How do I generate dynamic fields in WTForms - python

I am trying to generate a form in WTForms that has dynamic fields according to this documentation http://wtforms.simplecodes.com/docs/1.0.2/specific_problems.html#dynamic-form-composition
I have this subform class which allows users to pick items to purchase from a list:
class Item(Form):
itmid = SelectField('Item ID')
qty = IntegerField('Quantity')
class F(Form):
pass
There will be more than one category of shopping items, so I would like to generate a dynamic select field based on what categories the user will choose:
fld = FieldList(FormField(Item))
fld.append_entry()
but I get the following error:
AttributeError: 'UnboundField' object has no attribute 'append_entry'
Am I doing something wrong, or is there no way to accomplish this in WTForms?

I ran into this issue tonight and ended up with this. I hope this helps future people.
RecipeForm.py
class RecipeForm(Form):
category = SelectField('Category', choices=[], coerce=int)
...
views.py
#mod.route('/recipes/create', methods=['POST'])
def validateRecipe():
categories = [(c.id, c.name) for c in g.user.categories.order_by(Category.name).all()]
form = RecipeForm(request.form)
form.category.choices = categories
...
#mod.route('/recipes/create', methods=['GET'])
def createRecipe():
categories = [(c.id, c.name) for c in g.user.categories.order_by(Category.name).all()]
form = RecipeForm(request.form)
form.category.choices = categories
return render_template('recipes/createRecipe.html', form=form)
I found this post helpful as well

class BaseForm(Form):
#classmethod
def append_field(cls, name, field):
setattr(cls, name, field)
return cls
from forms import TestForm
form = TestForm.append_field("do_you_want_fries_with_that",BooleanField('fries'))(obj=db_populate_object)
I use the extended class BaseForm for all my forms and have a convenient append_field function on class.
Returns the class with the field appended, since instances (of Form fields) can't append fields.

Posting without writing full code or testing the code, but maybe it will give you some ideas. Also this could maybe only help with the filling the needed data.
You need to fill choices for SelectField to be able to see the data and be able to select it. Where you fill that? Initial fill should be in the form definition, but if you like dynamic one, I would suggest to modify it in the place where you creating this form for showing to the user. Like the view where you do some form = YourForm() and then passing it to the template.
How to fill form's select field with choices? You must have list of tuples and then something like this:
form.category_select.choices = [(key, categories[key]) for key in categories]
form.category_select.choices.insert(0, ("", "Some default value..."))
categories here must be dictionary containing your categories in format like {1:'One', 2:'Two',...}
So if you will assign something to choices when defining the form it will have that data from the beginning, and where you need to have user's categories, just overwrite it in the view.
Hope that will give you some ideas and you can move forward :)

have you tried calling append_entry() on the form instance instead of the FieldList definition?
class F(Form)
fld = FieldList(SelectField(Item))
form = F()
form.fld.append_entry()

This is how i got it to work.
class MyForm(FlaskForm):
mylist = SelectField('Select Field', choices=[])
#app.route("/test", methods=['GET', 'POST']
def testview():
form = MyForm()
form.mylist.choices = [(str(i), i) for i in range(9)]
Strangely this whole thing stops working for me if i use coerce=int. I am myself a flask beginner, so i am not really sure why coerce=int causes issue.

WTForms Documentation : class wtforms.fields.SelectField
Select fields with dynamic choice values:
class UserDetails(Form):
group_id = SelectField(u'Group', coerce=int)
def edit_user(request, id):
user = User.query.get(id)
form = UserDetails(request.POST, obj=user)
form.group_id.choices = [(g.id, g.name) for g in Group.query.order_by('name')]

