I am trying to raise ValidationError if a duplicate entry found in an inlineformset, just like in the docs: Custom formset validation I'm using a debugging tool and stepping through the code. It successfully reaches the line: raise ValidationError("Check Duplicate Entry"), and subsequently, in the view it takes the else statement instead proceeding with if formset.is_valid. I print(formset.non_form_errors) just as in the docs. However, the example in the docs returns a list at this stage with the error message inside it. In my case, I get <bound method BaseFormSet.non_form_errors of <django.forms.formsets.MyInlineFormSet object at 0x7fcc22e89610>> The template renders with the form data but the validation error does not appear to say what is wrong. I'm missing something for sure. Any help appreciated.
class MyInlineFormSet(BaseInlineFormSet):
def __init__(self, *args, **kwargs):
super(MyInlineFormSet, self).__init__(*args, **kwargs)
for form in self.forms:
form.empty_permitted = False
def clean(self):
if any(self.errors):
return
mylist = []
for form in self.forms:
myfield_data = form.cleaned_data.get("myfield")
if myfield_data in mylist:
raise ValidationError("Check Duplicate Entry")
mylist.append(myfield_data)
My tempate just has this:
{% block content %}
<section class="container-fluid">
{% crispy form %}
</section>
{% endblock content %}
Side Note: Any field validation errors against specific fields do show up. But there I am writing the errors like so: self._errors["fieldname"] = self.error_class(["Error in field, please double check"]) Not sure why raise ValidationError is not working for the formset
SOLVED! My formset is a crsipy form within a crispy form. The overall form is rendered in the template linked to the view. But I should have mentioned, I have a separate template containing the markup for the formset.
<div class="row justify-content-center">
<div class="col-7">
{{ formset.management_form | crispy }}
{% for form in formset.forms %}
<h3>Form {{forloop.counter}}</h3>
{% crispy form %}
{% endfor %}
</div>
<br>
</div>
So I just needed to add {{ formset.non_form_errors }} below formset.management_form.
Related
I have a SurveyForm where I create dynamically my fields. Here's the most basic code I could do and still have my problem:
class SurveyForm(forms.Form):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fields = []
self.fields_alone = []
new_field = forms.CharField(label=f'1 - 2: This is the question',
widget=widgets.Input(attrs={}))
self.fields.append(('id_1', new_field))
self.fields_alone.append(new_field)
self.fields = OrderedDict(self.fields)
In my template, when I do a "classical" loop I can display the fields and it works, but the second loop, which is supposed to access to the same fields, doesn't work:
<form action="" method="post">
{% for field in form %}
{{ field.label }} :{{ field }} <br>
{% endfor %}
{% for field in form.fields_alone %}
{{ field.label }} :{{ field }} <br>
{% endfor %}
</form>
The second loop display the field as a string like <django.forms.fields.CharField object at 0x0000012C00EF60D0>
What am I missing to display is like the "classical" loop?
I found the problem. It's in the source code of Django.
Django can only convert fields to HTML if they are BoundField. The problem is that you can access to the BoundField "version" of the fields of your form through iteration on the form itself.
In the django/forms/forms.py:
def __getitem__(self, name):
# blabla code
if name not in self._bound_fields_cache:
self._bound_fields_cache[name] = field.get_bound_field(self, name)
So you can get HTML code only through an iteration on the form or direct access to a field via form['myfield'].
So in my form I did:
class SurveyForm(forms.Form):
def field_by_id(self, field_id):
return self[field_id]
Then I've made a template tag in my application which is:
#register.filter(name='field_by_id')
def field_by_id(arg1, arg2):
"""
Returns the result of field_by_id() (= method has to exist in arg1!)
Usage: {{ form|field_by_id:XXX }} (XXX = field id string)
:param arg1: object of class Form
:param arg2: field id string
:returns corresponding field
"""
return arg1.field_by_id(arg2)
and then in my template, I use it like this:
{% for question_group, questions in form.question_groups.items %}
{% for question, answers in questions.items %}
{% for answer in answers %}
{% with form|field_by_id:answer as field %}
{{ field.label }} :{{ field }} <br>
{% endwith %}
{% endfor %}
{% endfor %}
{% endfor %}
And it works. Tricky solution, but I have many sub-groups (I could have used FormSet's for a single sub-group).
The fields list is meant to store the form fields. Whereas fields_alone isn't.
