When I load my view at : localhost:8000/Scan, it throws an issue of:
TypeError on views.py in Scan, line 27:
form = Scan() # Otherwise, set the form to unbound
Any idea what I'm doing wrong here? I tried researching, but couldn't find the answer. (Django newbie here) . Thank you all!
Views.py
from django.http import HttpResponse
from Scanner.forms import SubmitDomain
def Scan(request):
if request.method == 'POST': # If the form has been submitted...
form = SubmitDomain(request.POST) # A form bound to the POST data
if form.is_valid(): # If form input passes initial validation...
form.cleaned_data['domainNm'] ## clean data in dictionary
try:
## check if Tld Table has submitted domain already
from Scanner.models import Tld
Tld.objects.get(domainNm=form.cleaned_data['domainNm'])
except Tld.DoesNotExist:
print "Would you like to create an account?"
## redirect to account creation
else:
print "Do you have an account? Please login."
## redirect to account login
else:
form = Scan() # Otherwise, set the form to unbound
Forms.py
from django.forms import ModelForm
from Scanner.models import Tld
class SubmitDomain(ModelForm):
class Meta:
model = Tld #Create form based off Model for Tld
fields = ['domainNm',]
def clean_domainName(self):
val = self.clean_domainName('domainNm')
return val
## This creates the form.
form = SubmitDomain()
In your model form:
from django.forms import ModelForm
from Scanner.models import Tld
class SubmitDomainForm(ModelForm):
class Meta:
model = Tld
fields = ['domainNm']
def clean_domainName(self):
val = self.cleaned_data.get('domainNm')
if Tld.objects.filter(domainNm=val).count() > 0:
raise forms.ValidationError(u'Sorry that domain already
exists, etc, etc')
return val
In your view, do:
from django.shortcuts import render
from Scanner.forms import SubmitDomainForm
def scan(request): # functions should start with a lowercase letter
# Bind the post data to the form, if it exists.
# No need for a separate if statement here
form = SubmitDomainForm(request.POST or None)
if request.method == 'POST':
if form.is_valid():
# save your model form, or do something else
return render(request, 'your-template.html', {'form': form})
Hope that helps you out. Your view is currently instantiating the wrong type of object for the form, hence the TypeError. Your current clean method on your model form will never validate anything. It just sets the value equal to the clean function. Instead of cluttering your view with form validation logic, put that into the clean method of the form for that field and you can raise exceptions for different conditions.
it fails when reuqest.method != "POST", in which case form is not defined
The problem is not specific to django, it's basic python. Your indentation is wrong. The code should probably look like this:
if request.method == 'POST':
form = SubmitDomain(request.POST)
if form.is_valid(): # indent fixed here
form.cleaned_data['domainNm']
Related
This is my views function,
def studentcreate(request):
reg = StudentForm()
string = "Give Information"
if request.method == "POST":
reg = StudentForm(request.POST)
string = "Not Currect Information"
if reg.is_valid():
reg.save()
return render('http://localhost:8000/accounts/login/')
context = {
'form':reg,
'string': string,
}
return render(request, 'student.html', context)
Here first we store form in reg variable then also we write reg = StudentForm(request.POST) why?
acutally why we write this?
I can't tell you why you are writing this. Maybe only you know. It does not make much sense. I would recommend reading the Django documentation on this at https://docs.djangoproject.com/en/4.0/topics/forms/#the-view
from django.http import HttpResponseRedirect
from django.shortcuts import render
from .forms import NameForm
def get_name(request):
# if this is a POST request we need to process the form data
if request.method == 'POST':
# create a form instance and populate it with data from the request:
form = NameForm(request.POST)
# check whether it's valid:
if form.is_valid():
# process the data in form.cleaned_data as required
# ...
# redirect to a new URL:
return HttpResponseRedirect('/thanks/')
# if a GET (or any other method) we'll create a blank form
else:
form = NameForm()
return render(request, 'name.html', {'form': form})
You read from data if the request is a POST. Otherwise, return an empty form.
You could think of the "request.POST" as a parameter passed onto the form in the view. This tells the view that the form mentioned has POST data from the form in name.html. Otherwise it is just an empty form.
