Add field setting hooks for SchemeNode

README.md

@@ -8,6 +8,8 @@
 | :---: |
 
 ## QuickScheme Release Notes
+* 0.2.0
+    * Add before/instead/after field set hooks
 * 0.1.1
     * Add Validators
 * 0.1.0

package.cfg

@@ -1,5 +1,5 @@
 [Package]
-version =  0.1.1pre
+version =  0.2.0
 name = QuickScheme
 description = Quick Way To Define Data Schema and Mapping Data To Objects
 url = https://mlasevich.github.io/QuickScheme/

src/quick_scheme/base_node.py

@@ -46,7 +46,7 @@ def __init__(self, parent=None, identity=None, data=None, **kwargs):
         self._data = None
         self.quick_scheme = ProxyAccess(self)
         self._set_identity(identity)
-        self._set_data(data)
+        self._from_data(data)
         self._is_valid = self._validate(True)
 
     def _root(self):
@@ -126,6 +126,14 @@ def __repr__(self, *_args, **_kwargs):
     def _initialize(self, *args, **kwargs):
         ''' Initialization hook for object - called before the data is set'''
 
+    def _from_data(self, data):
+        ''' Set this parameter from data '''
+        self._set_data(data)
+        self._inflate()
+
+    def _inflate(self):
+        ''' Post Load Inflate Hook '''
+
     def _set_data(self, data):
         ''' Set data for this object '''
         self._data = data

src/quick_scheme/field.py

@@ -65,7 +65,7 @@ def get_data(self):
         value = self.get()
         if isinstance(value, SchemeBaseNode):
             data = value.quick_scheme.get_data()
-            #ident = value.quick_scheme.get_identity()
+            # ident = value.quick_scheme.get_identity()
             # print("** Data for %s - %s is %s (%s)" %
             #      (ident if ident is not None else '*', self.name(), data, type(data)))
 
@@ -87,10 +87,12 @@ def get(self):
     def is_valid(self):
         ''' Check if this field value is valid '''
         if self.node:
-            if self.field.required and not self.is_set:
-                LOG.debug("Field '%s' in '%s' is required but not set",
-                          self.name(), self.node._path_str())
-                return False
+            if not self.is_set:
+                if self.field.required:
+                    LOG.debug("Field '%s' in '%s' is required but not set",
+                              self.name(), self.node._path_str())
+                    return False
+                return True
             return self.field.validate(self)
         return True
 
@@ -127,14 +129,14 @@ def __getattr__(self, item):
 
     @property
     def is_qs_node(self):
-        ''' 
+        '''
         Returns true, if type for this field is a QuickScheme Node (i.e. a child of SchemeBaseNode)
          '''
         return issubclass(self.ftype, SchemeBaseNode)
 
     @property
     def has_default(self):
-        ''' 
+        '''
         Returns True if this field has a default value '''
         default = self._data.get('default', None)
         return default is not None

src/quick_scheme/nodes/__init__.py

@@ -2,4 +2,4 @@
 from .key_based_list import KeyBasedListNode, KeyBasedList
 from .list_of_nodes import ListOfNodes
 from .list_of_references import ListOfReferences
-from .node import SchemeNode
+from quick_scheme.nodes.scheme_node import SchemeNode

src/quick_scheme/nodes/key_based_list.py

@@ -2,7 +2,7 @@
 
 from ..base_node import SchemeBaseNode
 from quick_scheme.field import FieldValue
-from .node import SchemeNode
+from quick_scheme.nodes.scheme_node import SchemeNode
 
 
 class KeyBasedListNode(SchemeNode):

src/quick_scheme/nodes/key_based_list_test.py

@@ -6,7 +6,7 @@
 
 from quick_scheme.field import Field
 from .key_based_list import KeyBasedList, KeyBasedListInst, KeyBasedListNode
-from .node import SchemeNode
+from quick_scheme.nodes.scheme_node import SchemeNode
 
 
 def clean_dict(data):

src/quick_scheme/nodes/node.py → src/quick_scheme/nodes/scheme_node.py

@@ -2,21 +2,22 @@
 Base Node Types
 
 '''
+from email.policy import default
 import logging
 
 from quick_scheme.field import FieldValue
 
 from ..base_node import SchemeBaseNode
 from ..exceptions import QuickSchemeValidationException
 from ..qs_yaml import UnsortableOrderedDict
+from ..utils import Args
 
 
 LOG = logging.getLogger(__name__)
 
 
 class SchemeNode(SchemeBaseNode):
     ''' Basic Node - a dictionary with defined Fields '''
-
     # List of fields
     FIELDS = []
     # Allow undefined fields. if false, throw exception on undefined field
@@ -110,27 +111,56 @@ def _fields(self):
         ''' Get fields '''
         return self._int_get('fields', {})
 
+    def _run_if_present(self, name, default_value=None, args=None):
+        ''' Run method if present '''
+        if args is None:
+            args = Args()
+        if hasattr(self, name):
+            LOG.warning("Found method %s", name)
+            return args.run(getattr(self, name), default)
+        return default_value
+
+    def _set_field_data(self, field, value, extra_data):
+        ''' Internal part of set field data '''
+        indexed_value_holder = self._fields.get(field, None)
+        if indexed_value_holder is not None:
+            _, value_holder = indexed_value_holder
+            value_holder.set(value, parent=self, identity=field)
+            field_exists = True
+        else:
+            field_exists = False
+            if self.ALLOW_UNDEFINED:
+                LOG.warning("M3: adding extra field %s", field)
+                extra_data[field] = value
+            else:
+                raise QuickSchemeValidationException("Invalid field '%s' for '%s'" % (field,
+                                                                                      self._name))
+        return field_exists
+
+    def _init_field(self, field, value, extra_data):
+        ''' Set data for one field. This is the outer call that calls hooks '''
+        args = Args(value, field=field, extra_data=extra_data)
+        value = self._run_if_present('_before_set_%s' % field, value, args)
+        field_exists = False
+        if not self._run_if_present('_do_set_%s' % field, False, args):
+            field_exists = self._set_field_data(field, value, extra_data)
+        return self._run_if_present('_after_set_%s' % field, field_exists, args)
+
     def _set_data(self, data):
         ''' Set data for this object '''
         extra_data = self._get_map_class_instance()
 
