gustavz · December 8, 2022 11:43 · Dec 8, 2022 · Dec 8, 2022 · Dec 8, 2022 · Dec 8, 2022
diff --git a/gistfile1.py → data_class_with_decision_log.py b/gistfile1.py → data_class_with_decision_log.py
diff --git a/gistfile1.py b/gistfile1.py
@@ -71,12 +71,6 @@ def __setattr__(self, name, value):
     @property
     def _keys(self):
         return {k.name:k for k in self._converter.keys}
-
-    def _validate(self, data):
-        keys = set(data.keys())
-        if not keys.issubset(self._fields):
-            wrong_keys = keys - self._fields
-            raise ValueError(f'invalid parameters: {wrong_keys}')
 
     @classmethod
     def from_dict(cls, data):

diff --git a/gistfile1.py b/gistfile1.py
@@ -56,10 +56,11 @@ def __init__(self, **kwargs):
 
     def _set_init_kwargs(self, kwargs):
         for key, value in kwargs.items():
-            # We only log attributes defined in _converter 
-            # and we don't log default values
-            if key in self._keys and value != self._keys[key].default:
-                reason = self._logger.generate_reason('initial user input')
+            if key in self._keys:
+                reason = 'initial user input'
+                if value == self._keys[key].default:
+                    reason = 'default value'
+                reason = self._logger.generate_reason(reason)
                 value = value, reason
             setattr(self, key, value)
 
@@ -70,6 +71,12 @@ def __setattr__(self, name, value):
     @property
     def _keys(self):
         return {k.name:k for k in self._converter.keys}
+
+    def _validate(self, data):
+        keys = set(data.keys())
+        if not keys.issubset(self._fields):
+            wrong_keys = keys - self._fields
+            raise ValueError(f'invalid parameters: {wrong_keys}')
 
     @classmethod
     def from_dict(cls, data):

diff --git a/gistfile1.txt → gistfile1.py b/gistfile1.txt → gistfile1.py
diff --git a/gistfile1.txt b/gistfile1.txt
@@ -0,0 +1,90 @@
+import trafaret as t
+
+class DecisionLog:
+    def __init__(self, reason_key=''):
+        self.init()
+        self._reason_key = reason_key
+        self._len_reason_key = len(reason_key)
+
+    def init(self):
+        self.logs = []
+
+    def log(self, text):
+        self.logs.append(text)
+
+    def _read_reason_from_value(self, value):
+        reason = None
+        if(
+            isinstance(value, tuple)
+            and len(value) == 2
+            and isinstance(value[1], str) 
+            and len(value[1]) > self._len_reason_key
+            and value[1][:self._len_reason_key] == self._reason_key
+        ):
+            reason = value[1][self._len_reason_key:]
+            value = value[0]
+        return value, reason
+
+    def _generate_setattr_text(self, name, value, reason):
+        text = f'Setting {name} to {value}'
+        if reason: text += f' because {reason}'
+        return text
+
+    def log_setattr_with_reason(self, name, value):
+        value, reason = self._read_reason_from_value(value)
+        text = self._generate_setattr_text(name, value, reason)
+        self.log(text)
+        return value
+
+    def generate_reason(self, value):
+        return self._reason_key + value
+
+    def to_string(self):
+        for log in self.logs:
+            print(log)
+        return '\n'.join(self.logs)
+
+
+class BaseDataWithDecisionLog:
+    _converter = t.Dict()
+    _logger = DecisionLog(reason_key='r:')
+
+    def __init__(self, **kwargs):
+        self._logger.init()
+        kwargs = self._converter.check_and_return(kwargs)
+        self._set_init_kwargs(kwargs)
+
+    def _set_init_kwargs(self, kwargs):
+        for key, value in kwargs.items():
+            # We only log attributes defined in _converter 
+            # and we don't log default values
+            if key in self._keys and value != self._keys[key].default:
+                reason = self._logger.generate_reason('initial user input')
+                value = value, reason
+            setattr(self, key, value)
+
+    def __setattr__(self, name, value):
+        value = self._logger.log_setattr_with_reason(name, value)
+        super().__setattr__(name, value)
+
+    @property
+    def _keys(self):
+        return {k.name:k for k in self._converter.keys}
+
+    @classmethod
+    def from_dict(cls, data):
+        return cls(**data)
+
+    def to_dict(self):
+        return {k:getattr(self, k) for k in self._keys}
+
+    def get_log(self):
+        return self._logger.to_string()
+
+class MyDataClass(BaseDataWithDecisionLog):
+    _converter = t.Dict({
+        t.Key('var1', optional=True, default=None): t.Or(t.Int, t.Null),
+        t.Key('var2', optional=True, default=None): t.Or(t.Int, t.Null),
+        t.Key('var3', optional=True, default=None): t.Or(t.Int, t.Null),
+        t.Key('var4', optional=True, default=None): t.Or(t.Int, t.Null),
+    })