+
−#!/usr/bin/python2.5
+
−#
+
−# Copyright 2008 the Melange authors.
+
−#
+
−# Licensed under the Apache License, Version 2.0 (the "License");
+
−# you may not use this file except in compliance with the License.
+
−# You may obtain a copy of the License at
+
−#
+
−#   http://www.apache.org/licenses/LICENSE-2.0
+
−#
+
−# Unless required by applicable law or agreed to in writing, software
+
−# distributed under the License is distributed on an "AS IS" BASIS,
+
−# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+
−# See the License for the specific language governing permissions and
+
−# limitations under the License.
+
−
+
−"""Helpers used to display various views that are forms.
+
−"""
+
−
+
−__authors__ = [
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−  '"Chen Lunpeng" <forever.clp@gmail.com>',
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−  '"Todd Larsen" <tlarsen@google.com>',
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−  ]
+
−
+
−
+
−from google.appengine.ext.db import djangoforms
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−
+
−from django import forms
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−from django.utils import safestring
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−
+
−
+
−class DbModelForm(djangoforms.ModelForm):
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−  """Subclass of Django ModelForm that fixes some label and help_text issues.
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−
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−  The default behavior of ModelForm is to use the verbose_name in all
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−  lowercase, capitalizing only the first character, as the displayed field
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−  label.  This class uses verbose_name unaltered as the visible field label
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−  instead.
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−
+
−  The Property classes used by the App Engine Datastore do not have a
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−  help_text parameter to their constructor.  In a Model class, a help_text
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−  attribute *can* be added to the property after it is created, but the
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−  help text will not be automatically passed along to the Django ModelForm.
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−  This class detects the presence of a help_text attribute and adds it to
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−  the corresponding form field object.
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−
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−  ugettext_lazy() proxies used for internationalization in the Model will
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−  still work correctly with this new behavior, as long as the original
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−  strings are used as the translation keys.
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−  """
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−
+
−  def __init__(self, *args, **kwargs):
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−    """Fixes label and help_text issues after parent initialization.
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−
+
−    Args:
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−      *args, **kwargs:  passed through to parent __init__() constructor
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−    """
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−    super(DbModelForm, self).__init__(*args, **kwargs)
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−
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−    for field_name in self.fields.iterkeys():
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−      # Since fields can be added only to the ModelForm subclass, check to
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−      # see if the Model has a corresponding field first.
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−      if hasattr(self.Meta.model, field_name):
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−        model_prop = getattr(self.Meta.model, field_name)
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−
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−        # Check if the Model property defined verbose_name, and copy that
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−        # verbatim to the corresponding field label.
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−        if hasattr(model_prop, 'verbose_name'):
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−          self.fields[field_name].label = model_prop.verbose_name
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−
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−        # Check if the Model property added help_text, and copy that verbatim
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−        # to the corresponding field help_text.
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−        if hasattr(model_prop, 'help_text'):
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−          self.fields[field_name].help_text = model_prop.help_text
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−
+
−
+
−class BaseForm(DbModelForm):
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−  """Subclass of DbModelForm that extends as_table HTML output.
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−  
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−  BaseForm has additional class names in HTML tags for label and help text
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−  and those can be used in CSS files for look customization. The way the Form
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−  prints itself also has changed. Help text is displayed in the same row as 
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−  label and input.
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−  """
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−  # TODO(pawel.solyga): Add class names for form errors and required fields.
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−  
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−  DEF_NORMAL_ROW = u'<tr><td class="formfieldlabel">%(label)s</td>' \
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−      '<td>%(errors)s%(field)s%(help_text)s</td></tr>'
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−  DEF_ERROR_ROW = u'<tr><td colspan="2">%s</td></tr>'
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−  DEF_ROW_ENDER = '</td></tr>'
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−  DEF_HELP_TEXT_HTML = u'<td class="formfieldhelptext">%s</td>'
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−  
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−  def __init__(self, *args, **kwargs):
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−    """Parent class initialization.
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−
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−    Args:
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−      *args, **kwargs:  passed through to parent __init__() constructor
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−    """
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−    super(BaseForm, self).__init__(*args, **kwargs)
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−
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−  def as_table(self):
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−    """Returns form rendered as HTML <tr> rows -- with no <table></table>."""
