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Is it possible to use request.POST as a dictionary input?

In my django project, I collect membership data by HTML form and insert them into the database. There are the code samples:
models.py
class member(models.Model):
name = models.CharField(max_length=100,blank=True,null=True)
gender = models.CharField(max_length=10,blank=True,null=True)
profession = models.CharField(max_length=100,blank=True,null=True)
views.py:
def manage(request):
form_values = request.POST.copy()
form_values.pop('csrfmiddlewaretoken') # I don't need it.
add_member = member(**form_values)
add_member.save()
If HTML form input is: Rafi, Male, student
Database gets in list format: ['Rafi'], ['Male'], ['student']
How can I solve this?

You can make use of the .dict() [Django-doc] method here:
def manage(request):
form_values = request.POST.copy()
form_values.pop('csrfmiddlewaretoken')
add_member = member(**form_values.dict())
add_member.save()
If there are multiple values for the same key, it will take the last one.
That being said, it might be better to take a look at a ModelForm [Django-doc] to validate data and convert it to a model object. This basically does what you do here, except with proper validation, removing boilerplate code, and furthermore it will not use the other keys. If here a user would "forge" a POST request with extra key-value pairs, the server will raise a 500 error.

using a ModelForm to sanitize post data in Django

I've come across How to create object from QueryDict in django? , which answers what I want to do. However I want to sanitize the data. What does the Brandon mean by "using a ModelForm" to sanitize posted data?

ModelForm are very helpful when you want to create just model instances. If you create a form that closely looks like a model then you should go for a model form instead. Here is an example.
Going by the example provided in the Django website.
In your forms.py
class ArticleForm(ModelForm):
class Meta:
model = Articels #You need to mention the model name for which you want to create the form
fields = ['content', 'headline'] #Fields you want your form to display
So in the form itself you can sanitize your data as well. There are 2 ways of doing that.
Way 1: Using the clean function provided by Django using which you can sanitize all your fields in one function.
class ArticleForm(ModelForm):
class Meta:
model = Articels #You need to mention the model name for which you want to create the form
fields = ['content', 'headline'] #Fields you want your form to display
def clean(self):
# Put your logic here to clean data
Way 2: Using clean_fieldname function using which you can clean your form data for each field separately.
class ArticleForm(ModelForm):
class Meta:
model = Articels #You need to mention the model name for which you want to create the form
fields = ['content', 'headline'] #Fields you want your form to display
def clean_content(self):
# Put your logic here to clean content
def clean_headline(self):
# Put your logic here to clean headline
Basically you would use clean and clean_fieldname methods to validate your form. This is done to raise any error in forms if a wrong input is submitted. Let's assume you want the article's content to have at least 10 characters. You would add this constraint to clean_content.
class ArticleForm(ModelForm):
class Meta:
model = Articels #You need to mention the model name for which you want to create the form
fields = ['content', 'headline'] #Fields you want your form to display
def clean_content(self):
# Get the value entered by user using cleaned_data dictionary
data_content = self.cleaned_data.get('content')
# Raise error if length of content is less than 10
if len(data_content) < 10:
raise forms.ValidationError("Content should be min. 10 characters long")
return data_content
So here's the flow:
Step 1: User open the page say /home/, and you show the user a form to add new article.
Step 2: User submits the form (content length is less than 10).
Step 3: You create an instance of the form using the POST data. Like this form = ArticleForm(request.POST).
Step 4: Now you call the is_valid method on the form to check if its valid.
Step 5: Now the clean_content comes in play. When you call is_valid, it will check if the content entered by user is min. 10 characters or not. If not it will raise an error.
This is how you can validate your form.

What he mean is that with ModelForm you can not only create model instance from QueryDict, but also do a bunch of validation on data types and it's requirements as for example if value's length correct, if it's required etc. Also you will pass only needed data from QueryDict to model instance and not whole request
So typical flow for this is:
form = ModelForm(request.POST)
if form.is_valid():
form.save()
return HttpResponse('blah-blah success message')
else:
form = ModelForm()
return HttpResponse('blah-blah error message')
And awesome Django docs for this: https://docs.djangoproject.com/en/dev/topics/forms/modelforms/#django.forms.ModelForm

Django form returns is_valid() = False and no errors

I have simple view in django app, which I want to show only when one of the forms is valid. I have something like:
#login_required
#require_role('admin')
def new_package(request):
invoicing_data_form = InvoicingDataForm(instance=request.user.account.company.invoicingdata)
if invoicing_data_form.is_valid():
# all here
return HttpResponse('Form valid')
else:
logger.info("Form invalid")
return HttpResponse(json.dumps(invoicing_data_form.errors)
I always get log info message that form is invalid, however, I get nothing in
invoicing_data_form.errors
It is very strange, because I am validating this form in other view using user input data and it works just fine. Any idea?
EDIT:
Just for clarification.
I am not requesting any data from user in this form.
I am using this form to validate some model instance (this form is subclassing from ModelForm).

