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django import-export how to add foreign key

I am using django-import-export to import an excel to my model, what I do is that I create a form with some inputs from where it loads the file, then in form_valid() I process the file to load it to the database, the model has two foreign keys 'id_order' and 'gestion'; 'id_orden' comes in the excel and 'gestion' I get it with gestion= Gestion.objects.get(idgestion=obj.pk) which is the id of the form that I am saving, but what I want to know is how I can pass 'gestion' to ModelResource and then save it to the database
view.py
class GestionView(CreateView):
model = Gestion
form_class = GestionForm
template_name = 'asignacion/gestion.html'
success_url = reverse_lazy('asignacion_url:gestion')
def form_valid(self, form):
isvalid = super().form_valid(form)
obj = form.save()
gestion= Gestion.objects.get(idgestion=obj.pk)
file = self.request.FILES['file']
item_gestion =ItemResourceResource()
dataset = Dataset()
imported_data = dataset.load(file.read(), format='xls')
result = item_gestion.import_data(dataset, dry_run=True)
if not result.has_errors():
item_gestion.import_data(dataset, dry_run=False)
model.py
class ItemGestion(models.Model):
idgestion = models.AutoField(primary_key=True)
numero_imagenes = models.CharField(max_length=45, blank=True, null=True)
id_orden = models.ForeignKey('Asignacion', models.DO_NOTHING)
aviso_sap = models.CharField(max_length=45, blank=True, null=True)
poliza = models.CharField(max_length=45, blank=True, null=True)
observacion_cierre = models.CharField(max_length=250, blank=True, null=True)
gestion=models.ForeignKey('Gestion', models.DO_NOTHING)
resources.py
class ItemResourceResource(resources.ModelResource):
id_orden = fields.Field(column_name='id_orden', attribute='id_orden',
widget=ForeignKeyWidget(Asignacion,'id_orden'))
class Meta:
model = ItemGestion
import_id_fields = ('id_orden',)
exclude = ('idgestion', )

It is easy to do. You need to pass the gestion value into your Resource, and then link it to the instance before it is persisted:
class ItemResourceResource(ModelResource):
def __init__(self, gestion):
self.gestion = gestion
def before_save_instance(self, instance, using_transactions, dry_run):
instance.gestion = self.gestion
class Meta:
# ...
gestion = Gestion.objects.get(idgestion=obj.pk)
item_gestion = ItemResourceResource(gestion)
Obviously this means that all the instances created from the rows in your dataset will be linked to the same 'gestion' value.
btw import-export integrates with django-admin, so you can use the admin interface to import data rather than writing your own forms (if that fits your requirements). See the docs for more information.

Posting to multiply related tables Django

I would like to create my own endpoint for POST request to two related tables. I have two tables User and Userattribute.
models.py
class User(models.Model):
email = models.CharField(unique=True, max_length=180)
roles = models.JSONField(default=dict)
password = models.CharField(max_length=255, blank=True, null=True)
name = models.CharField(max_length=255, blank=True, null=True)
firebase_id = models.CharField(max_length=255, blank=True, null=True)
created_at = models.DateTimeField(default=now)
progress_sub_step = models.IntegerField(blank=True, null=True)
step_available_date = models.DateTimeField(blank=True, null=True)
progress_step = models.IntegerField(blank=True, null=True)
active = models.IntegerField(default=1)
last_login_at = models.DateTimeField(blank=True, null=True)
class Meta:
managed = False
db_table = 'user'
class Userattribute(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True, related_name = 'attribute')
attribute = models.ForeignKey(Attribute, on_delete=models.CASCADE)
The table Userattribute contains the field user which is OnetoOne to Id primary key from User table.
I tried to implement POST to two tables in serializers.py In the commented section there is a create definition which works perfectly for me. However, I wouldlike to move it to views.py as register_in_course endpoint
serializers.py
class FilmSerializer(serializers.ModelSerializer):
class Meta:
model = Film
fields = ['tytul', 'opis', 'po_premierze']
class UserattributeSerializer(serializers.ModelSerializer):
class Meta:
model = Userattribute
fields = ['user', 'attribute']
class UASerializer(serializers.ModelSerializer):
class Meta:
model = Userattribute
fields = ['attribute']
class UserSerializer(serializers.ModelSerializer):
attribute = UASerializer(many = False)
class Meta:
model = User
fields = ['email', 'name', 'firebase_id', 'attribute']
# This is what workks perfectly for me, and I want to move it to views.py
# VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV
# def create(self, validated_data):
# attribute_data = validated_data.pop('attribute')
# user = User.objects.create(**validated_data)
# Userattribute.objects.create(user=user, **attribute_data)
# return user
Current views.py:
class UserViewSet(viewsets.ModelViewSet):
queryset = User.objects.all()
serializer_class = UserSerializer
#action(detail = False, methods = ['post'])
def register_in_course(self, request, **kwargs):
data = self.get_object()
user = User.objects.create(email=request.data['email'],
name=request.data['name'],
firebase_id=request.data['firebase_id'])
user_id = User.objects.filter(firebase_id = request.data['firebase_id'])['id']
attribute = Userattribute.objects.create(user = user_id, attribute = request.data['attribute']['attribute'])
user = user.attribute.add(attribute)
serializer = UserSerializer(user, many = false)
return Response(serializer.data)
Using endpoint register_in_course to POST I get following error:
Expected view UserViewSet to be called with a URL keyword argument named "pk". Fix your URL conf, or set the .lookup_field attribute on the view correctly.
urls.py
from django.urls import include, path
from django.conf.urls import url
from rest_framework import routers
from api import views
router = routers.DefaultRouter()
router.register(r'users', views.UserViewSet)
router.register(r'userattribute', views.UserattributeViewSet)
urlpatterns = [
url('', include(router.urls))
]

