Add DataExctractedEvent, which is thrown after data and errors are ex…

…tracted from widgets.

CHANGES.txt

@@ -5,7 +5,8 @@ CHANGES
 3.2.1 (unreleased)
 ------------------
 
-- Nothing changed yet.
+- Add DataExctractedEvent, which is thrown after data and errors are extracted
+  from widgets.
 
 
 3.2.0 (2014-03-18)

src/z3c/form/events.py

@@ -0,0 +1,10 @@
+from z3c.form.interfaces import IDataExtractedEvent
+from zope.interface import implementer
+
+
+@implementer(IDataExtractedEvent)
+class DataExctractedEvent(object):
+    def __init__(self, data, errors, form):
+        self.data = data
+        self.errors = errors
+        self.form = form

src/z3c/form/form.py

@@ -27,6 +27,7 @@
 from zope.schema.fieldproperty import FieldProperty
 
 from z3c.form import button, field, interfaces, util
+from z3c.form.events import DataExctractedEvent
 from z3c.form.i18n import MessageFactory as _
 
 
@@ -98,7 +99,7 @@ def handleActionError(event):
 
 
 @zope.interface.implementer(interfaces.IForm,
-                              interfaces.IFieldsForm)
+                            interfaces.IFieldsForm)
 class BaseForm(browser.BrowserPage):
     """A base form."""
 
@@ -143,7 +144,9 @@ def extractData(self, setErrors=True):
         '''See interfaces.IForm'''
         self.widgets.setErrors = setErrors
         self.widgets.ignoreRequiredOnExtract = self.ignoreRequiredOnExtract
-        return self.widgets.extract()
+        data, errors = self.widgets.extract()
+        zope.event.notify(DataExctractedEvent(data, errors, self))
+        return data, errors
 
     def update(self):
         '''See interfaces.IForm'''

src/z3c/form/form.txt

@@ -407,6 +407,18 @@ Let's go back to a normal status to continue the test.
 
   >>> request.response.setStatus(200)
 
+
+Registering a custom event handler for the DataExctractedEvent
+--------------------------------------------------------------
+
+  >>> data_extracted_eventlog = []
+  >>> from z3c.form.events import DataExctractedEvent
+  >>> @zope.component.adapter(DataExctractedEvent)
+  ... def data_extracted_logger(event):
+  ...     data_extracted_eventlog.append(event)
+  >>> zope.component.provideHandler(data_extracted_logger)
+
+
 Submitting an add form successfully
 -----------------------------------
 
@@ -442,6 +454,20 @@ the form with the "Add" button, the person should be added to the root folder:
   20
 
 
+Check, if DataExctractedEvent was thrown
+-----------------------------------------
+
+  >>> event = data_extracted_eventlog[0]
+  >>> 'name' in event.data
+  True
+
+  >>> event.errors
+  ()
+
+  >>> event.form
+  <PersonAddForm object at ...
+
+
 Submitting an add form with invalid data
 ----------------------------------------
 
@@ -468,6 +494,20 @@ message:
   >>> addForm.widgets['name'].error
   <ErrorViewSnippet for RequiredMissing>
 
+
+Check, if event was thrown:
+
+  >>> event = data_extracted_eventlog[-1]
+  >>> 'id' in event.data
+  True
+
+  >>> event.errors
+  (<ErrorViewSnippet for RequiredMissing>,)
+
+  >>> event.form
+  <PersonAddForm object at ...
+
+
 Let's now render the form:
 
   >>> addTemplate(addForm)

src/z3c/form/group.py

@@ -1,4 +1,4 @@
-##############################################################################
+ #########################################################################
 #
 # Copyright (c) 2007 Zope Foundation and Contributors.
 # All Rights Reserved.
@@ -16,10 +16,13 @@
 $Id$
 """
 __docformat__ = "reStructuredText"
-import zope.component
 
 from z3c.form import form, interfaces
 from zope.interface import implementer
+from z3c.form.events import DataExctractedEvent
+
+import zope.component
+import zope.event
 
 
 @implementer(interfaces.IGroup)
@@ -70,11 +73,11 @@ def extractData(self, setErrors=True):
                     errors += groupErrors
                 else:
                     errors = groupErrors
+        zope.event.notify(DataExctractedEvent(data, errors, self))
         return data, errors
 
     def applyChanges(self, data):
         '''See interfaces.IEditForm'''
-        descriptions = []
         content = self.getContent()
         changed = form.applyChanges(self, content, data)
         for group in self.groups:
@@ -101,6 +104,7 @@ def extractData(self, setErrors=True):
                     errors += groupErrors
                 else:
                     errors = groupErrors
+        zope.event.notify(DataExctractedEvent(data, errors, self))
         return data, errors
 
     def applyChanges(self, data):
@@ -118,8 +122,8 @@ def applyChanges(self, data):
                     zope.lifecycleevent.Attributes(interface, *names))
             # Send out a detailed object-modified event
             zope.event.notify(
-                zope.lifecycleevent.ObjectModifiedEvent(content,
-                    *descriptions))
+                zope.lifecycleevent.ObjectModifiedEvent(
+                    content, *descriptions))
 
         return changed
 

src/z3c/form/group.txt

@@ -174,6 +174,18 @@ We can now render the form:
     </body>
   </html>
 
+
+Registering a custom event handler for the DataExctractedEvent
+--------------------------------------------------------------
+
+  >>> data_extracted_eventlog = []
+  >>> from z3c.form.events import DataExctractedEvent
+  >>> @zope.component.adapter(DataExctractedEvent)
+  ... def data_extracted_logger(event):
+  ...     data_extracted_eventlog.append(event)
+  >>> zope.component.provideHandler(data_extracted_logger)
+
+
 Let's now submit the form, but forgetting to enter the address:
 
   >>> request = testing.TestRequest(form={
@@ -199,8 +211,16 @@ Let's now submit the form, but forgetting to enter the address:
   </ul>
 
 As you can see, the template is clever enough to just report the errors at the
-top of the form, but still report the actual problem within the group. So what
-happens, if errors happen inside and outside a group?
+top of the form, but still report the actual problem within the group.
+
+
+Check, if DataExctractedEvent was thrown:
+
+  >>> len(data_extracted_eventlog) > 0
+  True
+
+
+So what happens, if errors happen inside and outside a group?
 
   >>> request = testing.TestRequest(form={
   ...     'form.widgets.firstName': u'Stephan',

src/z3c/form/interfaces.py

@@ -1116,6 +1116,11 @@ class IWidgetEvent(zope.interface.Interface):
         description=_('The widget for which the event was created.'),
         schema=IWidget)
 
+
 class IAfterWidgetUpdateEvent(IWidgetEvent):
     """An event sent out after the widget was updated."""
 
+
+class IDataExtractedEvent(zope.interface.Interface):
+    """Event thrown after data and errors are extracted from widgets.
+    """

src/z3c/form/tests/test_doc.py

@@ -17,7 +17,6 @@
 import itertools
 import re
 import unittest
-
 from zope.testing import renormalizing
 
 from z3c.form import testing