I'm trying to write a simple IF statement on checking if a lastname in a database exists before a user hits the submit button to create a new record. Here is my code so far, I'm new to Django and Python so the help is appreciated.
I made a variable called lastname, the thought process here is when the user hits submit, it checks the database first before the commit to warn them with a popup if the lastname exists to prevent duplicate records. It would actually be really cool to have it when a person exits the field for it to run the script before they finish filling out the form to save time.
#views.py
from .models import StudentCheck
from django.shortcuts import render
from django.http import HttpResponse, Http404, HttpResponseRedirect
from forms.forms import NewStudentForm
def NewStudentFormCheckList (request):
if request.method == 'POST':
form = NewStudentForm(request.POST)
lastname = StudentCheck.lastname
if form.is_valid():
newstudent= form.save()
else:
form = NewStudentForm()
return render(request, 'forms/newstudentcheck_form.html', {'form': form})
Here is my test code to see if query is working correctly and i keep getting a error that the query set doesnt exists.
from .models import StudentCheck
from django.core.exceptions import ValidationError
from django.shortcuts import render
from django.http import HttpResponse, Http404, HttpResponseRedirect
from forms.forms import NewStudentForm
def NewStudentFormCheckList (request):
if request.method == 'POST':
form = NewStudentForm(request.POST)
lastname = StudentCheck.lastname
number_lastnames = StudentCheck.objects.get(lastname__exact=lastname)
if form.is_valid():
newstudent= form.save()
print (number_lastnames)
else:
form = NewStudentForm()
return render(request, 'forms/newstudentcheck_form.html', {'form': form})
You can get all the entries in the database which have a given value already set using the field lookup exact (see here for more informations).
In your case it'll be StudentCheck.objects.get(lastname__exact=yourvalue). This would give you a QuerySet, and if you want to know how many entries have the given last name, you have to use count() on this QuerySet to know how many entries it has.
You can use this solutions in two different places:
Directly in the view, when receiving the POST values.
In a custom validator, which would be used in the definition of the model (see here to know how to do)
I would recommend to use the second one, as it would be easier to provide custom information for the user on why it's data where not accepted.
Both of these methods requires the data to be passed to the server to be validated though. Otherwise you can define a view that would receive the lastname and return if it's present already in the database in some way (JSON for example), which would be called using Ajax when the user click on the submit button.
Edit:
As per request of OP, here's an example of the custom validator:
from django.core.exceptions import ValidationError
from .models import StudentCheck
def validate_lastname(value):
number_lastnames = StudentCheck.objects.get(lastname__exact=value)
if number_lastnames > 0:
raise ValidationError(
'%s already exists' % value,
)
Now you can use this custom validator with attribute validators, either in the definition of your model or inside the definition of your form like this: lastname = models.CharField(validators=[validate_lastname]).
Hope it helps!
I have a form, "results", where one of the fields, "subjectID", is many-to-many because there's more than one result for each subject. I want one of the submit buttons to let me save what I've entered, then redirect to the same form, now unbound except that the many-to-many "subjectID" field stays the same so I can enter more results for that subject.
Edit: I should have made it clear that I wanted the instance that I had selected in the subjectID field to stay the same. I posted the code below that actually seems to be working for me
from models.py
class ResultsForm(forms.Modelform):
class Meta:
model = models.Results
fields = ['subjectID', # this is the field want
# to populate the form with when I "save and add another"
'slideNum', # IntegerField
'resultType' ] # ForeignKey
from views.py
def addResults(request):
if request.method == 'POST'
form = ResultsForm(request.POST)
if form.is_valid():
form.save()
if 'Save_and_add_another' in request.POST:
subjectID = form.fields['subjectID']
prepop = {'subjectID' : subjectID}
form = ResultsForm(initial=prepop)
return render(request, 'slideAdmin/addResults.html', {'form': form})
elif 'Save_and_return' in request.POST:
return HttpResponseRedirect('/home/')
else:
form = ResultsForm()
return render(request, 'slideAdmin/addResults.html', {'form': form})
Right now when I click on "save and add another" from my addResults form, I get this error:
TypeError at /slidebox/addResults
'ModelMultipleChoiceField' object is not iterable
which happens when rendering {{ form.as_p }} in the template.
