Introduce new config fields to filesystem destination configuration

dlt/destinations/impl/filesystem/configuration.py

@@ -1,17 +1,34 @@
 import dataclasses
-from typing import Final, Type, Optional
+from typing import Callable, Dict, Final, Optional, Type, Union
 
 from dlt.common.configuration import configspec, resolve_type
 from dlt.common.destination.reference import (
     CredentialsConfiguration,
     DestinationClientStagingConfiguration,
 )
+
 from dlt.common.storages import FilesystemConfiguration
+from pendulum.datetime import DateTime
+from typing_extensions import TypeAlias
+
+TCurrentDatetimeCallback: TypeAlias = Callable[[], DateTime]
+"""A callback which should return current datetime"""
+
+TDatetimeFormat: TypeAlias = str
+"""Datetime format or formatter callback"""
+
+TLayoutParamCallback: TypeAlias = Callable[[str, str, str, str, str, DateTime], str]
+"""A callback which should return prepared string value the following arguments passed
+`schema name`, `table name`, `load_id`, `file_id`, `extension` and `current_datetime`.
+"""
 
 
 @configspec
 class FilesystemDestinationClientConfiguration(FilesystemConfiguration, DestinationClientStagingConfiguration):  # type: ignore[misc]
     destination_type: Final[str] = dataclasses.field(default="filesystem", init=False, repr=False, compare=False)  # type: ignore
+    current_datetime: Optional[Union[DateTime, TCurrentDatetimeCallback]] = None
+    datetime_format: Optional[TDatetimeFormat] = None
+    extra_placeholders: Optional[Dict[str, Union[str, TLayoutParamCallback]]] = None
 
     @resolve_type("credentials")
     def resolve_credentials_type(self) -> Type[CredentialsConfiguration]:

dlt/destinations/impl/filesystem/factory.py

@@ -1,5 +1,7 @@
 import typing as t
 
+import pendulum
+
 from dlt.destinations.impl.filesystem.configuration import FilesystemDestinationClientConfiguration
 from dlt.destinations.impl.filesystem import capabilities
 from dlt.common.destination import Destination, DestinationCapabilitiesContext
@@ -55,3 +57,13 @@ def __init__(
             environment=environment,
             **kwargs,
         )
+
+    def configuration(
+        self, initial_config: FilesystemDestinationClientConfiguration
+    ) -> FilesystemDestinationClientConfiguration:
+        # If current_datetime is not provided then
+        # we need to make sure we have it one per
+        # filesystem destination instance
+        if not initial_config.current_datetime:
+            initial_config.current_datetime = pendulum.now()
+        return super().configuration(initial_config)