Allow pre-/post-processing of arguments repr for logging. Fix #5

.coveragerc

@@ -2,4 +2,14 @@
 source =
     logwrap
 omit =
-    test/*
+    test/*
+[report]
+exclude_lines =
+    # Have to re-enable the standard pragma
+    pragma: no cover
+
+    # Don't complain about missing debug-only code:
+    def __repr__
+
+    # Don't complain if non-runnable code isn't run:
+    if __name__ == .__main__.:

CHANGELOG.rst

@@ -4,8 +4,9 @@ Version 3.3.0
 -------------
 * Type hints and stubs
 * PEP0518
-* Deprecation of *args for logwrap
-* Fix empty *args and **kwargs
+* Deprecation of `*args` for logwrap
+* Fix empty `*args` and `**kwargs`
+* allow override for arguments repr processing (pre- and post-processing)
 
 Version 3.2.0
 -------------

README.rst

@@ -187,6 +187,11 @@ Example construction and read from test:
 
 On object change, variable types is validated.
 
+In special cases, when special processing required for parameters logging (hide or change parameters in log),
+it can be done by override `pre_process_param` and `post_process_param`.
+
+See API documentation for details.
+
 
 pretty_repr
 -----------

doc/source/logwrap.rst

@@ -47,7 +47,35 @@ API: Decorators: `LogWrap` class and `logwrap` function.
         :type log_result_obj: bool
 
         .. versionchanged:: 3.3.0 Extract func from log and do not use Union.
-        .. versionchanged:: 3.3.0 Deprecation of *args
+        .. versionchanged:: 3.3.0 Deprecation of `*args`
+
+    .. py:method:: pre_process_param(self, arg)
+
+        Process parameter for the future logging.
+
+        :param arg: bound parameter
+        :type arg: BoundParameter
+        :return: value, value override for logging or None if argument should not be logged.
+        :rtype: typing.Union[BoundParameter, typing.Tuple[BoundParameter, typing.Any], None]
+
+        Override this method if some modifications required for parameter value before logging
+
+        .. versionadded:: 3.3.0
+
+    .. py:method:: post_process_param(self, arg, arg_repr)
+
+        Process parameter for the future logging.
+
+        :param arg: bound parameter
+        :type arg: BoundParameter
+        :param arg_repr: repr for value
+        :type arg_repr: six.text_type
+        :return: processed repr for value
+        :rtype: six.text_type
+
+        Override this method if some modifications required for result of repr() over parameter
+
+        .. versionadded:: 3.3.0
 
     .. note:: Attributes/properties names the same as argument names and changes
               the same fields.
@@ -76,3 +104,104 @@ API: Decorators: `LogWrap` class and `logwrap` function.
 
         :returns: Decorated function. On python 3.3+ awaitable is supported.
         :rtype: typing.Union[typing.Callable, typing.Awaitable]
+
+
+.. py:class:: BoundParameter(object)
+
+    Parameter-like object store BOUND with value parameter.
+
+    .. versionadded:: 3.3.0
+
+    .. py:method:: __init__(self, parameter, value=Parameter.empty)
+
+        Parameter-like object store BOUND with value parameter.
+
+        :param parameter: parameter from signature
+        :type parameter: ``inspect.Parameter``
+        :param value: parameter real value
+        :type value: typing.Any
+        :raises ValueError: No default value and no value
+
+    .. py:attribute:: POSITIONAL_ONLY
+
+        ``enum.IntEnum``
+        Parameter.POSITIONAL_ONLY
+
+    .. py:attribute:: POSITIONAL_OR_KEYWORD
+
+        ``enum.IntEnum``
+        Parameter.POSITIONAL_OR_KEYWORD
+
+    .. py:attribute:: VAR_POSITIONAL
+
+        ``enum.IntEnum``
+        Parameter.VAR_POSITIONAL
+
+    .. py:attribute:: KEYWORD_ONLY
+
+        ``enum.IntEnum``
+        Parameter.KEYWORD_ONLY
+
+    .. py:attribute:: VAR_KEYWORD
+
+        ``enum.IntEnum``
+        Parameter.VAR_KEYWORD
+
+    .. py:attribute:: empty
+
+        ``typing.Type``
+        Parameter.empty
+
+    .. py:attribute:: parameter
+
+        Parameter object.
+
+        :rtype: inspect.Parameter
+
+    .. py:attribute:: name
+
+        Parameter name.
+
+        :rtype: typing.Union[None, str]
+
+    .. py:attribute:: default
+
+        Parameter default value.
+
+        :rtype: typing.Any
+
+    .. py:attribute:: annotation
+
+        Parameter annotation.
+
+        :rtype: typing.Union[Parameter.empty, str]
+
+    .. py:attribute:: kind
+
+        Parameter kind.
+
+        :rtype: enum.IntEnum
+
+    .. py:attribute:: value
+
+        Parameter value.
+
+        :rtype: typing.Any
+
+    .. py:method:: __hash__(self)
+
+        Block hashing.
+
+        :raises TypeError: Not hashable.
+
+
+.. py:function:: bind_args_kwargs(sig, *args, **kwargs)
+
+    Bind `*args` and `**kwargs` to signature and get Bound Parameters.
+
+    :param sig: source signature
+    :type sig: inspect.Signature
+    :return: Iterator for bound parameters with all information about it
+    :rtype: typing.Iterator[BoundParameter]
+
+    .. versionadded:: 3.3.0