i removed one line user_id variable and changed attribute variable. please check, maybe it should solve your problem, because you have already have Assigned variable as a User object..
class UserViewSet(viewsets.ModelViewSet):
queryset = User.objects.all()
serializer_class = UserSerializer
#action(detail = False, methods = ['post'])
def register_in_course(self, request, **kwargs):
data = self.get_object()
user = User.objects.create(email=request.data['email'],
name=request.data['name'],
firebase_id=request.data['firebase_id'])
attribute = Userattribute.objects.create(user = user, attribute = request.data['attribute']['attribute']) # changed this line
user = user.attribute.add(attribute)
serializer = UserSerializer(user, many = false)
return Response(serializer.data)

This issue is caused by calling get_object in a view that is defined with detail=False:
#action(detail = False, methods = ['post'])
def register_in_course(self, request, **kwargs):
data = self.get_object() # The problem is caused by this line
It seems you don't need this data, as you are using request.data.
So you can define your view like this:
#action(detail = False, methods = ['post'])
def register_in_course(self, request, **kwargs):
user = User.objects.create(
email=request.data['email'],
name=request.data['name'],
firebase_id=request.data['firebase_id']
)
Userattribute.objects.create(
user=user,
attribute = request.data.get('attribute', {}).get('attribute', {})
)
return Response(UserSerializer(user).data)

Getting this name error whilst using django-taggit: name 'Tag' is not defined

For my website, I want users to be able to add tags to their posts. But I get this error:
python name 'Tag' is not defined
Here is some code
Relevant code in models.py
from taggit.managers import TaggableManager
class Post(models.Model):
author = models.ForeignKey(User, on_delete=models.CASCADE)
title = models.CharField(max_length=75)
text = models.TextField()
created_date = models.DateTimeField(default=timezone.now)
image = models.ImageField(upload_to='post_images',blank=True,null=True)
published_date = models.DateTimeField(blank=True,null=True,auto_now_add=True)
NSFW = models.BooleanField(default=False)
spoiler = models.BooleanField(default=False)
tags = TaggableManager()
def __str__(self):
return self.title
def save(self, *args, **kwargs):
super().save(*args, **kwargs)
Here is the relevant code in views.py
class TagMixin(object):
def get_context_data(self,**kwargs):
context = super(TagMixin,self).get_context_data(**kwargs)
context['tags'] = Tag.objects.all()
return context
class PostListView(TagMixin,ListView):
template_name = 'mainapp/post_list.html'
model = Post
context_object_name = 'posts'
queryset = Post.objects.all()
def get_queryset(self):
return Post.objects.filter(published_date__lte=timezone.now()).order_by('-published_date')
class TagIndexView(TagMixin,ListView):
template_name = 'mainapp/post_list.html'
context_object_name = 'posts'
model = Post
def get_queryset(self):
return Posts.objects.filter(tags__slug=self.kwargs.get('slug'))
And here is the form.
class PostForm(forms.ModelForm):
class Meta():
model = Post
fields = ['title','text','image','tags','spoiler','NSFW']
widgets = {
'title':forms.TextInput(attrs={'class':'textinputclass'}),
'text':forms.Textarea(attrs={'class':'textareaclass editable'}),
}
def __init__(self, *args, **kwargs):
super(PostForm, self).__init__(*args, **kwargs)
self.fields['image'].required = False
I am getting the error in the Mixin, on this line python context['tags'] = Tag.objects.all()
Can anyone tell me why I am getting an error of python name 'Tag' is not defined
So far I have changed the casing of the word, I have changed the name, but none of it works.
Thank you for any help you can give :)

