Bug DynamicFormMixin class does not commit ResponseModel Foreign Key properly

[manojgudi]

Firstly, thanks for creating this package @askvortsov1 , its been v useful! I've been following the example included in the source code, the docker file works well, however in my own implementation which is very similar I get a strange django.db.utils.IntegrityError when I try to save response to a dynamic form. Here's the gist of my models:

from django.db import models

# Create your models here.
from django.db import models
from dynamic_forms.models import FormField, ResponseField
from authentication.models import Organization

class DynamicFormModel(models.Model):
    name         = models.CharField(max_length=100)
    organization = models.ForeignKey(Organization, on_delete=models.CASCADE, null=True)
    form         = FormField()

    def __str__(self):
        return "Dynamic Form #{}:{}".format(self.pk, self.name)

class DynamicFormResponseModel(models.Model):
    dynamicForm = models.ForeignKey(DynamicFormModel, on_delete=models.CASCADE)
    response    = ResponseField()

Here's the stack trace

Environment:

Request Method: POST
Request URL: http://127.0.0.1:8000/dynamicforms/dynamic-forms/1/response/

Django Version: 3.1.3
Python Version: 3.6.9
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'dynamicforms',
 'authentication',
 'dynamic_forms',
 'crispy_forms']
Installed Middleware:
('whitenoise.middleware.WhiteNoiseMiddleware',
 'django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware')

Traceback (most recent call last):
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)

The above exception (null value in column "dynamicForm_id" of relation "dynamicforms_dynamicformresponsemodel" violates not-null constraint
DETAIL:  Failing row contains (21, {"Are you a piece of shit<br>": "option-certainly", "My role is ..., null).
) was the direct cause of the following exception:
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/core/handlers/base.py", line 179, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/views/generic/base.py", line 70, in view
    return self.dispatch(request, *args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/views/generic/base.py", line 98, in dispatch
    return handler(request, *args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/utils/decorators.py", line 43, in _wrapper
    return bound_method(*args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/utils/decorators.py", line 130, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/views/generic/edit.py", line 172, in post
    return super().post(request, *args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/views/generic/edit.py", line 142, in post
    return self.form_valid(form)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/dynamic_forms/views.py", line 31, in form_valid
    action.save()
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/base.py", line 754, in save
    force_update=force_update, update_fields=update_fields)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/base.py", line 792, in save_base
    force_update, using, update_fields,
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/base.py", line 895, in _save_table
    results = self._do_insert(cls._base_manager, using, fields, returning_fields, raw)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/base.py", line 935, in _do_insert
    using=using, raw=raw,
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/manager.py", line 85, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/query.py", line 1254, in _insert
    return query.get_compiler(using=using).execute_sql(returning_fields)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/models/sql/compiler.py", line 1397, in execute_sql
    cursor.execute(sql, params)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 98, in execute
    return super().execute(sql, params)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 66, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 75, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/utils.py", line 90, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/johnathon/projects/acs/lib/python3.6/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)

Exception Type: IntegrityError at /dynamicforms/dynamic-forms/1/response/
Exception Value: null value in column "dynamicForm_id" of relation "dynamicforms_dynamicformresponsemodel" violates not-null constraint
DETAIL:  Failing row contains (21, {"Are you a person<br>": "option-certainly", "My role is ..., null).

I was able to fix this by changing the definition of DynamicFormMixin class, here's the diff:

@@ -16,6 +16,7 @@
         form = super().get_form(*args, **kwargs)
         # Get instance of model containing form used for this response. Save this object as an instance variable for use in form_valid method
         form_instance_pk = self.kwargs[self.form_pk_url_kwarg]
+        self.form_instance_pk = form_instance_pk
         self.form_instance = self._get_object_containing_form(form_instance_pk)
         # Get json form configuration from form-containing object
         json_data = getattr(self.form_instance, self.form_field)
@@ -26,6 +27,7 @@
     def form_valid(self, form):
         action = form.save(commit=False)
         action.survey = self.form_instance
+        setattr(action, self.form_pk_url_kwarg, self.form_instance_pk)
         action.save()
         return super().form_valid(form)

Am I missing something? Is this a bug? If yes, would be happy to help you a PR, let me know, thanks!

[askvortsov1]

Looks like I hardcoded the response fk field as survey for some reason, and to top it off, all my local usage overrides form_valid so the issue didn't occur for me. Brilliant :see_no_evil:.

I've released a new version, could you check if that works better?

[askvortsov1]

Closing as should be fixed. Feel free to reopen if you're still running into issues.