Django form: what is the best way to modify published data before validation?

Question

form = ContactForm(request.POST)

# how to change form fields' values here?

if form.is_valid():
    message = form.cleaned_data['message']

Is there a good way to trim spaces, change some / all fields, etc. before checking the data?

Answer 1

You should make request.POST (instance QueryDict) change by calling copyon it, and then change the values:

post = request.POST.copy() # to make it mutable
post['field'] = value
# or set several values from dict
post.update({'postvar': 'some_value', 'var': 'value'})
# or set list
post.setlist('list_var', ['some_value', 'other_value']))

# and update original POST in the end
request.POST = post

QueryDictdocs - Request and response objects

Answer 2

You can also try using request.query_params.

• First, set _mutablethe value of query_paramsvalue True.

• Change all the necessary parameters.

  request.query_params._mutable = True
  request.quer_params['foo'] = 'foo'
  

, request.POST.copy().