I have the following form:
When one of the tickets is empty, my form sends me an error with that every field is required, now I am trying to check if the form value is empty, if it's empty I want to change it to 0, so form.is_valid() can be true.
The attached code doesn't work. It says string index out of range.
def reserve_ticket(request):
if request.method == 'POST':
quantities = request.POST.getlist('quantity')
for i in range(len(quantities)):
if not request.POST['quantity'][i]:
request.POST['quantity'][i] = 0
form = ReserveForm(request.POST)
if form.is_valid():
print("Hello world")
return HttpResponse("Hello world")
else:
return HttpResponse("Back to homepage")
It's not very clean to try to alter the post data. Instead, make the field optional in your form with required=False (or blank=True in the model field) so that there aren't form errors when the field is missing.
If it's a model form, you could set a default value on the field. Or, for a regular form you could override clean_<fieldname> and return 0 when the value isn't specified.
Related
I have a Model as follows:
class TankJournal(models.Model):
user = models.ForeignKey(User)
tank = models.ForeignKey(TankProfile)
ts = models.IntegerField(max_length=15)
title = models.CharField(max_length=50)
body = models.TextField()
I also have a model form for the above model as follows:
class JournalForm(ModelForm):
tank = forms.IntegerField(widget=forms.HiddenInput())
class Meta:
model = TankJournal
exclude = ('user','ts')
I want to know how to set the default value for that tank hidden field. Here is my function to show/save the form so far:
def addJournal(request, id=0):
if not request.user.is_authenticated():
return HttpResponseRedirect('/')
# checking if they own the tank
from django.contrib.auth.models import User
user = User.objects.get(pk=request.session['id'])
if request.method == 'POST':
form = JournalForm(request.POST)
if form.is_valid():
obj = form.save(commit=False)
# setting the user and ts
from time import time
obj.ts = int(time())
obj.user = user
obj.tank = TankProfile.objects.get(pk=form.cleaned_data['tank_id'])
# saving the test
obj.save()
else:
form = JournalForm()
try:
tank = TankProfile.objects.get(user=user, id=id)
except TankProfile.DoesNotExist:
return HttpResponseRedirect('/error/')
You can use Form.initial, which is explained here.
You have two options either populate the value when calling form constructor:
form = JournalForm(initial={'tank': 123})
or set the value in the form definition:
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
Other solution: Set initial after creating the form:
form.fields['tank'].initial = 123
If you are creating modelform from POST values initial can be assigned this way:
form = SomeModelForm(request.POST, initial={"option": "10"})
https://docs.djangoproject.com/en/1.10/topics/forms/modelforms/#providing-initial-values
I had this other solution (I'm posting it in case someone else as me is using the following method from the model):
class onlyUserIsActiveField(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(onlyUserIsActiveField, self).__init__(*args, **kwargs)
self.fields['is_active'].initial = False
class Meta:
model = User
fields = ['is_active']
labels = {'is_active': 'Is Active'}
widgets = {
'is_active': forms.CheckboxInput( attrs={
'class': 'form-control bootstrap-switch',
'data-size': 'mini',
'data-on-color': 'success',
'data-on-text': 'Active',
'data-off-color': 'danger',
'data-off-text': 'Inactive',
'name': 'is_active',
})
}
The initial is definded on the __init__ function as self.fields['is_active'].initial = False
As explained in Django docs, initial is not default.
The initial value of a field is intended to be displayed in an HTML . But if the user delete this value, and finally send back a blank value for this field, the initial value is lost. So you do not obtain what is expected by a default behaviour.
The default behaviour is : the value that validation process will take if data argument do not contain any value for the field.