Edit: Changes I made to views.py
if 'Save_and_add_another' in request.POST:
subjectID = form.cleaned_data.get('subjectID')
form = ResultsForm(initial={'subjectID': subjectID})
return render(request, 'slideAdmin/addResults.html', {'form': form})
As far as I can tell, this change works. Thanks again
You should always use form.cleaned_data.get('subjectID') versus pulling the field directly from the post data. You need to pass in a list of the pk's for the M2M field.
Your view can also use a touch of cleanup:
from django.core.urlresolvers import reverse
def addResults(request):
form = ResultsForm(request.POST or None)
if request.method == 'POST' and form.is_valid():
form.save()
if 'Save_and_add_another' in request.POST:
subjectID = form.cleaned_data.get('subjectID', [])
if subjectID:
subjectID = subjectIDs.split(',')
form = ResultsForm(initial={'subjectID': subjectID})
elif 'Save_and_return' in request.POST:
return HttpResponseRedirect(reverse('home')) # don't hard code
return render(request, 'slideAdmin/addResults.html', {'form': form})
I'm not sure if you will be able to keep the form unbound when initialized.
Your form.fields is an ordered dict of django.forms.fields objects. You just want the ids, and not all the other info that comes across it.
Get the data straight from the POST dictionary.
subjectID = request.POST.get('subjectID', '')
If this is a true many to many model. You need to make sure the data is setup correctly for the initialization.
# We have to special-case M2Ms as a list of comma-separated PKs.
if isinstance(f, models.ManyToManyField):
initial[k] = initial[k].split(",")
Here is the initialization method from the django source code for Admin (or as I call it my super detailed and complicated Django cheat sheet, I am pedantic)
def get_changeform_initial_data(self, request):
"""
Get the initial form data.
Unless overridden, this populates from the GET params.
"""
initial = dict(request.GET.items())
for k in initial:
try:
f = self.model._meta.get_field(k)
except FieldDoesNotExist:
continue
# We have to special-case M2Ms as a list of comma-separated PKs.
if isinstance(f, models.ManyToManyField):
initial[k] = initial[k].split(",")
return initial
Some PEP8 nonsense as well
classes are camel case ex: class MyAwesomeClass(object):
everything else is lower with underscores. ex: awesome_id = awesome1245
Good Luck!!
I have created a website for user registration with first name, last name, phone no and so on.
I have successfully established a connection to MySQL database. I want help regarding IntegrityError handling in django,since I'm a newbie.
When 2 users input same phone number, django takes me to its debug page with whole lots of information. Instead I want to notify the user then and there that another user with same phone number already exists. Please provide any pointers on this.
Following is my views.py file in which I process the form:
from django.shortcuts import render
from formProcessing.forms import UserForm
def form(request):
#This is using regular Django forms
#print request.POST
#form = EmailForm(request.POST or None)
#This is using model forms
form = UserForm(request.POST or None)
if form.is_valid():
new_instance = form.save(commit=True)
new_instance.save()
context = {"form": form }
template = "form.html"
return render(request,template,context)
In your UserForm you can overwrite clean method of your number attribute, lets say that your attribute is called 'number'
class UserForm(ModelForm):
#your user form attributes and stuff
def clean_number(self, value):
user_number = value
number_occurrences = User.objects.filter(number=user_number).count()
if number_occurrences > 0:
raise forms.ValidationError("You number is already taken by other user")
return self.cleaned_data
Check django docs about form validation
If you dont wan't to overwrite clean method and do it whitin your view. you can. (Is not elegant)
def form(request):
#This is using regular Django forms
#print request.POST
#form = EmailForm(request.POST or None)
#This is using model forms
number = request.POST.get('telephone')
number_occurrences = User.objects.filter(number=user_number).count()
if number_occurrences > 0:
context = {'error':'Number already exist'}
return render(request,template,context)
form = UserForm(request.POST or None)
if form.is_valid():
new_instance = form.save(commit=True)
new_instance.save()
context = {"form": form }
template = "form.html"
return render(request,template,context)
Before you create an object, query the db for the existence of that phone number.
if form.is_valid():
ph_number = #"Phone number from form"
if User.objects.filter(phone_number = ph_number).first():
return HttpResponse("The number already exists.")
new_instance = form.save(commit=True)
new_instance.save()
The first() method returns the index 0 of the queryset. So, if there is element 0 in the queryset, the error message will be displayed to the user.
you can probably do something with field validation, although I don´t know exactly what your error is, or how the model is designed.