That is also the reason why you are able to loop over the form itself and not over form.fields.
Since I cant figure out why you need to have this other list I suggest that you add all the fields to the actual fields list.
Comment if there are any further questions to this problem
Here:
self.fields = []
You're overwriting the form's own fields ordereddict. You just want to add to it:
self.fields["whatevernameyouwant"] = new_field
(works on django 1.11, not tested on 2.x / 3.x)
EDIT:
the problem is when I try to use the fields through another property
You mean the form.fields_alone thing ? Well, you can always make it a property instead:
class YourForm(...):
def __init__(...)
# ....
self._fields_alone = []
self.fields["whatevernameyouwant"] = new_field
self.fields_alone.append("whatevernameyouwant")
#property
def fields_alone(self):
for name in self._fields_alone:
yield self[name]
But it won't remove this field from the "normal" form iterator (for field in form) so you'll have the field twice, so you'd also need to redefine __iter__ too:
def __iter__(self):
for name in self.fields:
if name not in self._fields_alone:
yield self[name]
How can I access if a field has)errors at the level of widget?
Using default I tried:
{% if widget.attributes.has_errors %} or {% if widget.has_errors %}
but are not working.
I use custom widget templates, I'm thinking to use a custom form Field and overwrite the default field.
I know clean method exist but I don't know how to push to the widget the dynamic(non default) data/attributes I want.
I tried:
class AWidget(forms.Widget):
def get_context(self, name, value, attrs):
context = super().get_context(name, value, attrs)
has_errors = context['widget']['attrs'].pop('has_errors', None)
context['widget']['has_errors'] = has_errors
It works for errors but I don't know if is the best option plus I want to pass other values/attributes from Form Field,and I think will be better to try to overwrite the Form Field but I don't know exactly how.
Also accessing individual attributes using:
{{ widget.attrs.maxlength }} or {{ widget.attrs.items.maxlength }}
even if accedes in a for loop works
I know I can add a parent div with a class of error:
<div class="{% if form.field.errors %}pass_error{% endif %}">
{{ form.field }}
</div>
but, that implies big changes at the css level.
I already overwrite all Django widgets with custom widgets, on error I don't need just to change a border color, but to show or not different elements of the widget template and the position of some of them change.
I already modify the based widget to add errors, but I'm looking to do it in a more elegant way at the field level by passing from the field to the widget, parameters depending on error type.
So my question is what I need to overwrite to pass from field to widget errors and other variables ?
Not sure whether this could help in your specific use case ... but just in case, please note that when you build your form in the view, you can add extra parameters as needed, then pass them down to your custom widget.
Working example:
file "forms.py"
from django import forms
def build_ingredient_form(unit):
"""
Ingredient form factory
Here we build the form class dynamically, in order to acces 'unit' via closure.
References:
http://stackoverflow.com/questions/622982/django-passing-custom-form-parameters-to-formset#623030
"""
class IngredientForm(forms.Form):
#quantity = forms.DecimalField(max_digits=10)
quantity = UnitField(unit, required=False)
...
return IngredientForm
file "fields.py"
from django import forms
from .fields import UnitField
class UnitField(forms.CharField):
"""
Custom field to support UnitWidget
References:
- http://tothinkornottothink.com/post/10815277049/django-forms-i-custom-fields-and-widgets-in
"""
def __init__(self, unit, *args, **kwargs):
self.unit = unit
super(UnitField, self).__init__(*args, **kwargs)
self.widget = UnitWidget(unit)
...
file "widgets.py"
from django import forms
from .models import Unit
class UnitWidget(forms.TextInput):
def __init__(self, unit, attrs=None):
if unit is None:
self.unit = Unit()
else:
self.unit = unit
...
Well a widget is how you will render the field's data/value into the HTML rendered template, that's the only function of widgets, look the following example taken from the docs:
>>> name = forms.TextInput(attrs={'required': True})
>>> name.render('name', 'A name')
'<input name="name" type="text" value="A name" required>'
>>>
>>> name = forms.TextInput(attrs={'required': False})
>>> name.render('name', 'A name')
'<input name="name" type="text" value="A name">'
So, widgets are not aware of the data is valid(has errors) or not and should remain that way.
Is not a good idea to handle any data error/validation at the widget level, you want, I can ensure that, that if you change how your field looks like (the widget), your validations keeps working.
Said that ...
How can I access field errors?
