I have three models : Domain Topic Post
Topic has a foreign key to Domain and Post has a foreign key to Topic.
Post has a field updated_on.
I want to annotate last_updated field in Domain queryset which would contain the latest post object from Post .
Edit 1: Added models definition:
class Board(models.Model):
name = models.CharField(max_length=30, unique=True)
description = models.CharField(max_length=50)
creation_time = models.DateTimeField(auto_now_add=True)
class Topic(models.Model):
subject = models.CharField(max_length=300, unique=True)
board = models.ForeignKey(Board, on_delete=models.SET_NULL, related_name='topics', null=True)
created_by = models.ForeignKey(User, on_delete=models.SET_NULL, related_name='topics', null=True)
created_on = models.DateTimeField(auto_now_add=True)
views = models.PositiveIntegerField(default=0)
class Post(models.Model):
message = models.CharField(max_length=5000)
created_by = models.ForeignKey(User, on_delete=models.SET_NULL, related_name='posts', null=True)
created_on = models.DateTimeField(auto_now_add=True)
topic = models.ForeignKey(Topic, on_delete=models.SET_NULL, related_name='posts', null=True)
updated_on = models.DateTimeField(default=timezone.now)
Related
I am trying to obtain in a query the data of a client and the contacts he has registered I tried to do it in the following way but it did not work.
class ClientReadOnlySerializer(serializers.ModelSerializer):
clientcontacts = ClientContactSerializer(many=True, read_only=True)
class Meta:
model = Client
fields = "__all__"
Is there any way to make this relationship nested?
these are my models
clients model
# Relations
from apps.misc.models import City, TypeIdentity, TypeCLient, CIIU
from apps.clients.api.models.broker.index import Broker
from apps.authentication.models import User
class Client(models.Model):
id = models.CharField(max_length=255, unique=True,primary_key=True, editable=False)
type_client = models.ForeignKey(TypeCLient, on_delete=models.CASCADE, blank=True)
type_identity = models.ForeignKey(TypeIdentity, on_delete=models.CASCADE, blank=True)
document_number = models.CharField(max_length=255, blank=True, unique=True)
first_name = models.CharField(max_length=255, blank=True, null=True)
last_name = models.CharField(max_length=255, blank=True, null=True)
social_reason = models.CharField(max_length=255, blank=True, null=True)
city = models.ForeignKey(City, on_delete=models.CASCADE, blank=True)
address = models.CharField(max_length=255, blank=True)
email = models.CharField(max_length=255, blank=True, unique=True)
phone_number = models.CharField(max_length=255, blank=True, unique=True)
ciiu = models.ForeignKey(CIIU, on_delete=models.CASCADE, blank=True)
broker = models.ForeignKey(Broker, on_delete=models.CASCADE, blank=True)
user = models.ForeignKey(User, on_delete=models.CASCADE, blank=True)
income = models.SmallIntegerField(blank=True, default=0)
state = models.BooleanField(default=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(null=True, default=None)
client contacts model
# Relations
from apps.clients.api.models.index import Client
class ClientContact(models.Model):
id = models.CharField(max_length=255, primary_key=True, unique=True, editable=False)
client = models.ForeignKey(Client, on_delete=models.CASCADE)
first_name = models.CharField(max_length=255)
last_name = models.CharField(max_length=255)
phone_number = models.CharField(max_length=255)
state = models.BooleanField(default=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(null=True, blank=True, default=None)
after some research I came up with a solution that doesn't seem very practical, what I did was to create a method in the serializer that queries the client's contacts as follows
class ClientReadOnlySerializer(serializers.ModelSerializer):
contacts = serializers.SerializerMethodField(method_name='get_contacts')
class Meta:
model = Client
fields = "__all__"
extra_fields = ['contacts']
def get_contacts(self, obj):
contacts = ClientContact.objects.filter(client=obj)
serializer = ClientContactSerializer(contacts, many=True)
return serializer.data
using the model and the serializer of the contact model I made a query which I added in an extra field of the customer serializer, if someone knows how to make this process more optimal please reply.
