Auto-transfer infos

See the docstring for Component.create_connector for details on how it works.

I think this is a nice usability enhancement. The TimeTrigger component nicely shows how it can simplify the code for transferring metadata. Although it is still relatively complicated how the rules are constructed there, as the component is flexible regarding in which direction to transfer/where to take from. But all the complicated stuff in _connect is automated.

Fixes #73 (closed)

src/finam/tools/__init__.py

@@ -37,9 +37,11 @@ Connect helper
    :toctree: generated
 
     ConnectHelper
+    FromInput
+    FromOutput
+    FromValue
 """
-from . import connect_helper
-from .connect_helper import ConnectHelper
+from .connect_helper import ConnectHelper, FromInput, FromOutput, FromValue
 from .cwd_helper import execute_in_cwd, set_directory
 from .enum_helper import get_enum_value
 from .log_helper import (
@@ -50,8 +52,7 @@ from .log_helper import (
     is_loggable,
 )
 
-__all__ = ["connect_helper"]
-__all__ += ["execute_in_cwd", "set_directory"]
+__all__ = ["execute_in_cwd", "set_directory"]
 __all__ += ["get_enum_value"]
 __all__ += [
     "ErrorLogger",
@@ -60,3 +61,4 @@ __all__ += [
     "LogStdOutStdErr",
     "LogCStdOutStdErr",
 ]
+__all__ += ["ConnectHelper", "FromInput", "FromOutput", "FromValue"]