Anyway, you could try to look up whether the value is unique (i.e., look if another record exists with the same number), before trying to save it; this might be the cleanest.
https://docs.djangoproject.com/en/1.7/ref/forms/validation/#cleaning-a-specific-field-attribute
so something like:
def clean_telephone(self):
n = User.objects.filter(telephone=self.cleaned_data['telephone']).count()
if n > 0:
raise forms.ValidationError("telephone number is already in database")
return data
Or you could try to save it and catch the unique error with a try/except clause. This uses less databases access attempts.
I know how to set initial values to a form from the view. But how do I go about letting a generic view set initial values to a form? I can write a wrapper view for the generic view, but I still have no access to the form object instantiation.
The specific goal I'm trying to achieve is to have a user create a new object, using the create_object generic view. However, I'd like to set a field of the object 'user' to the currently logged in user, which is only accessible as request.user. How can the form be initialized to have this field?
Edit: I came across __new__. Could this call its own constructor with some default arguments?
Many thanks.
Unfortunately, you cannot achieve this behavior through Django's create_object generic view; you will have to write your own. However, this is rather simple.
To start off, you must create a new form class, like this:
from django import forms
class MyForm(forms.ModelForm):
class Meta:
model = MyModel # model has a user field
Then you would be able to create a view like this:
from django.shortcuts import render_to_response
from django.template import RequestContext
from django.http import HttpResponseRedirect
from django.contrib.auth.decorators import login_required
#login_required
def create_mymodel(request):
if request.method == 'POST':
# Get data from form
form = MyForm(request.POST)
# If the form is valid, create a new object and redirect to it.
if form.is_valid():
newObject = form.save()
return HttpResponseRedirect(newObject.get_absolute_url())
else:
# Fill in the field with the current user by default
form = MyForm(initial={'user': request.user})
# Render our template
return render_to_response('path/to/template.html',
{'form': form},
context_instance=RequestContext(request))
You could do this in a generic view wrapper by dynamically constructing a form class and passing it to the generic view, but that cure is probably worse than the disease. Just write your own view, and wait eagerly for this to land.
If you want all the features of the generic view then you can just create a new generic view using the original as a template.
Eg:
def create_object_with_initial(request, model=None, template_name=None,
template_loader=loader, extra_context=None, post_save_redirect=None,
login_required=False, context_processors=None, form_class=None, initial=None):
if extra_context is None: extra_context = {}
if login_required and not request.user.is_authenticated():
return redirect_to_login(request.path)
model, form_class = get_model_and_form_class(model, form_class)
if request.method == 'POST':
form = form_class(request.POST, request.FILES)
if form.is_valid():
new_object = form.save()
msg = ugettext("The %(verbose_name)s was created successfully.") %\
{"verbose_name": model._meta.verbose_name}
messages.success(request, msg, fail_silently=True)
return redirect(post_save_redirect, new_object)
else:
print "creating", form_class, " with initial data ", initial
form = form_class(initial=initial)
# Create the template, context, response
if not template_name:
template_name = "%s/%s_form.html" % (model._meta.app_label, model._meta.object_name.lower())
t = template_loader.get_template(template_name)
c = RequestContext(request, {
'form': form,
}, context_processors)
apply_extra_context(extra_context, c)
return HttpResponse(t.render(c))
This is copied from /site-packages/django/views/generic/create_update.py with only lines 3 and 21 changing to incorporate the initial data.
Then use it as you might expect:
object_info = {
'model': YourModel,
'initial': {'data' : 'Initial Value'},
'template_name': 'template.html'
}
url(r'^path/$',
login_required(create_object_with_initial),
object_info,
name='url_name'),
That should work.