AttributeError with Django Rest nested serializer

I'm following the Django Rest documentation for writing nested serializer but it is giving me attribute error.
Here are my models:
class Objects(TimeStampModel):
projects = models.ForeignKey(Projects,related_name='proj_obj',on_delete=models.CASCADE)
object_name = models.CharField(max_length=50)
object_description = models.TextField()
object_main_table = models.CharField(max_length=50)
object_primary_key = models.CharField(max_length=50)
object_age_field = models.CharField(max_length=50)
date_format = models.CharField(max_length=50)
def __str__(self):
return self.object_name
class ObjectDefinition(TimeStampModel):
ATTRIBUTE = 'Attribute'
RELATION = 'Relation'
TYPE_CHOICES = (
(ATTRIBUTE, 'Attribute'),
(RELATION, 'Relation'),
)
obj = models.ForeignKey(Objects,related_name='obj_def',on_delete=models.CASCADE)
from_table = models.CharField(max_length=50)
from_table_field = models.CharField(max_length=50)
to_table = models.CharField(max_length=50)
to_table_field = models.CharField(max_length=50)
relation_type = models.CharField(max_length=50,choices=TYPE_CHOICES)
relation_sequence = models.CharField(max_length=50)
value_field = models.CharField(max_length=50, blank=True, null=True)
Here is my serializers.py snippet:
class ObjectDefinitionSerializer(serializers.ModelSerializer):
class Meta:
model = ObjectDefinition
fields = ('from_table','from_table_field','to_table','to_table_field','relation_type','value_field')
class ObjectSerializer(serializers.ModelSerializer):
definition = ObjectDefinitionSerializer(many=True)
object_description = serializers.CharField(required=False, allow_null=True, allow_blank=True
)
class Meta:
model = Objects
fields = ('projects','object_name','object_description','object_main_table','object_primary_key','object_age_field','date_format','definition')
def validate(self, data, *args, **kwargs):
date_format = data.get('date_format')
if date_format not in ['YYYYMMDD', 'DDMMYYYY']:
msg = ('Date format is incorrect')
raise serializers.ValidationError({'error_msg': msg})
return super(ObjectSerializer, self).validate(data, *args, **kwargs)
def create(self, validated_data):
definition_data = validated_data.pop('definition')
obj = Objects.objects.create(**validated_data)
for data in definition_data:
ObjectDefinition.objects.create(obj=obj, **data)
return obj
My views.py:
class CreateObject(CreateAPIView):
permission_classes = (IsAuthenticated,)
serializer_class = ObjectSerializer
After hitting POST, objects.create works fine for both the models but at return obj, it throws me this error:
Exception Value:
Got AttributeError when attempting to get a value for field definition on serializer ObjectSerializer.
The serializer field might be named incorrectly and not match any attribute or key on the Objects instance.
Original exception text was: 'Objects' object has no attribute 'definition'.
What am I missing?

The ObjectDefinition.obj's related_name is obj_def which doesn't match your serializer.
You can fix that by providing the source argument:
definition = ObjectDefinitionSerializer(source='obj_def', many=True)

Take last object in queryset and set value in field

I have app in Django 1.8 and I want to take last object (based on pub_date) and set for this object filed is_mainteaser on True and rest ssould be set on False.
Here is my code, but latest object hasn't field set to True.
class ArticleListView(ListView):
model = Article
queryset = Article.objects.order_by('-pub_date')
def get_context_data(self, **kwargs):
context = super(ArticleListView, self).get_context_data(**kwargs)
lates_object = Article.objects.latest('pub_date')
lates_object.is_mainteaser = True
return context
Here is my model:
class Article(model.Models):
title = models.CharField(max_length=255)
short_text = models.TextField(max_length=10000, default='')
image = FilerImageField(null=True)
pub_date = models.DateTimeField('date published')
online_from = models.DateTimeField('online from', blank=True)
online_to = models.DateTimeField('online to', blank=True)
position = models.PositiveIntegerField(default=0)
is_mainteaser = models.BooleanField(default=False)
def __str__(self):
return self.title
class Meta:
ordering = ['position']

When you have object instance and change model attribute you must save instance. Example:
lates_object = Article.objects.latest('pub_date')
lates_object.is_mainteaser = True
lates_object.save()
I think better for this solution is use django signals or action when you add new article. In ListView is't good solution to do it that.