I have a user model that has to go through several tasks such as completing their information, taking some tests, and interviews. So I added a progress level field that shows the user status at the moment. this is my model:
class User(AbstractUser):
id = models.AutoField(primary_key=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now=True)
isPreRegistered = models.BooleanField(default=False)
role = models.CharField(max_length=25, null=True, choices=USER_ROLE_CHOICES, default=USER_ROLE_CHOICES[0][0])
role_id = models.CharField(max_length=10, default='applicant')
username = models.CharField(unique=True, max_length=13)
first_name = models.CharField(max_length=32, null=True, default=None)
last_name = models.CharField(max_length=64, null=True, default=None)
gender = models.CharField(max_length=10, null=True)
personalInfo = models.OneToOneField(PersonalInfo, on_delete=models.CASCADE, null=True)
contactInfo = models.OneToOneField(ContactInfo, on_delete=models.Case, null=True)
eliteInfo = models.OneToOneField(EliteInfo, on_delete=models.CASCADE, null=True)
progress_level = models.CharField(max_length=25, null=True, choices=USER_PROGRESS_LEVELS, default=USER_PROGRESS_LEVELS[0][0])
and there are multiple models which are connected to the user model using a foreign key relation.
this is one of the models I added here for instance:
class PsychologicInfo(models.Model):
id = models.AutoField(primary_key=True)
user = models.ForeignKey(User, on_delete=models.CASCADE)
final_assessment = models.TextField(null=True, blank=True)
is_approved = models.CharField(max_length=64, blank=True)
is_interviewed = models.BooleanField(default=False)
I want to write a signal or a save method that does something like this:
if the is_interviewed field was True, change that progress_level to USER_ROLE_CHOICES[1][0]
I have no idea how to do this so thanks for the tips
You can override the .save() method of PsychologicInfo
class PsychologicInfo:
...
def save(self):
super().save()
if self.is_interviewed:
self.user.role = USER_ROLE_CHOICES[1][0] # or enter value here
self.user.save()
or you can use Django signals.
I have the following models in a Django app:
class Sender(PolymorphicModel):
name = models.CharField(max_length=100)
email = models.EmailField(null=False)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
class Student(Sender):
group_name = models.CharField(max_length=100, null=True)
class Teacher(Sender):
bio = models.TextField(max_length=255, null=True)
class Connection(models.Model):
student_id = models.ForeignKey('students.Student', null=False, on_delete=models.CASCADE)
teacher_id = models.ForeignKey('teachers.Teacher', null=False, on_delete=models.CASCADE)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
class Message(models.Model):
body = models.TextField(max_length=255, null=False)
sender_id = models.ForeignKey('senders.Sender', null=False, on_delete=models.CASCADE)
connection_id = models.ForeignKey('connections.Connection', null=False, on_delete=models.CASCADE)
created_at = models.DateTimeField(auto_now_add=True)
Teacher and Student model classes both inherit from Sender; I want Connection to have specific foreign keys to Teacher and Student respectively.
When I generate and run migrations, I get
django.db.utils.OperationalError: foreign key mismatch - "connections_connection" referencing "teachers_teacher".
Am I unable to use a child model that inherits from a polymorphic model as a foreign key to another model? Is there a way to get around this, or a different paradigm I should be using? Thanks!
I found a way to do this myself by removing the polymorphic Sender class and using a GenericForeignKey for Message,
but I would love to hear alternative approaches as well.
class Student(models.Model):
name = models.CharField(max_length=100)
email = models.EmailField()
group_name = models.CharField(max_length=100, null=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
class Teacher(models.Model):
name = models.CharField(max_length=100)
email = models.EmailField()
bio = models.CharField(max_length=100, null=True)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
class Connection(models.Model):
student_id = models.ForeignKey('students.Student', null=False, on_delete=models.CASCADE)
teacher_id = models.ForeignKey('teachers.Teacher', null=False, on_delete=models.CASCADE)
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
class Message(models.Model):
body = models.TextField(max_length=255, null=False)
content_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
sender_id = models.PositiveIntegerField(null=False)
content_sender = GenericForeignKey('content_type', 'sender_id')
connection_id = models.ForeignKey('connections.Connection', null=False, on_delete=models.CASCADE)
created_at = models.DateTimeField(auto_now_add=True)
models:
class FullNameMixin(models.Model):
name_id = models.BigAutoField(primary_key = True, unique=False, default=None, blank=True)
first_name = models.CharField(max_length=255, default=None, null=True)
last_name = models.CharField(max_length=255, default=None, null=True)
class Meta:
abstract = True
class Meta:
db_table = 'fullname'
class User(FullNameMixin):
id = models.BigAutoField(primary_key = True)
username = models.CharField(max_length=255, unique=True)
email = models.CharField(max_length=255, unique=True)
token = models.CharField(max_length=255, unique=True, null=True, blank=True)
password = models.CharField(max_length=255)
role = models.IntegerField(default=1)
verified = models.BooleanField(default=False)
created_at = models.DateTimeField(auto_now_add=True, null=True, blank=True)
updated_at = models.DateTimeField(auto_now=True, null=True, blank=True)
def __str__(self):
return self.username
class Meta:
db_table = 'cga_user'
class Profile(FullNameMixin):
id = models.BigAutoField(primary_key = True)
birthday = models.DateTimeField(null=True, blank=True)
country = models.CharField(max_length=255, null=True, blank=True)
state = models.CharField(max_length=255, null=True, blank=True)
postcode = models.CharField(max_length=255, null=True, blank=True)
phone = models.CharField(max_length=255, null=True, blank=True)
profession_headline = models.CharField(max_length=255, null=True, blank=True)
image = models.ImageField(upload_to=get_upload_path, null=True, blank=True)
profile_banner = models.ImageField(upload_to=get_upload_path_banner, null=True, blank=True)
cga_user = models.OneToOneField(User, null=True, blank=True, on_delete=models.CASCADE, related_name="profile")
gender = models.CharField(
max_length=255, blank=True, default="", choices=USER_GENDER_CHOICES
)
created_at = models.DateTimeField(auto_now_add=True, null=True, blank=True)
updated_at = models.DateTimeField(auto_now=True, null=True, blank=True)
class Meta:
db_table = 'profile'
When i am creating Profile from django admin panel getting below error.