logwrap/__init__.py

@@ -33,6 +33,7 @@
     pretty_repr,
     pretty_str
 )
+from ._log_wrap_shared import BoundParameter, bind_args_kwargs
 
 PY3 = sys.version_info[:2] > (3, 0)  # type: bool
 
@@ -50,7 +51,9 @@
     'PrettyRepr',
     'PrettyStr',
     'pretty_repr',
-    'pretty_str'
+    'pretty_str',
+    'BoundParameter',
+    'bind_args_kwargs'
 )
 
 __version__ = '3.2.2'

logwrap/_log_wrap2.py

@@ -56,17 +56,10 @@ def old_spec(
     # pylint: enable=unused-argument
 
     sig = funcsigs.signature(old_spec)  # type: funcsigs.Signature
-    parameters = tuple(sig.parameters.values())  # type: typing.Tuple[funcsigs.Parameter, ...]
-
-    real_parameters = {
-        parameter.name: parameter.default for parameter in parameters
-    }  # type: typing.Dict[str, typing.Any]
-
-    bound = sig.bind(*args, **kwargs).arguments
 
     final_kwargs = {
-        key: bound.get(key, real_parameters[key])
-        for key in real_parameters
+        parameter.name: parameter.value
+        for parameter in _log_wrap_shared.bind_args_kwargs(sig, *args, **kwargs)
     }  # type: typing.Dict[str, typing.Any]
 
     return final_kwargs

logwrap/_log_wrap2.pyi

@@ -3,6 +3,9 @@ import typing
 from . import _log_wrap_shared
 
 class LogWrap(_log_wrap_shared.BaseLogWrap):
+
+    __slots__ = ()
+
     def __init__(
         self,
         func: typing.Optional[typing.Callable]=None,

logwrap/_log_wrap3.py

@@ -57,17 +57,10 @@ def old_spec(
     # pylint: enable=unused-argument
 
     sig = inspect.signature(old_spec)  # type: inspect.Signature
-    parameters = tuple(sig.parameters.values())  # type: typing.Tuple[inspect.Parameter, ...]
-
-    real_parameters = {
-        parameter.name: parameter.default for parameter in parameters
-    }  # type: typing.Dict[str, typing.Any]
-
-    bound = sig.bind(*args, **kwargs).arguments
 
     final_kwargs = {
-        key: bound.get(key, real_parameters[key])
-        for key in real_parameters
+        parameter.name: parameter.value
+        for parameter in _log_wrap_shared.bind_args_kwargs(sig, *args, **kwargs)
     }  # type: typing.Dict[str, typing.Any]
 
     return final_kwargs

logwrap/_log_wrap3.pyi

@@ -3,6 +3,9 @@ import typing
 from . import _log_wrap_shared
 
 class LogWrap(_log_wrap_shared.BaseLogWrap):
+
+    __slots__ = ()
+
     def __init__(
         self,
         func: typing.Optional[typing.Callable]=None,