When you are rendering a form you can do it field by field lets take this form by example:
class LoginForm(forms.Form):
username = forms.CharField(max_length=255)
password = forms.CharField(widget=forms.PasswordInput)
you can write to temlate:
<form action="." method="get">
<p>{{ loginform.username.label }}: {{ loginform.username }}</p>
<p>{{ loginform.password.label }}: {{ loginform.password}}</p>
<button type="submit">submit</button>
</form>
And this will render something like the following:
Now, suppose your form won't admit passwords with less than 8 characters:
class LoginForm(forms.Form):
username = forms.CharField(max_length=255)
password = forms.CharField(widget=forms.PasswordInput)
def clean_password(self):
password = self.cleaned_data['password']
if len(password) < 8:
raise forms.ValidationError(
"Password must have at least 8 characters, it has only %(password_length)s",
code='invalid password',
params={'password_length': len(password)}
)
return password
You can access the password errors like this:
<form action="." method="get">
{% csrf_token %}
<p>{{ form.username.label }}: {{ form.username }}</p>
<p>{{ form.password.label }}: {{ form.password}}</p>
<ul>
{% for error in form.password.errors %}
<li>{{ error }}</li>
{% endfor %}
</ul>
<button type="submit">submit</button>
</form>
And now if you type a short password ...
I want the control to look different if there are errors.
You can add some style if there are errors just use {% if ... %} in your template code:
<p>
{{ form.password.label }}:
<span class="{% if form.password.errors %}pass_error{% endif %}">
{{ form.password }}
</span>
</p>
With CSS:
<style>
.pass_error input {
border-color: red;
}
</style>
And this is the result:
Conlusion.
Validate and handle data errors in the form or using validators, use widgets for display the data, of course, you can customize how the data is presented since you can specify a custom template for your widget.
I also recommend django-widget-twaeks if you want to add attributes to your widget in template code. This apps allows you to write code like (example from the app docs):
{% load widget_tweaks %}
<!-- change input type (e.g. to HTML5) -->
{% render_field form.search_query type="search" %}
<!-- add/change several attributes -->
{% render_field form.text rows="20" cols="20" title="Hello, world!" %}
<!-- append to an attribute -->
{% render_field form.title class+="css_class_1 css_class_2" %}
<!-- template variables can be used as attribute values -->
{% render_field form.text placeholder=form.text.label %}
My model formset without even defining "extra" parameters in modelformset_factory is rendering one extra field in the template. I have tried many variations but it didn't work. If I print the form (the model form) on the command line it just prints a single form field as required but on model formset it prints 2 by default.
Here is my code.
models.py
class Direction(models.Model):
text = models.TextField(blank=True, verbose_name='Direction|text')
forms.py
class DirectionForm(forms.ModelForm):
class Meta:
model = Direction
fields = ['text',]
views.py
def myview(request):
Dirset = modelformset_factory(Direction, form=DirectionForm)
if request.method == "POST":
dir_formset = Dirset(request.POST or None)
if dir_formset.is_valid():
for direction in dir_formset:
text = direction.cleaned_data.get('text')
Direction.objects.create(text=text)
return render(request, "test/test.html", {'DirFormSet':Dirset})
template
{% block content %}
<form method="POST">{% csrf_token %}
<div id="forms">
{{DirFormSet.management_form}}
{% for form in DirFormSet %}
{{form.text}}
{% if error in form.text.errors %}
{{error|escape}
{% endif %}
{% endfor %}
</div>
<button id="add-another">add another</button>
<input type="submit" />
</form>
{% endblock %}
As a side note, if I submit data on this form it gives the following error.
Error
Exception Type: MultiValueDictKeyError
Exception Value:"u'form-0-id'"
By default, modelformset_factory creates one extra form. If you don't want any extra forms, set extra=0.
Dirset = modelformset_factory(Direction, form=DirectionForm, extra=0)
The KeyError is because you have not included the form's id field in your template. You should have something like:
{% for form in dir_formset %}
{{ form.id }}
{{ form.text }}
...
{% endfor %}
Note that you should be passing the formset instance dir_formset when rendering the template, not the class DirFormSet. Your view should be something like
return render(request, "test/test.html", {'dir_formset': dir_formset})
then the template should be updated to use dir_formset instead of DirFormSet.
Problem description (Django 1.7):-
Simple form is rendered containing input fields and some template variables. The template variables are set in the supporting view and show some boilerplate legal text.