e
filename = self.upload_to(instance, filename)
File "/Users/soubhagyapradhan/Desktop/upwork/africa/backend/api/model_utils/utils.py", line 7, in get_upload_path
instance.user,
File "/Users/soubhagyapradhan/Desktop/upwork/africa/backend/env/lib/python3.8/site-packages/django/db/models/fields/related_descriptors.py", line 421, in __get__
raise self.RelatedObjectDoesNotExist(
api.models.FullNameMixin.user.RelatedObjectDoesNotExist: Profile has no user.
[24/Jul/2021 13:49:51] "POST /admin/api/profile/add/ HTTP/1.1" 500 199997
please take a look how can i fix this.
Note: User model creation working but, profile not working
I checked in drf and django admin panel .
both place not working.
The problem here is that you are declaring a User model which is in fact just a model. That's not how it works.
The User is a special type of model and if you want to change it you have to extend the AbstractUser class.
Alternatively you can connect to it via one-to-one classes in the classic user-profiles approach.
But here you are creating a user model that (besides using the reserved word 'User') has none of the requirements necessary to be treated as a user who can be authenticated and that can instantiate sessions.
> Example of a simple user-profiles architecture
> Working with User objects - Django Docs (i particularly recommend this one)
I would recommend you to read-up on django user authentication.
django=2.2.3
mariadb
This error occurs after importing model from an existing database with 'inspectdb' and changed field properties.
class Post(models.Model):
post_id = models.AutoField(primary_key=True)
post_name = models.CharField(max_length=255, blank=True, null=True)
email = models.CharField(max_length=255, blank=True, null=True)
class Rank(models.Model):
rank_id = models.AutoField(primary_key=True)
rank_type = models.IntegerField(blank=True, null=True)
created_at = models.DateTimeField()
# post_id = models.IntegerField(blank=True, null=True)
post_id = models.ForeignKey(Post, on_delete=models.SET_NULL, blank=True, null=True)
Originally, it was # post_id, but I removed "managed = False", changed it to ForeignKey and then "migrate".
As far as I know that if the "post_id" in the "Post" model is "primary_key True", it replaces the "id" value with "post_id". But "Django" keeps calling up the "post_id_id".
There is no command to refer to post_id_id elsewhere.
If you have a solution or something that I'm missing, please give me some advice.
-------Add more after commented by Daniel Roseman --------
class Post(models.Model):
post_id = models.AutoField(primary_key=True)
post_name = models.CharField(max_length=255, blank=True, null=True)
email = models.CharField(max_length=255, blank=True, null=True)
class Gallery(models.Model):
uid = models.AutoField(prymary_key=True)
gallery_name = models.CharField(...)
class Rank(models.Model):
rank_id = models.AutoField(primary_key=True)
rank_type = models.IntegerField(blank=True, null=True)
created_at = models.DateTimeField()
# post_id = models.IntegerField(blank=True, null=True)
post_id = models.ForeignKey(Post, on_delete=models.SET_NULL, blank=True, null=True)
# uid = models.IntegerField(blank=True, null=True)
uid = models.ForeignKey(Gallery, on_delete=models.SET_NULL, blank=True, null=True)
Don't call your ForeignKey post_id. Call it post. The underlying database field is post_id; Django adds the _id suffix automatically.