Fix: Verify string lengths when creating model objects

pyjeeves/models/abc.py

@@ -11,13 +11,14 @@ from sqlalchemy.exc import OperationalError
 from sqlalchemy.schema import MetaData, Column
 from sqlalchemy.types import Integer
 from sqlalchemy.orm.collections import InstrumentedList
+from sqlalchemy import event
 
 from sqlservice import ModelBase, as_declarative
 
 from pyjeeves import logging
 
 from . import db
-from .ext import InstallValidatorListeners
+from .ext import install_validator_listner
 
 logger = logging.getLogger("PyJeeves." + __name__)
 
@@ -38,7 +39,6 @@ except OperationalError as e:
 class RawBaseModel(ModelBase):
     """ Generalize __init__, __repr__ and to_json
         Based on the models columns , ForetagKod=1"""
-    __sa_instrumentation_manager__ = InstallValidatorListeners
 
     __to_dict_filter__ = []
     __to_dict_only__ = ()
@@ -75,9 +75,10 @@ class RawBaseModel(ModelBase):
             filters
         )
 
-    def _map_columns(self, key):
+    @classmethod
-        if key in self.__column_map__:
+    def _map_columns(cls, key):
-            return self.__column_map__[key]
+        if key in cls.__column_map__:
+            return cls.__column_map__[key]
         return key
 
     def _map_keys(self, data={}):
@@ -185,3 +186,11 @@ class RawBaseModel(ModelBase):
     def delete(self):
         db.raw_session.delete(self)
         db.raw_session.commit()
+
+
+# Apply validators for all string attributes in subclasses of RawBaseModel
+@event.listens_for(RawBaseModel, 'attribute_instrument')
+def receive_attribute_instrument(cls, key, inst):
+    "listen for the 'attribute_instrument' event"
+
+    install_validator_listner(cls, key, inst)

pyjeeves/models/ext.py

@@ -1,5 +1,4 @@
-from sqlalchemy.ext.instrumentation import InstrumentationManager
+
-# from sqlalchemy.orm.interfaces import AttributeExtension
 from sqlalchemy.orm import ColumnProperty
 from sqlalchemy.types import String
 from sqlalchemy import event
@@ -28,18 +27,17 @@ class JeevesDBError(Error):
         self.message = message
 
 
-class InstallValidatorListeners(InstrumentationManager):
+def install_validator_listner(class_, key, inst):
-    def post_configure_attribute(self, class_, key, inst):
+    """Add validators for any attributes that can be validated."""
-        """Add validators for any attributes that can be validated."""
+    prop = inst.prop
-        prop = inst.prop
+    # Only interested in simple columns, not relations
-        # Only interested in simple columns, not relations
+    if isinstance(prop, ColumnProperty) and len(prop.columns) == 1:
-        if isinstance(prop, ColumnProperty) and len(prop.columns) == 1:
+        col = prop.columns[0]
-            col = prop.columns[0]
+        # if we have string column with a length, create a length validator listner
-            # if we have string column with a length, create a length validator listner
+        if isinstance(col.type, String) and col.type.length:
-            if isinstance(col.type, String) and col.type.length:
+            event.listen(
-                event.listen(
+                getattr(class_, key), 'set', LengthValidator(
-                    getattr(class_, key), 'set', LengthValidator(
+                    col.name, col.type.length), retval=True)
-                        col.name, col.type.length), retval=True)
 
 
 class LengthValidator():
@@ -51,5 +49,6 @@ class LengthValidator():
         if len(value) > self.max_length:
             raise ValidationError(
                 "%s.%s: Length %d exceeds allowed %d" % (
-                    state.__class__.__name__, self.col_name, len(value), self.max_length))
+                    state.__class__.__name__, state.__class__._map_columns(self.col_name),
+                    len(value), self.max_length))
         return value