Related

Django forms initial value user_full_name

Is the any solution to get django's user_full_name as a initial value for form? My idea was to display a django's form on the end of shopping to finish a order. I want also do put into a form total value, but this is for later.
I did something like this:
user_dane = request.user.get_full_name
koszyk = request.session.get('koszyk', [])
produkty = list(Produkt.objects.filter(pk__in=koszyk))
suma_cen = Produkt.objects.filter(pk__in=koszyk).aggregate(suma=Sum('cena'))
suma_wszystkich_cen = suma_cen['suma']
form=ZamowienieForm(initial={'imie_nazwisko':user_dane, 'kwota_do_zaplaty':suma_wszystkich_cen})
but this is working only when request.method is POST.
if request.method =='POST':
form = ZamowienieForm()
According to documentation I shouldn't initial a empty form with POST... Is there any chance to have a user full name into a form?
Here is the form class:
class ZamowienieForm(forms.ModelForm):
class Meta:
model = Zamowienie
fields = ('imie_nazwisko', 'kwota_do_zaplaty', 'miejscowosc',
'ulica','numer_domu', 'numer_mi‌​eszkania', 'kod_pocztowy',)
class NewMeta:
readonly = ('imie_nazwisko','kwota_do_zaplaty',)
Maybe try something like this inside ZamowienieForm class
def __init__(self, *args, **kwargs):
super(ZamowienieForm, self).__init__(*args, **kwargs)
self.fields['imie_nazwisko'] = self.initial.get('imie_nazwisko')
self.fields['kwota_do_zaplaty'] = self.initial.get('kwota_do_zaplaty')
Although I don't understand why "initial" is not working out of the box
In this case, you only need to initialize your form once, and not inside a conditional check if the request is a GET or POST:
def your_view(request):
form = ZamowienieForm(
request.POST or None,
initial={'imie_nazwisko': request.user.get_full_name(),
'kwota_do_zaplaty': suma_wszystkich_cen}
)
if request.method == 'POST' and form.is_valid():
# do whatever
This way you are always passing in the initial value, and if request.method == 'GET', then None is passed as the first positional argument to the form.
Also, user.get_full_name is an instance method, not a property, so using request.user.get_full_name only returns the bound method, not the actual value. You have have to call the function using ()
Finally, this will only work for users that are authenticated. The anonymous user object in Django won't return any user-specific information.

iterate over django form results (not in a template)

I am trying to iterate over form results and I can't help but think that I am re-inventing the wheel here.
filterlist = []
if request.POST:
form = FilterForm(request.POST)
if form.is_valid():
for key, value in form.cleaned_data.iteritems():
filterlist.append(key)
filterlist.append(value)
This works, but seems very awkward and creates lots of other problems. For example the values come back with u' so I have to use value.encode("utf8") but then if a value is None it throws in error. So now I have to check if it is None, if not then encode. There has to be a better way.
EDIT: What I am trying to do.
I am trying to filter what is shown on a page. The problem I am running into is that if a value is empty (the user don't fill the box because they only want to filter against one object) then I get no results. For example a user wants to search for all books by the author name "Smith" but doesn't want to search against a genre.
results = Books.objects.filter(author=author, genre=genre)
The user would get no results because this is an AND search. But, if a user put in "Smith" for the author and "mystery" for the genre then it works exactly like I want it to, only giving results where both are true.
So, I am trying to eliminate the empty stuff by iterating over the form results. Like I said I am probably re-inventing the wheel here.
In Python 3 use:
for key, value in form.cleaned_data.items():
If the field names are the same in the model and the form, try this:
filter = {}
if request.method == 'POST':
form = FilterForm(request.POST)
if form.is_valid():
for key, value in form.cleaned_data.iteritems():
if value:
filter[key] = value
results = Books.objects.filter(**filter)
Python is one of the few languages having named parameters. You can assemble a dict with the non-empty form fields and pass it to the filter method using the kwargs unpacking operator **.
For example:
kwargs = {"author": "Freud"}
results = Books.objects.filter(**kwargs)
Is the same as:
results = Books.objects.filter(author="Freud")
I think the problem is that by default the Model form is not valid if a form field does not have a value entered by the user, if you don`t require the field every time from the user you need to set the required field to false in the ModelForm class in forms.py as shown in the code below. Remember that the field is set false only in the model form not in the model itself
class myForm(forms.ModelForm):
myfield_id = forms.CharField(required=False)
myfield_foo = forms.CharField(required=False)
myfield_bar = forms.CharField(required=False)
myfield_name = forms.CharField(required=False)
class Meta:
model = myModel
exclude = ('myfield_ex','myfield_file')
fields = ['myfield_id','myfield_foo','myfield_bar','myfield_name',]
After you have the form entered by the user what you need is use the Q object which can be used to create complex queries as described in the manula page here
https://docs.djangoproject.com/en/1.7/topics/db/queries/#complex-lookups-with-q
A simple example code would look like
if form.is_valid():
qgroup = []
for key,value in form.cleaned_data.iteritems():
if value:
q_name = Q(**{"%s"%format(filterKey[key]) : value})
qgroup.append(q_name)
q = None
# can use the reduce as shown here qgroup = reduce(operator.or_, (Q(**{"{0}".format(filterKey[key]): value}) for (key,value) in form.cleaned_data.iteritems()))
for key,value in form.cleaned_data.iteritems():
if value:
q_name = Q(**{"%s"%format(filterKey[key]) : value})
qgroup.append(q_name)
for x in qgroup:
q &= x ### Or use the OR operator or
if q:
resultL = myModel.objects.filter(q).select_related()
The filterKey can look something on the lines of
filterKey = {'myfield_id' : "myfield_id",
'myfield_foo' : "myfield_foo__icontains",
'myfield_bar' : "myfield_bar__relative_field__icontains",
}

