add quota support for number of fields

extra/modules/boforms.ptl

@@ -45,6 +45,8 @@ from wcs.admin.fields import FieldWidget, FieldDefPage, FieldsDirectory
 from bodiffusion import DiffusionDirectory
 from boresults import FormResultDirectory
 
+import quota
+
 class CustomFieldDefPage(FieldDefPage):
     section = 'forms/'
     wsf_support = False
@@ -53,6 +55,8 @@ class CustomFieldDefPage(FieldDefPage):
         html_top('forms/%s' % self.objectdef.id, *args, **kwargs)
 
     def duplicate(self):
+        if not quota.may_add_a_new_field(self.objectdef):
+            raise quota.QuotaExceeded()
         t = FieldDefPage.duplicate(self)
         if get_response().status_code == 302:
             return redirect('..')
@@ -198,6 +202,12 @@ class FormDirectory(FieldsDirectory):
 
         return form
 
+    def new(self):
+        if quota.may_add_a_new_field(self.objectdef):
+            return super(FormDirectory, self).new()
+        else:
+            raise quota.QuotaExceeded()
+
     def index_top [html] (self):
         '<ul id="main-actions">'
         if self.objectdef.asec_status == 'soon-available':
@@ -271,7 +281,12 @@ class FormDirectory(FieldsDirectory):
                     '<a href="clean" rel="popup">%s</a>' % _('Remove Them')
                     '</p>'
 
-        super(FormDirectory, self).get_new_field_form(page_no)
+        if quota.may_add_a_new_field(self.objectdef):
+            super(FormDirectory, self).get_new_field_form(page_no)
+        else:
+            '<p>'
+            _('This questionnaire has reached its number of questions quota.')
+            '</p>'
 
     def clean [html] (self):
         form = Form(enctype='multipart/form-data')

extra/modules/quota.py

@@ -21,6 +21,7 @@ from quixote.errors import AccessError
 
 from qommon import template
 
+from wcs.fields import WidgetField
 from wcs.formdef import FormDef
 
 class QuotaExceeded(AccessError):
@@ -40,3 +41,21 @@ def may_add_a_new_form():
         return True
     return (FormDef.count() < max_forms)
 
+
+def get_max_number_of_fields():
+    t = get_request().get_header('QuotaFields')
+    if not t:
+        return None
+    return int(t)
+
+def may_add_a_new_field(formdef):
+    max_fields = get_max_number_of_fields()
+    if not max_fields:
+        return True
+    fields_count = 0
+    for field in formdef.fields:
+        # only count data fields, not presentation fields (pages, titles, etc.)
+        if isinstance(field, WidgetField):
+            fields_count += 1
+    return (fields_count < max_fields)
+