,
+            to_dttm=None,
+            extras={},
+        )
+        sql = tbl.get_query_str(query_obj)
+        self.assertNotIn("gender = 'male'", sql)