BI-4968: use a default clickhouse user with an empty username field

lib/dl_connector_clickhouse/dl_connector_clickhouse/api/api_schema/connection.py

@@ -1,6 +1,9 @@
 from __future__ import annotations
 
+from marshmallow import fields as ma_fields
+
 from dl_api_connector.api_schema.connection_base import ConnectionMetaMixin
+from dl_api_connector.api_schema.connection_base_fields import secret_string_field
 from dl_api_connector.api_schema.connection_mixins import (
     DataExportForbiddenMixin,
     RawSQLLevelMixin,
@@ -18,6 +21,14 @@ class ClickHouseConnectionSchema(
     TARGET_CLS = ConnectionClickhouse
     ALLOW_MULTI_HOST = True
 
+    username = ma_fields.String(attribute="data.username", allow_none=True, bi_extra=FieldExtra(editable=True))
+    password = secret_string_field(
+        attribute="data.password",
+        required=False,
+        allow_none=True,
+        bi_extra=FieldExtra(editable=True),
+    )
+
     secure = core_ma_fields.OnOffField(attribute="data.secure", bi_extra=FieldExtra(editable=True))
     ssl_ca = core_ma_fields.Base64StringField(
         attribute="data.ssl_ca",

lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse/constants.py

@@ -3,3 +3,5 @@
 
 SOURCE_TYPE_CH_TABLE = DataSourceType.declare("CH_TABLE")
 SOURCE_TYPE_CH_SUBSELECT = DataSourceType.declare("CH_SUBSELECT")
+
+DEFAULT_CLICKHOUSE_USER = "default"

lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse/testing/connection.py

@@ -16,8 +16,8 @@ def make_clickhouse_saved_connection(
     db_name: Optional[str],
     host: str,
     port: Optional[int],
-    username: Optional[str],
-    password: Optional[str],
+    username: Optional[str] = None,
+    password: Optional[str] = None,
     raw_sql_level: RawSQLLevel = RawSQLLevel.off,
     secure: bool = False,
     ssl_ca: Optional[str] = None,

lib/dl_connector_clickhouse/dl_connector_clickhouse/core/clickhouse/us_connection.py

@@ -6,9 +6,11 @@
 from dl_i18n.localizer_base import Localizer
 
 from dl_connector_clickhouse.core.clickhouse.constants import (
+    DEFAULT_CLICKHOUSE_USER,
     SOURCE_TYPE_CH_SUBSELECT,
     SOURCE_TYPE_CH_TABLE,
 )
+from dl_connector_clickhouse.core.clickhouse_base.dto import ClickHouseConnDTO
 from dl_connector_clickhouse.core.clickhouse_base.us_connection import ConnectionClickhouseBase
 
 
@@ -27,6 +29,13 @@ class ConnectionClickhouse(ConnectionClickhouseBase):
     def get_data_source_template_templates(self, localizer: Localizer) -> list[DataSourceTemplate]:
         return self._make_subselect_templates(source_type=SOURCE_TYPE_CH_SUBSELECT, localizer=localizer)
 
+    def get_conn_dto(self) -> ClickHouseConnDTO:
+        base_dto = super().get_conn_dto()
+        return base_dto.clone(
+            username=base_dto.username or DEFAULT_CLICKHOUSE_USER,
+            password=base_dto.password or "",
+        )
+
     @property
     def allow_public_usage(self) -> bool:
         return True

lib/dl_connector_clickhouse/dl_connector_clickhouse_tests/db/api/base.py

@@ -35,6 +35,16 @@ def connection_params(self) -> dict:
         )
 
 
+class ClickHouseConnectionDefaultUserTestBase(ClickHouseConnectionTestBase):
+    @pytest.fixture(scope="class")
+    def connection_params(self) -> dict:
+        return dict(
+            db_name=CoreConnectionSettings.DB_NAME,
+            host=CoreConnectionSettings.HOST,
+            port=CoreConnectionSettings.PORT,
+        )
+
+
 class ClickHouseDashSQLConnectionTest(ClickHouseConnectionTestBase):
     raw_sql_level = RawSQLLevel.dashsql
 

lib/dl_connector_clickhouse/dl_connector_clickhouse_tests/db/api/test_connection.py