To implement that, a straightforward way is to combine initial and clean_<field>():
class JournalForm(ModelForm):
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
(...)
def clean_tank(self):
if not self['tank'].html_name in self.data:
return self.fields['tank'].initial
return self.cleaned_data['tank']
If you want to add initial value and post other value you have to add the following :
or None after request.POST
form = JournalForm(request.POST or None,initial={'tank': 123})
If you want to add files or images also
form = JournalForm(request.POST or None,request.FILES or None,initial={'tank': 123})
I hope this can help you:
form.instance.updatedby = form.cleaned_data['updatedby'] = request.user.id
I also encountered the need to set default values in the form during development. My solution is
initial={"":""}
form=ArticleModel(request.POST)
if form.has_changed():
data = {i: form.cleaned_data[i] for i in form.changed_data}
data.update({key: val for key, val in init_praram.items() if key not in form.changed_data})
use form.has_changed ,if form.fields is required you can use this method
How I added the initial to the form:
I read #Sergey Golovchenko answer.
So I just added it to the form in if request.method == 'POST':.
But that's not where you place it, if you want to see what value it got before posting the form.
You need to put it in the form where the else is.
Example here from views.py
def myForm(request):
kontext = {}
if request.method == 'POST':
# You might want to use clean_data instead of initial here. I found something on a stack overflow question, and you add clean data to the Forms.py, if you want to change the post data. https://stackoverflow.com/questions/36711229/django-forms-clean-data
form = myModelForm(request.POST, initial={'user': request.user})
if form.is_valid():
form.save()
return redirect('/')
else:
# you need to put initial here, if you want to see the value before you post it
form = myModelForm(initial={'user': request.user})
kontext['form'] = form
return render(request, 'app1/my_form.html', kontext)
I have a project, where people will be able to create variables for a form, and then other users will fill that form. When they create the said form, they can chose the answer to be of 3 different types : From a list of value, an integer, or a string. Basically, I create a formset of all the variables the user created for this form, but if it is a list, I want to change the type of the input from a CharField to a ChoiceField.
So this is my view :
def insererDonnee(request, modele, contexte=-1):
variables = Variable.objects.filter(modele=modele)
varIter = variables.iterator()
DonneeFormSet = formset_factory(InsertDonneeForm, extra=variables.count())
submitAdress = "insererDonnee"
if request.POST:
formset = DonneeFormSet(request.POST)
else:
formset = DonneeFormSet()
for formx in formset:
formx.variable = varIter.next()
formx.nomVar = formx.variable.nom
formx.fields['valeur'].label = formx.nomVar
# Here I call setList to change the type
if formx.variable.type_variable in ["SOLIST", "LIST"]:
formx.setList(formx.variable)
And my form:
class InsertDonneeForm(forms.Form):
variable = Variable()
nomVar = 'Variable'
valeur = forms.CharField(label=nomVar, max_length=100)
def setList(self, variable):
choices = ListItem.objects.filter(variable=variable, modele=variable.modele)
valeur = forms.ModelChoiceField(queryset=choices)# or None)
print valeur
The last print was just to see if the field was indeed changed, which it is, but if I do the same print in my view after calling setList, my field are still
Is there anyways I could choose the appropriate type after creating the form?
Found the solution. The method setList, instead of changing the field directly in the form, now returns the new Choice field :
def setList(self, variable):
choices = ListItem.objects.filter(variable=variable, modele=variable.modele)
valeur = forms.ModelChoiceField(queryset=choices)
return valeur
And then in the view, I just have to assign the newly created field to the old field I want to change:
if formx.variable.type_variable in ["SOLIST", "LIST"]:
formx.fields['valeur']= formx.setList(formx.variable)
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_mieszkania', '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.
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",
}
I tried this, but there is no update done in django.
def update_product(request):
a= ProductForm(instance=Product.objects.get(product_id =2))#static id
render_to_response('profiles/updateproduct.html',{'form': a},RequestContext(request))
if request.method == "POST":
form = ProductForm(request.POST, instance=a)
if form.is_valid():
j=form.save(commit=False)
j.save
confirmation_message = "product information updated successfully!"
return HttpResponse("hhhh")
else:
form = ProductForm( instance = a )
You never actually call the model's save method since you are missing (). you must supply these in order to call the method.
j = form.save(commit=False)
j.save()
As a side note, since you are not doing anything to the model before saving it, you can simply replace these two lines with
j = form.save()
no real need here for the commit=False part.