reverse() argument after ** must be a mapping

Question

I have an inscription form that doesn't work when submitting.

I get this error:

reverse() argument after ** must be a mapping, not str**

This is my view:

def inscription(request, seance_id):
    seance = get_object_or_404(Variant, id=seance_id)
    inscription_config = {'form_class': InscriptionForm,
                          'extra_context': {'seance': seance}}    

    return create_object(request, **inscription_config)

My form:

class InscriptionForm(forms.ModelForm):
    class Meta:
        model = Inscription
        
    def clean(self):
        cleaned_data = self.cleaned_data
        email = cleaned_data.get("mail")
        mail_confirmation = cleaned_data.get("mail_confirmation")
    
        if email != mail_confirmation:
            raise forms.ValidationError("Les deux adresses mails doivent correspondre")
    
        return cleaned_data

Seems what triggering the error is inscription_config in the return statement, but I have no idea why.

EDIT

Environment:

Request Method: POST Request URL: http://127.0.0.1:8039/formations/inscription/1/ Django Version: 1.2.5 Python Version: 2.7.2 Installed Applications: ['django.contrib.auth', 'django.contrib.comments', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'django.contrib.messages', 'django.contrib.admin', 'ckeditor', 'constance', 'constance.backends.database', 'custom_flatpages', 'django_extensions', 'django_mobile', 'django_xmlrpc', 'easy_thumbnails', 'gestion_formations', 'file_uploader', 'less', 'mptt', 'contact', 'newsletter', 'pagination', 'south', 'sentry', 'sentry.client', 'indexer', 'paging', 'contentadmin', 'gallerie'] Installed Middleware: ('annoying.middlewares.StaticServe', 'django.middleware.common.CommonMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.csrf.CsrfViewMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'django.contrib.messages.middleware.MessageMiddleware', 'pagination.middleware.PaginationMiddleware')

Traceback:

File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py" in get_response 100. response = callback(request, callback_args, **callback_kwargs) File "/home/anass/projects/c139_fc_finance/fc_finance/gestion_formations/views/carts.py" in inscription 24. form_class= InscriptionForm File "/usr/local/lib/python2.7/dist-packages/django/views/generic/create_update.py" in create_object 118. return redirect(post_save_redirect, new_object) File "/usr/local/lib/python2.7/dist-packages/django/views/generic/create_update.py" in redirect 65. return HttpResponseRedirect(obj.get_absolute_url()) File "/usr/local/lib/python2.7/dist-packages/django/utils/functional.py" in _curried 55. return _curried_func((args+moreargs), **dict(kwargs, **morekwargs)) File "/usr/local/lib/python2.7/dist-packages/django/db/models/base.py" in get_absolute_url 969. return settings.ABSOLUTE_URL_OVERRIDES.get('%s.%s' % (opts.app_label, opts.module_name), func)(self, *args, **kwargs) File "/usr/local/lib/python2.7/dist-packages/django/db/models/init.py" in inner 32. return reverse(bits[0], None, *bits[1:3]) File "/usr/local/lib/python2.7/dist-packages/django/core/urlresolvers.py" in reverse 351. *args, **kwargs)))

Exception Type: TypeError at /formations/inscription/1/ Exception Value: reverse() argument after ** must be a mapping, not str

Please provide the entire traceback. The code you show here doesn't look like it will cause the error you are talking about. — Ned Batchelder, Mar 26 '13 at 16:47
This sounds a lot more like the issue is in your urls.py or something like that. Second what Ned said about full traceback. — Colleen, Mar 26 '13 at 16:49
@Colleen here is my url : `url(r'^inscription/(?P\d+)/$', inscription, name='inscription'), ` — Armance, Mar 26 '13 at 16:52
Where is the code with the `form_class= InscriptionForm` line? — Martijn Pieters, Mar 26 '13 at 16:56
It's in the view ,this variable : `inscription_config = {'form_class': InscriptionForm, 'extra_context': {'seance': seance}} ` — Armance, Mar 26 '13 at 16:57
This appears to be a problem with your `get_absolute_url` method. You should post that. — Daniel Roseman, Mar 26 '13 at 17:09
@DanielRoseman If you can write an answer so I can accept it, and maybe explain how did you know the error came from get_absolute_url — Armance, Mar 26 '13 at 18:11
I've got a similar issue happening - what was the problem, and how was it solved? — Lexo, Oct 16 '13 at 21:36

FSp · Accepted Answer · 2014-09-10T06:39:55.697

I try to answer, since I had the same problem but didn't find an answer online.

I think the origin of this problem is a wrong get_absolute_url(...) method. For example, if you write it like this:

@models.permalink
def get_absolute_url(self):
    return reverse('my_named_url', kwargs={ "pk": self.pk })

Then it raises the exception reverse() argument after ** must be a mapping, not str. Fix it removing the @models.permalink decorator, as follows:

def get_absolute_url(self):
    return reverse('my_named_url', kwargs={ "pk": self.pk })

or alternatively keep the decorator and modify the body, as follows:

@models.permalink
def get_absolute_url(self):
    return ('my_named_url', (), { "pk": self.pk })

I think that the latter is deprecated, though.

In my code **return reverse('article-detail', kwargs=({'pk': self.post.pk}))** — AnonymousUser, Sep 09 '21 at 06:33

score 2 · Answer 2 · answered Dec 11 '21 at 06:30

2

Naughty comma

return redirect(reverse_lazy('team-detail', kwargs={'pk', team.pk}))

it should be

return redirect(reverse_lazy('team-detail', kwargs={'pk': team.pk}))

answered Dec 11 '21 at 06:30

Weilory

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Oops, I did it again. – voneiden Jan 21 '22 at 12:41

reverse() argument after ** must be a mapping

2 Answers2