@@ -1,7 +1,14 @@
 from dl_api_lib_testing.connector.connection_suite import DefaultConnectorConnectionTestSuite
 
-from dl_connector_clickhouse_tests.db.api.base import ClickHouseConnectionTestBase
+from dl_connector_clickhouse_tests.db.api.base import (
+    ClickHouseConnectionDefaultUserTestBase,
+    ClickHouseConnectionTestBase,
+)
 
 
 class TestClickHouseConnection(ClickHouseConnectionTestBase, DefaultConnectorConnectionTestSuite):
     pass
+
+
+class TestClickHouseDefaultUserConnection(ClickHouseConnectionDefaultUserTestBase, DefaultConnectorConnectionTestSuite):
+    pass

lib/dl_connector_clickhouse/dl_connector_clickhouse_tests/db/core/base.py

@@ -58,6 +58,16 @@ def saved_connection(
         return conn
 
 
+class BaseClickHouseDefaultUserTestClass(BaseClickHouseTestClass):
+    @pytest.fixture(scope="function")
+    def connection_creation_params(self) -> dict:
+        return dict(
+            db_name=test_config.CoreConnectionSettings.DB_NAME,
+            host=test_config.CoreConnectionSettings.HOST,
+            port=test_config.CoreConnectionSettings.PORT,
+        )
+
+
 class BaseSslClickHouseTestClass(BaseClickHouseTestClass):
     @pytest.fixture(autouse=True)
     def clear_ssl_folder(self):

lib/dl_connector_clickhouse/dl_connector_clickhouse_tests/db/core/test_connection.py

@@ -7,8 +7,10 @@
 from dl_core.us_connection_base import DataSourceTemplate
 from dl_core_testing.testcases.connection import DefaultConnectionTestClass
 
+from dl_connector_clickhouse.core.clickhouse.constants import DEFAULT_CLICKHOUSE_USER
 from dl_connector_clickhouse.core.clickhouse.us_connection import ConnectionClickhouse
 from dl_connector_clickhouse_tests.db.core.base import (
+    BaseClickHouseDefaultUserTestClass,
     BaseClickHouseTestClass,
     BaseSslClickHouseTestClass,
 )
@@ -42,6 +44,15 @@ def check_data_source_templates(
         assert "system" not in tmpl_db_names
 
 
+class TestClickHouseDefaultUserConnection(BaseClickHouseDefaultUserTestClass, TestClickHouseConnection):
+    def check_saved_connection(self, conn: ConnectionClickhouse, params: dict) -> None:
+        assert conn.uuid is not None
+        assert conn.data.db_name == params["db_name"]
+        assert conn.data.username is None
+        assert conn.data.secure is False
+        assert conn.data.ssl_ca is None
+
+
 @pytest.mark.skipif(os.environ.get("WE_ARE_IN_CI"), reason="can't use localhost")
 class TestSslClickHouseConnection(
     BaseSslClickHouseTestClass,

lib/dl_core/dl_core/connection_models/dto_defs.py

@@ -1,16 +1,20 @@
 from __future__ import annotations
 
 from typing import (
+    Any,
     ClassVar,
-    List,
     Optional,
+    TypeVar,
 )
 
 import attr
 
 from dl_constants.enums import ConnectionType
 
 
+_CONN_DTO_TV = TypeVar("_CONN_DTO_TV")
+
+
 @attr.s(frozen=True)
 class ConnDTO:
     conn_type: ClassVar[ConnectionType]
@@ -22,6 +26,9 @@ def conn_reporting_data(self) -> dict:
             connection_id=self.conn_id,
         )
 
+    def clone(self: _CONN_DTO_TV, **kwargs: Any) -> _CONN_DTO_TV:
+        return attr.evolve(self, **kwargs)
+
 
 @attr.s(frozen=True)
 class DefaultSQLDTO(ConnDTO):  # noqa
@@ -32,7 +39,7 @@ class DefaultSQLDTO(ConnDTO):  # noqa
     username: str = attr.ib(kw_only=True)
     password: str = attr.ib(repr=False, kw_only=True)
 
-    def get_all_hosts(self) -> List[str]:
+    def get_all_hosts(self) -> list[str]:
         return list(self.multihosts) if self.multihosts else [self.host] if self.host else []
 
     def conn_reporting_data(self) -> dict: