django import-export how to add foreign key - python

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.

Related

Django import-export with FK constraint

I have been attempting to import data into my Django project using Django import-export. I have two models Ap and Job, Job has a FK relationship with Ap. Using the Admin, I can select the file and the type, CSV. So far my program seems to run, but gets hung up on the FK. I'm close, something is off and causing the import script to fail.
Models.py
class Ap(models.Model):
line_num = models.IntegerField()
vh = models.IntegerField()
vz = models.IntegerField()
status = models.CharField(
choices=statuses, default="select", max_length=40)
classified = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
class Job(models.Model):
aplink = models.ForeignKey(Ap, related_name=(
"job2ap"), on_delete=models.CASCADE)
job_num = models.IntegerField()
description = models.CharField(max_length=200)
category = models.CharField(
choices=categories, default="select", max_length=40)
status = models.CharField(
choices=statuses, default="select", max_length=40)
dcma = models.BooleanField(default=False),
due_date = models.DateField(blank=True),
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
views.py
class ImportView(View):
def get(self, request):
form = ImportForm()
return render(request, 'importdata.html', {'form': form})
def post(self, request):
form = ImportForm(request.POST, request.FILES)
job_resource = JobResource()
data_set = Dataset()
if form.is_valid():
file = request.FILES['import_file']
imported_data = data_set.load(file.read())
result = job_resource.import_data(
data_set, dry_run=True) # Test the data import
if not result.has_errors():
job_resource.import_data(
data_set, dry_run=False) # Actually import now
else:
form = ImportForm()
return render(request, 'importdata.html', {'form': form})
resource.py
class CharRequiredWidget(widgets.CharWidget):
def clean(self, value, row=None, *args, **kwargs):
val = super().clean(value)
if val:
return val
else:
raise ValueError('this field is required')
class ForeignkeyRequiredWidget(widgets.ForeignKeyWidget):
def clean(self, value, row=None, *args, **kwargs):
if value:
print(self.field, value)
return self.get_queryset(value, row, *args, **kwargs).get(**{self.field: value})
else:
raise ValueError(self.field + " required")
class JobResource(resources.ModelResource):
aplink = fields.Field(column_name='aplink', attribute='aplink', widget=ForeignkeyRequiredWidget(Ap,'id'),
saves_null_values=False)
job_num = fields.Field(saves_null_values=False, column_name='job_num', attribute='job_num',
widget=widgets.IntegerWidget())
description = fields.Field(column_name='description', attribute='description', saves_null_values=False,
widget=CharRequiredWidget())
class Meta:
model = Job
fields = ('aplink', 'job_num', 'description',)
clean_model_instances=True
admin.py
class JobResource(resources.ModelResource):
class Meta:
model=Job
fields=('aplink','job_num','description',)
class JobAdmin(ImportExportModelAdmin):
resource_class = JobResource
admin.site.register(Job, JobAdmin)
CSV file, data to import. I have tried leaving the first column empty, as will as putting the Id of the only Ap stored in the table ie 1. I have also tried hard coding the line_num, which is 1200 the first column as well.
CSV file for importing data:
Date importing errors:
In your resources, while defining fields, you need to include id field in the list. So change JobResource to the following:
class JobResource(resources.ModelResource):
class Meta:
model = Job
fields = ('id', 'aplink', 'job_num', 'description')
If you have defined a custom id field, then you will need to provide:
import_id_fields = ('your_id_field')

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)

Writing a view to allow user to add related data for a customer, like comments for example; on a single page

I have working models, forms, views and urls for a django CRUD app managing customer functions for a business. I just cant seem to figure out how to write a view to allow a user to add comments, or other data related to the customer and stored in other models using a single view and template.
So for example; for customer a, all the comments for customer a with the option to add, amend etc.. and the same for the other related models.
I understand how to do it for one I will be able to make quick progress. (old school programmer here)
Here is what I am working with - keeping it simple.
MODELS
class Emergency(models.Model):
# Fields
name = CharField(null = False, blank = False, max_length=60)
address = TextField(blank=True, null=True, help_text='Street and town', verbose_name='Address')
telephone = CharField(blank=False, null=False, unique= True, max_length=20)
relationship = CharField(choices=(('P', 'Parent'),('S', 'Son'),('D', 'Daughter'),('R', 'Relative'),('L', 'Partner')),max_length = 1,default='R')
class Meta:
ordering = ('-pk',)
def __unicode__(self):
return u'%s' % self.pk
def get_absolute_url(self):
return reverse('conform_emergency_detail', args=(self.pk,))
def get_update_url(self):
return reverse('conform_emergency_update', args=(self.pk,))
class Client(models.Model):
# Fields
surname = CharField(null = False, blank = False, max_length=30)
name = CharField(null = False, blank = False, max_length=60)
# Relationship Fields
emergencycontact = models.ForeignKey(Emergency, on_delete=models.CASCADE, name = 'Emergency Contact')
class Meta:
ordering = ('-pk',)
def __unicode__(self):
return u'%s' % self.pk
def get_absolute_url(self):
return reverse('conform_client_detail', args=(self.pk,))
def get_update_url(self):
return reverse('conform_client_update', args=(self.pk,))
class Clientnotes(models.Model):
# Fields
slug = AutoSlugField(populate_from='name', blank=True)
created = DateTimeField(auto_now_add=True, editable=False)
last_updated = DateTimeField(auto_now=True, editable=False)
note = CharField(blank=False, null=False, max_length= 300 )
# Relationship Fields
modified_by = models.ForeignKey(User, related_name='clientnotes_modified_by', on_delete=models.CASCADE, name= 'Changed by')
clientnotes = models.ManyToManyField(Client, name = 'Clients notes')
class Meta:
ordering = ('-created',)
def __unicode__(self):
return u'%s' % self.slug
def get_absolute_url(self):
return reverse('conform_clientnotes_detail', args=(self.slug,))
def get_update_url(self):
return reverse('conform_clientnotes_update', args=(self.slug,))
FORMS
class ClientForm(forms.ModelForm):
class Meta:
model = Client
fields = ['surname', 'name']
class ClientnotesForm(forms.ModelForm):
class Meta:
model = Clientnotes
readonly_fields = ['slug', 'modified_by']
fields = ['note']
VIEWS
class ClientListView(ListView):
model = Client
class ClientCreateView(CreateView):
model = Client
form_class = ClientForm
class ClientDetailView(DetailView):
model = Client
class ClientUpdateView(UpdateView):
model = Client
form_class = ClientForm
TEMPLATE NAMES
client_detail.html
client_form.html
client_list.html
I have simple views, forms and templates to list, view detail and add and it all works well - with the exception of related models because i am not able to add both models at the same time. I need a simple clear simpletons guide with what i have provided so it clicks into place.

Edit another model after creating an instance

I am finding it difficult to achieve the following scenario:
In my app, a user creates a project, now to that project he can link a previous team that he created or create a new team.
A team can be part of many projects but a project is linked to only ONE team.
models.py:
class Team(models.Model):
team_name = models.CharField(max_length=100, default = '')
team_hr_admin = models.ForeignKey(MyUser, blank=True, null=True)
def __str__(self):
return self.team_name
class TeamMember(models.Model):
user = models.ForeignKey(MyUser)
team = models.ForeignKey(Team)
def __str__(self):
return self.user.first_name
class Project(models.Model):
name = models.CharField(max_length=250)
team_id = models.ForeignKey(Team, blank=True, null=True)
project_hr_admin = models.ForeignKey(MyUser, blank=True, null=True)
def get_absolute_url(self):
return reverse('website:ProjectDetails', kwargs = {'pk' : self.pk})
def __str__(self):
return self.name
views.py:
class ProjectCreate(CreateView):
model = Project
fields = ['name']
template_name = 'project_form.html'
def form_valid(self, form):
form.instance.project_hr_admin = self.request.user
return super(ProjectCreate, self).form_valid(form)
class ProjectDetailView(generic.DetailView):
model = Project
template_name = 'project_details.html'
class TeamCreate(CreateView):
model = Team
fields = ['team_name']
template_name = 'team_form.html'
def form_valid(self, form):
obj = form.save(commit=False)
obj2 = Project.team_id
obj2 = obj.team_id
obj2.save()
print("sucess")
I would like that when a user creates a team, and if the team is created it successfully. Add automatically to the Project models with the corresponding team_id.
Any help would be appreciated. Thanks in advance!
Well, you can get the project with your user id which has a team_id null.
In the form_valid method of your TeamCreate() view:
def form_valid(self, form):
valid = super(TeamCreate, self).form_valid(form)
obj = form.save()
obj2 = Project.objects.get(project_hr_admin=self.request.user, team_id=None)
obj2.team_id = obj
obj2.save()
return valid
Here you just get the Project which has your user as admin and a null team_id.
Warning though, if an admin create two projects with no team, the request Project.objects.get(...) will raise an error as it will return more than one object.
So you must be sure it will always be one project and then one team created.
Hope it helps.

Django: Slugify Post Data

I'm trying to save some form data inputted by the user. I would like to slugify the "name" which was entered by the user, but dont want the slug field to show on the template that the user sees. I tried to do it manually with the sell function that you see below, but cant quite get it to work. I want to eventually save the slugified name into the Item model I have listed below. I'm sure there's a much smarter/simpler way than the sell function I'm currently using :P. Thanks in advance!
class Item(models.Model):
user = models.ForeignKey(User)
name = models.CharField(max_length=75)
slug = models.SlugField(max_length=50, unique=True)
is_active = models.BooleanField(default=True)
image = models.CharField(max_length=50)
price = models.DecimalField(max_digits=9, decimal_places=2)
quantity = models.IntegerField(default=1)
description = models.TextField()
created = models.DateTimeField(auto_now_add=True)
shipping_price = models.DecimalField(decimal_places=2, max_digits=6)
categories = models.ManyToManyField(Category)
class AddItem(forms.ModelForm):
class Meta:
model = Item
exclude = ('user','slug','is_active',)
def sell(request):
if request.method == "POST":
form = AddItem(request.POST)
item = form.save(commit=False)
item.user = request.user
item.is_active = True
item.slug = slugify(form.name) **#not sure what this line should be?**
item.save()
if form.is_valid():
form.save()
return HttpResponseRedirect('thanks.html')
else:
url = urlresolvers.reverse('register')
return HttpResponseRedirect(url)
You can exclude slug from user form.
And slugify in pre_save signal.
from django.dispatch import receiver
from django.db.models.signals import pre_save
#receiver(pre_save, sender=Item)
def iter_pre_save_handler(sender, instance, **kwargs):
if not instance.pk:
instance.slug = slugify(instance.name)
According to the docs, you can exclude a field from being rendered in a model form like this:
class PartialAuthorForm(ModelForm):
class Meta:
model = Author
fields = ('name', 'title')
or
class PartialAuthorForm(ModelForm):
class Meta:
model = Author
exclude = ('birth_date',)
or by setting editable=False on the Field instance in your model.
Once you have done this, you can override the save method of the model, as the comments in the OP have suggested:
# shamelessly copied from http://stackoverflow.com/questions/837828/how-do-i-create-a-slug-in-django/837835#837835
from django.template.defaultfilters import slugify
class test(models.Model):
q = models.CharField(max_length=30)
s = models.SlugField()
def save(self, *args, **kwargs):
self.s = slugify(self.q)
super(test, self).save(*args, **kwargs)

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