How to override createView to save multiple data entry

using CreateView class, I want to save multiple data entries.
example inputs:
item is "apple,banana,carrots"
location is "location 1"
I want to save them to database like this:
[apple, location 1]
[banana, location 1]
[carrots, location 1]
#model.py
class Inventory(models.Model):
item = models.CharField(max_length=14)
location = models.CharField(max_length=10)
#forms.py
class InventoryCreateForm(forms.ModelForm):
item = forms.CharField(widget=forms.Textarea(attrs={'rows': 8,
'cols': 14}))
class Meta:
model = Inventory
#views.py
class InventoryCreateView(CreateView):
model = Inventory
form_class = InventoryCreateForm
Thank you
You need to override the "form_valid()" method used by the createview.
You then need to read in the form data
def form_valid(self,form):
self.object = form.save(commit=False)
foo = self.object.bar #your data is in the object
Then because you are using a textfield you need to somehow split the data passed into the form and loop over those values. Ideally you will want a list of items ['apple', 'banana', 'pear']
then take the location out of the list and store that into a variable that can be used later on location_variable.
Once you have the data in the form you want you then need to instantiate the Inventory model
from foo.models import Inventory #import at the top of your file
for item is list:
inventory = Inventory()
inventory.item = item
inventory.location = location_variable
inventory.save()
I hope this answer can help you in some way, if you would like further details on Class based view, visit ccbv where all of the information for each view is listed.
Otherwise you can look in the django Form docs for a more suitable form to use.
hopefully this helps anyone else who comes to this page.
Here is what I did:
class TrainingBulkCreateForm(ModelForm):
# todo: could we make the original user object a multiple choice field instead?
extra_user = forms.ModelMultipleChoiceField(queryset=User.objects.filter(is_active=True), required=True)
class Meta(object):
model = Training
fields = '__all__'
def post(self, request, *args, **kwargs):
result = super().post(request, *args, **kwargs)
users = request.POST.getlist('extra_user')
if users:
# modify request.POST data then re-save the additional users
for user in users:
# Need to copy the data because the initial QueryDict is immutable data
postdata_copy = request.POST.copy()
postdata_copy['user'] = user
form2 = TrainingBulkCreateForm(postdata_copy)
form2.save()
return result
I have my item field (mine is user) split into two form fields - the original item which is 1 object like apple.
Then I also have extra_user as a second form field. This takes multiple objects like [banana, carrots]
In the view I invoke the super().post(...) to save the initial apple object.
Then I check for the extra_user field to see if there are multiple foods. If there are extras, I copy the immutable QueryDict object request.POST as postdata_copy.
Then I modify postdata_copy so instead of having apple we replace with banana. (This basically just duplicates the apple form into a new copy with banana and re-saves the form). Then we loop again and replace apple with carrots.
Note that my Form object uses ModelMultipleChoiceField for extra_user object. This has better data integrity than typing in raw text.

How to initialize django-form data type field from a given choices?

First of all: I am not able to find out the proper Title of this question.
Anyhow the question is:
I have to fill a form at template and the fields of this form are user dependent. For example you passes integer (integer is not a datatype) as a parameter to the method and it should returns like this:
fileds = forms.IntegerField()
If you pass bool then it should like this:
fields = forms.BooleanField()
So that i can use them to create my form. I tried with this code but it returns into the form of string.
Some.py file:
choices = (('bool','BooleanField()'),
('integer','IntegerField()'))
def choose_field():
option = 'bool' # Here it is hardcoded but in my app it comes from database.
for x in choices:
if x[0]==option:
type = x[1]
a = 'forms'
field = [a,type]
field = ".".join(field)
return field
When i print the field it prints 'forms.BooleanField()'. I also use this return value but it didn't work. Amy solution to this problem?
The simpliest way is to create your form class and include fields for all possible choices to it. Then write a constructor in this class and hide the fields you don't want to appear. The constructor must take a parameter indicating which fields do we need. It can be useful to store this parameter in the form and use it in clean method to correct collected data accordingly to this parameter.
class Your_form(forms.ModelForm):
field_integer = forms.IntegerField()
field_boolean = forms.BooleanField()
def __init__(self, *args, **kwargs):
option = kwargs["option"]
if option == "integer":
field_boolean.widget = field_boolean.hidden_widget()
else:
field_integer.widget = field_integer.hidden_widget()
super(Your_form, self).__init__(*args, **kwargs)
In your controller:
option = 'bool'
form = Your_form(option=option)

How to get the label of a choice in a Django forms ChoiceField?

