CODEWITHSUNDEEP
djangodictionarypostrequest
TJB
TJB

Reputation: 3856

Difficulty converting request.POST value in Django

In my Django application, I have a POST request QueryDict whose values I am trying to change. I understand that QueryDict objects are immutable, so I instantiated a QueryDict item that is mutable. The crux of the problem is that the value is a byte string of comma separated numbers coming in from a AJAX call in the front end of the application, e.g. U"2,4,6,7".

Each key value in a QueryDict is inherently a list of values, [U'2', U'4'] so I need to change the single byte U"2,4,6,7" posted from my front end into a list of byte strings [U'2', U'4', U'6', '7']. The problem however is whenever I try to do a split on the string and assign the request POST key value to that new split string, the key value is a list, in a list. e.g. {'expertise': [[U'2', U'4']]}. I tried a contrived solution by iterating through a split list of the values, and appending them into the key value of the request POST item, but it gives me the error 

AttributeError: 'unicode' object has no attribute 'append'

In a mutable QueryDict object, if each QueryDict item is a list, and it has no value append, than how is it possible to edit the list item ? Is there a simpler way of accomplishing this ?

View Function Code

mentors = Mentor.objects.filter(is_active=True, is_verified=True).order_by('last_name', 'first_name')

ajax_post = dict(request.POST.iteritems())

post = QueryDict('', mutable=True)
post.update(ajax_post)

for key in post:
    postlist = post[key].split(',')

    for item in postlist:
        post[key].append(item)

# First attempt that gives list in a list

# for item in post:
#    post[key] = post[key].split(',')

form = MentorSearchForm(data=post)

if form.is_valid():
    mentors = filter_mentors(form.cleaned_data)

Upvotes: 0

Views: 1354

Answers (2)

Alasdair
Alasdair

Reputation: 309089

You're getting caught out by the QueryDict.__setitem__. When you do querydict['key'] = value, it sets the key to [value], not value.

You can use the QueryDict.setlist method to set the given key to the given list.

querydict = QueryDict('', mutable=True)

for key in request.POST.iteritems():
    postlist = post[key].split(',')
    querydict.setlist(key, postlist)

Since you are going to loop through every key in the post data, I think you can remove the update() step from your code.

Upvotes: 3

marmeladze
marmeladze

Reputation: 6572

If I've understood the constraints correctly, you should use builtin array type.

>>> q =  U"2,4,6,7"
>>> import array
>>> ary = array.array('u', q)
>>> [i for i in ary if i.isdigit()]
[u'2', u'4', u'6', u'7']

Upvotes: 1

Related Questions