-        fields = self._fields
+        keys_set = []
         if isinstance(data, dict):
-            for key, value in data.items():
-                indexed_value_holder = fields.get(key, None)
-                if indexed_value_holder is not None:
-                    _, value_holder = indexed_value_holder
-                    value_holder.set(value, parent=self, identity=key)
-                else:
-                    if self.ALLOW_UNDEFINED:
-                        extra_data[key] = value
-                    else:
-                        raise QuickSchemeValidationException(
-                            "Invalid field '%s' for '%s'" % (key, self._name))
+            for field, value in data.items():
+                keys_set.append(object)
+                self._init_field(field, value, extra_data)
         else:
-            # print("Invalid data type: %s for %s (%s)" %
-            #      (type(data), self.quick_scheme.path_str(), data))
             self._brief_set(data)
+
+        LOG.error("%s fields not set, %s extra fields when setting %s from %s",
+                  len(keys_set), len(extra_data), self._path_str(), data)
+
         self._data = extra_data
 
     def _get_by_id(self, id):

src/quick_scheme/nodes/node_test.py → src/quick_scheme/nodes/scheme_node_test.py

@@ -3,9 +3,10 @@
 import logging
 import unittest
 
-from ..exceptions import QuickSchemeValidationException
 from quick_scheme.field import Field
-from .node import SchemeNode
+from quick_scheme.nodes.scheme_node import SchemeNode
+
+from ..exceptions import QuickSchemeValidationException
 
 
 class MyEmptyNode(SchemeNode):
@@ -39,6 +40,22 @@ class MyOpenNode(MyClosedNode):
         Field('integer_with_default_2', ftype=int, default=2, always=False),
     ]
 
+    def _before_set_b4(self, value, **_):
+        ''' Runs Before b4 is set '''
+        value = "__" + value + "__"
+        return value
+
+    def _after_set_after(self, value, field, extra_data):
+        ''' Runs After 'after' is set '''
+        extra_data['after_%s' % field] = value
+        return True
+
+    def _do_set_override(self, value, field, extra_data):
+        ''' Runs instead setting 'override' '''
+        print("Overriding!")
+        extra_data['instead'] = {field: value}
+        return True
+
 
 class TestSchemeNode(unittest.TestCase):
     '''Field tests'''
@@ -130,6 +147,43 @@ def test_open_node_data(self):
                                                             'integer_no_default': 5,
                                                             'integer_with_default_1': 1})
 
+    def test_open_node_data_hooks_b4(self):
+        ''' Test before_set hook'''
+        node = MyOpenNode(
+            None, data={'id': 'value', 'integer_no_default': 5, 'b4': 'my_before'})
+        self.assertEqual(len(node.quick_scheme.fields),
+                         len(MyClosedNode.FIELDS))
+        self.assertDictEqual(node.quick_scheme.get_data(), {'id': 'value',
+                                                            'name': 'def',
+                                                            'integer_no_default': 5,
+                                                            'integer_with_default_1': 1,
+                                                            'b4': '__my_before__'})
+
+    def test_open_node_data_hooks_after(self):
+        ''' Test after_set hook'''
+        node = MyOpenNode(
+            None, data={'id': 'value', 'integer_no_default': 5, 'after': 'my_after'})
+        self.assertEqual(len(node.quick_scheme.fields),
+                         len(MyClosedNode.FIELDS))
+        self.assertDictEqual(node.quick_scheme.get_data(), {'id': 'value',
+                                                            'name': 'def',
+                                                            'integer_no_default': 5,
+                                                            'integer_with_default_1': 1,
+                                                            'after': 'my_after',
+                                                            'after_after': 'my_after'})
+
+    def test_open_node_data_hooks_instead(self):
+        ''' Test 'on-set' hook '''
+        node = MyOpenNode(
+            None, data={'id': 'value', 'integer_no_default': 5, 'override': 'my_instead'})
+        self.assertEqual(len(node.quick_scheme.fields),
+                         len(MyClosedNode.FIELDS))
+        self.assertDictEqual(node.quick_scheme.get_data(), {'id': 'value',
+                                                            'name': 'def',
+                                                            'integer_no_default': 5,
+                                                            'integer_with_default_1': 1,
+                                                            'instead': {'override': 'my_instead'}})
+
     def test_open_node_extra_data(self):
         ''' Test getting action_desc'''
 

src/quick_scheme/proxy_access_test.py

@@ -4,7 +4,7 @@
 import unittest
 
 from .base_node import ProxyAccess
-from .nodes.node import SchemeNode
+from quick_scheme.nodes.scheme_node import SchemeNode
 
 
 class MyEmptyNode(SchemeNode):

src/quick_scheme/utils.py

@@ -0,0 +1,18 @@
+''' Utilities '''
+import logging
+
+LOG = logging.getLogger(__name__)
+
+
+class Args(object):
+    ''' Argument Holder '''
+
+    def __init__(self, *args, **kwargs):
+        self.args = args
+        self.kwargs = kwargs
+
+    def run(self, function, default=None):
+        ''' Run a runable function'''
+        if callable(function):
+            return function(*self.args, **self.kwargs)
+        return default