I have a ChoiceField, now how do I get the label when I need it?
class ContactForm(forms.Form):
reason = forms.ChoiceField(choices=[("feature", "A feature"),
("order", "An order")],
widget=forms.RadioSelect)
form.cleaned_data["reason"] only gives me the feature or order values or so.
See the docs on Model.get_FOO_display(). So, should be something like :
ContactForm.get_reason_display()
In a template, use like this:
{{ OBJNAME.get_FIELDNAME_display }}
This may help:
reason = form.cleaned_data['reason']
reason = dict(form.fields['reason'].choices)[reason]
This the easiest way to do this: Model instance reference: Model.get_FOO_display()
You can use this function which will return the display name: ObjectName.get_FieldName_display()
Replace ObjectName with your class name and FieldName with the field of which you need to fetch the display name of.
If the form instance is bound, you can use
chosen_label = form.instance.get_FOO_display()
Here is a way I came up with. There may be an easier way. I tested it using python manage.py shell:
>>> cf = ContactForm({'reason': 'feature'})
>>> cf.is_valid()
True
>>> cf.fields['reason'].choices
[('feature', 'A feature')]
>>> for val in cf.fields['reason'].choices:
... if val[0] == cf.cleaned_data['reason']:
... print val[1]
... break
...
A feature
Note: This probably isn't very Pythonic, but it demonstrates where the data you need can be found.
You can have your form like this:
#forms.py
CHOICES = [('feature', "A feature"), ("order", "An order")]
class ContactForm(forms.Form):
reason = forms.ChoiceField(choices=CHOICES,
widget=forms.RadioSelect)
Then this would give you what you want:
reason = dict(CHOICES)[form.cleaned_data["reason"]]
OK. I know this is very old post, but reading it helped me a lot. And I think I have something to add.
The crux of the matter here is that the the model method.
ObjectName.get_FieldName_display()
does not work for forms.
If you have a form, that is not based on a model and that form has a choice field, how do you get the display value of a given choice.
Here is some code that might help you.
You can use this code to get the display value of a choice field from a posted form.
display_of_choice = dict(dateform.fields['fieldnane'].choices)[int(request.POST.get('fieldname'))]
the 'int' is there on the basis the choice selection was a integer. If the choice index was a string then you just remove the int(...)
Im using #Andrés Torres Marroquín way, and I want share my implementation.
GOOD_CATEGORY_CHOICES = (
('paper', 'this is paper'),
('glass', 'this is glass'),
...
)
class Good(models.Model):
...
good_category = models.CharField(max_length=255, null=True, blank=False)
....
class GoodForm(ModelForm):
class Meta:
model = Good
...
good_category = forms.ChoiceField(required=True, choices=GOOD_CATEGORY_CHOICES)
...
def clean_good_category(self):
value = self.cleaned_data.get('good_category')
return dict(self.fields['good_category'].choices)[value]
And the result is this is paper instead of paper.
Hope this help
I think maybe #webjunkie is right.
If you're reading from the form from a POST then you would do
def contact_view(request):
if request.method == 'POST':
form = ContactForm(request.POST)
if form.is_valid():
contact = form.save()
contact.reason = form.cleaned_data['reason']
contact.save()
confirm that Ardi's and Paul's response are best for forms and not models. Generalizing Ardi's to any parameter:
class AnyForm(forms.Form):
def get_field_name_display(self, field_name):
return dict(self.fields[field_name].choices[self.cleaned_data[field_name]]
Or put this method in a separate class, and sub-class it in your form
class ChoiceFieldDisplayMixin:
def get_field_name_display(self, field_name):
return dict(self.fields[field_name].choices[self.cleaned_data[field_name]]
class AnyCustomForm(forms.Form, ChoiceFieldDisplayMixin):
choice_field_form = forms.ChoiceField(choices=[...])
Now call the same method for any Choice Field:
form_instance = AnyCustomForm()
form_instance.is_valid()
form_instance.get_field_name_display('choice_field_form')

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