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−    return self._html_output(self.DEF_NORMAL_ROW, 
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−                             self.DEF_ERROR_ROW, 
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−                             self.DEF_ROW_ENDER, 
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−                             self.DEF_HELP_TEXT_HTML, False)
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−
+
−
+
−class SelectQueryArgForm(forms.Form):
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−  """URL query argument change control implemented as a Django form.
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−  """
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−
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−  ONCHANGE_JAVASCRIPT_FMT = '''
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−<script type="text/javascript"> 
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−  function changeArg_%(arg_name)s(item) 
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−  {
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−    var idx=item.selectedIndex;
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−    item.selected=true;
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−    var value=item.value 
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−    var url = location.href 
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−    var reg = /%(arg_name)s=\d+/ 
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−    url = url.replace(reg, "%(arg_name)s="+value) 
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−    if(url.match(reg))
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−      document.location.href = url 
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−   else
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−      document.location.href = "%(page_path)s?%(arg_name)s="+value; 
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−  }
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−</script>
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−'''
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−
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−  def __init__(self, page_path, arg_name, choices, field_name,
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−               *form_args, **form_kwargs):
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−    """
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−    Args:
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−      page_path: (usually request.path)
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−      arg_name: the URL query parameter that determines which choice is
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−        selected in the selection control
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−      choices: list (or tuple) of value/label string two-tuples, for example:
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−        (('10', '10 items per page'), ('25', '25 items per page'))
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−      field_name: name of the selection field in the form
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−      *form_args: positional arguments passed on to the Form base
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−        class __init__()
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−      *form_kwargs: keyword arguments passed on to the Form base
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−        class __init__()
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−    """
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−    super(SelectQueryArgForm, self).__init__(*form_args, **form_kwargs)
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−    
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−    self._script = safestring.mark_safe(self.ONCHANGE_JAVASCRIPT_FMT % {
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−        'arg_name': arg_name, 'page_path': page_path,})
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− 
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−    onchange_js_call = 'changeArg_%s(this)' % arg_name
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−    
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−    self.fields[field_name] = forms.ChoiceField(
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−        label='', choices=choices,
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−        widget=forms.widgets.Select(attrs={'onchange': onchange_js_call}))
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−      
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−  def as_table(self):
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−    """Returns form rendered as HTML <tr> rows -- with no <table></table>.
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−    
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−    Prepends <script> section with onchange function included.
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−    """
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−    return self._script + super(SelectQueryArgForm, self).as_table()
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−
+
−  def as_ul(self):
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−    """Returns form rendered as HTML <li> list items -- with no <ul></ul>.
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−    
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−    Prepends <script> section with onchange function included.
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−    """
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−    return self._script + super(SelectQueryArgForm, self).as_ul()
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−
+
−  def as_p(self):
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−    """Returns form rendered as HTML <p> paragraphs.
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−    
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−    Prepends <script> section with onchange function included.
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−    """
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−    return self._script + super(SelectQueryArgForm, self).as_p()
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−
+
−
+
−DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT = 'select_query_arg_%(arg_name)s'
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−
+
−def makeSelectQueryArgForm(
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−    request, arg_name, initial_value, choices,
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−    field_name_fmt=DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT):
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−  """Wrapper that creates a customized SelectQueryArgForm.
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−
+
−  Args:
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−    request: the standard Django HTTP request object
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−    arg_name: the URL query parameter that determines which choice is
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−      selected in the selection control
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−    initial_value: the initial value of the selection control
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−    choices: list (or tuple) of value/label string two-tuples, for example:
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−      (('10', '10 items per page'), ('25', '25 items per page'))
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−    field_name_fmt: optional form field name format string; default is
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−      DEF_SELECT_QUERY_ARG_FIELD_NAME_FMT; contains these named format
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−      specifiers:
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−        arg_name: replaced with the arg_name argument
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−
+
−  Returns:
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−    a Django form implementing a query argument selection control, for
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−    insertion into a template
+
−  """
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−  field_name = field_name_fmt % {'arg_name': arg_name}
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−  return SelectQueryArgForm(request.path, arg_name, choices, field_name,
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−                            initial={field_name: initial_value})