I have a custom "clean" method that checks the input field values and sets validation errors as needed.
If errors have occurred, the form is re-displayed with the correct error messages by the fields that are in error.
However, the template variables are lost, i.e.
{{ my-template-variable }} that when the form is initially rendered is OK is then not set when the form is re-rendered to show the errors.
I understand why this is happening, but can anyone advise how I can reset the template variable in the clean method so this works as expected?
Here's the code:-
views.py
def form1(request):
legal_text = "Some long legal paragraph ...."
if request.method == 'POST':
form = form1(request.POST)
# do stuff with the posted values ...
else:
form = form1()
return render(request,'form11.html', {'form': form, 'legal_text': legal_text})
forms.py
class form1(forms.Form):
# form contains lots of input questions 'q1', 'q2' etc that are cross-validated
def clean(self):
cleaned_data = super(form1,self).clean()
if not cleaned_data.get('q1'):
self._errors['q1'] = 'Please provide a selection'
if not cleaned_data.get('q2'):
self._errors['q2'] = 'Please provide a selection'
Q1_CHOICES = (('10', 'Yes',), ('01', 'No',),)
q1 = forms.ChoiceField(required=False,label="This is question 1",help_text="Some arbitrary help text",widget=forms.RadioSelect,choices=Q1_CHOICES)
Q2_CHOICES = (('10', 'Yes',), ('01', 'No',),)
q2 = forms.ChoiceField(required=False,label="This is question 1",help_text="Some arbitrary help text",widget=forms.RadioSelect,choices=Q2_CHOICES)
# more questions omitted ...
form1.html (snippet)
<html>
<body>
{{ legal_text }} <!-- this is NOT displayed properly when errors occur -->
<h4><strong>{{ form.q1.label }}</strong></h4>
{% if form.q1.errors %}
<div class="alert alert-danger" role="alert">{{form.q1.errors }}</div>
{% endif %}
<br/>
{{ form.q1.help_text }}
<br/><br/>
{{ form.q1 }}
<br/>
<h4><strong>{{ form.q2.label }}</strong></h4>
{% if form.q2.errors %}
<div class="alert alert-danger" role="alert">{{form.q2.errors }}</div>
{% endif %}
<br/>
{{ form.q2.help_text }}
<br/><br/>
{{ form.q2 }}
</body>
</html>
Here you are overriding the form clean method and not returning clean_data. Replace your code like
def clean(self):
cleaned_data = super(form1,self).clean()
if not cleaned_data.get('q1'):
self._errors['q1'] = 'Please provide a selection'
if not cleaned_data.get('q2'):
self._errors['q2'] = 'Please provide a selection'
return self.cleaned_data
I want to display my non_field_erors in my template. So far, I can display all kind of errors of my forms with:
-> base.html
{% if form.errors %}
{% for field in form %}
{% if field.errors %}
<div class="ui-state-error ui-corner-all notification" >
<p>
<span class="ui-icon ui-icon-alert"></span>
{{ field.label_tag }}:{{ field.errors|striptags }}
<a class="hide" onClick="hideBar(this)">hide</a>
</p>
</div>
{% endif %}
{% endfor%}
{% endif %}
AND
{{ form.non_field_errors }}
I've added a new form which has only an IntegerField:
class MerchantForm(forms.ModelForm):
price = forms.IntegerField(widget=forms.TextInput(attrs={'class':'small'}))
def clean_price(self):
price = self.cleaned_data.get('price')
if price == 120:
raise forms.ValidationError('error blah.')
return price
When I post price as 120, I don't get any validation errors in my page.
And my view is:
def bid(request,product_slug):
.
.
form = MerchantForm()
context = RequestContext(request,{
'form':form,
....
})
if request.method == 'POST':
form = MerchantForm(request.POST)
if form.is_valid():
return HttpResponse('ok')
# else:
# return HttpResponse(form.errors.get('__all__'))
return render_to_response('bid.html',context_instance=context)
I can retrieve the error with commented lines but I don't want to do that in views.py. Any ideas ?
Oh dear.
First of all, why are you asking about non_field_errors when the code snippet you post clearly has the error as being raised in clean_price, and therefore is associated with ths price field?
Secondly, your view code is upside down. You create an empty form instance, and add it to the context. Then you create another form instance, bound to the POST data, but don't put it into the context. So the template never sees the bound form, so naturally you never see any validation errors in the template.