That's because you're not "feeding" your form.
Do this:
invoicing_data_form = InvoicingDataForm(instance=invoice, data=request.POST or None)

You have an unbound form.
https://docs.djangoproject.com/en/1.7/ref/forms/api/#bound-and-unbound-forms
A Form instance is either bound to a set of data, or unbound.
If it’s bound to a set of data, it’s capable of validating that data and rendering the form as HTML with the data displayed in the HTML.
If it’s unbound, it cannot do validation (because there’s no data to validate!), but it can still render the blank form as HTML.
To bind data to a form, pass the data as a dictionary as the first parameter to your Form class constructor:
invoicing_data_form = InvoicingDataForm(request.POST or None, instance=invoice)

If you're already giving request.POST to your form using request.POST or None, but it's still invalid without errors, check that there isn't any redirect going on. A redirect loses your POST data and your form will be invalid with no errors because it's unbound.

I got this for AuthenticationForm which needs AuthenticationForm(None, request.POST) see Using AuthenticationForm in Django

I want to expand on the answer by #yuji-tomita-tomita
I typically use a CBV approach in Django, and how I'm handling forms:
def post(self, request, *args, **kwargs):
form = self.get_form()
if form.is_valid():
# do things
Reading the source code I noticed that self.get_form() using get_form_kwargs(self) to populate the form with request.POST, thus getting bound to data. So if you're overloading it like I did:
def get_form_kwargs(self):
company = self.get_company()
return {"company": company}
Make sure to call the super(), and it will finally work:
def get_form_kwargs(self):
company = self.get_company()
kwargs = super().get_form_kwargs()
kwargs.update({"company": company})
return kwargs

Django: How do I access post data and match with a criteria

I need some guidance on best practice implementation of the following.
I have a scenario where I am building an app, but if it matches a certain "category" or "locale" and want to redirect it to a page in between else just go the normal route.
Here is my simple views.py
if form.is_valid():
...
kwargs = {'project_id':project_id, 'categories':request.POST['categories'], 'locale':request.POST['locale']}
process_se(request, **kwargs)
return HttpResponseRedirect(obj.next_url)
Here is what I have in my models.py file but it seems to be very inconsistent.
Is there a better way to handle this request?
def process_se(self, request, **kwargs):
if "All" or "Sweden" in kwargs['locale']:
if "Technology" or "Internet" in kwargs['categories']:
next_url = request.build_absolute_uri(reverse('project_new_se', kwargs={'project_id': self.id}))
else:
next_url = request.build_absolute_uri(reverse('project_new_step2', kwargs={'project_id': self.id}))
self.next_url = next_url
UPDATES:
I am using forms.ModelForm, categories and locales are ManyToManyField's
I have simulated a for in the shell and still seem to get no result
Here is the cleaned_data output
f.cleaned_data
{'locale': [<Locale: Sweden>, <Locale: All>], 'categories': [<Category: Technology>, <Category: Internet>]}
Although running this for fields in the form seem to render perfectly fine based on your solution

I originally proposed putting this code in the form class, but ApPeL revised the question to point out that locale and categories are many-to-many fields on the model. So now I suggest putting a method like this in your model:
def requires_swedish_setup(self):
"""
Return True if this project requires extra Swedish setup.
"""
return (self.locale.filter(name__in = ('All', 'Sweden')).exists())
and self.categories.filter(name__in = ('Technology', 'Internet')).exists())
and then implementing your view like this:
if form.is_valid():
project = form.save()
next = 'project_new_step2'
if project.requires_swedish_setup():
next = 'project_new_se'
next_url = reverse(next, kwargs={'project_id': project.id})
return HttpResponseRedirect(next_url)
Some notes:
I'm assuming that Locale and Category objects have name fields (if not, use whatever field contains the name you are testing).
It's not a good idea to read form data out of request.POST (widgets haven't had a chance to run, and it hasn't been validated): it's better to use form.cleaned_data.
You don't need to call request.build_absolute_uri in this case: it's fine to feed the result of reverse directly to HttpResponseRedirect.
"All" or "Sweden" in kwargs['locale'] is probably not what you mean: it parses like "All" or ("Sweden" in kwargs['locale']) and so is always true.

django ModelForm save() method issue

I have a model form:
class SnippetForm(ModelForm):
class Meta:
model = Snippet
exclude = ['author', 'slug']
and I want to be able to edit a particular instance by using this:
def edit_snippet(request, snippet_id):
#look up for that snippet
snippet = get_object_or_404(Snippet, pk=snippet_id)
if request.user.id != snippet.author.id:
return HttpResponseForbidden()
if request.method == 'POST':
form = SnippetForm(data=request.POST, instance=snippet)
if form.is_valid():
form.save()
return HttpResponseRedirect(snippet.get_absolute_url())
else:
form = SnippetForm(instance=snippet)
return render_to_response(SNIPPET_EDIT_TEMPLATE,
{'form':form, 'add':False, 'user':request.user},
RequestContext(request))
Notice that at the line
form = SnippetForm(data=request.POST, instance=snippet)
, I created a form that use the data supplied from the user, and bound it with the instance found using the primary key (received from the url). According to django documentation, when I call save() the existing instance should be updated with POSTED data. Instead, what I see is a new object is created and saved into the database. What went wrong? Thanks a lot.
[Edit] This is really embarrassed. The code indeed has nothing wrong with it. The only thing that messed up the whole thing was the action I put in the template (as I use a same template for add and edit a snippet)....Thanks a lot for your help, really appreciate that.

I don't see why it would happen. What version of django is it?
In any case, you can manually force update passing the corresponding argument.
form = SnippetForm(data=request.POST, instance=snippet, force_update=True)