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ValueError: Field 'id' expected a number but got string in Django Rest Framework

In DRF I am facing an issue, whenever I do a POST request on the endpoint, on the field "name" which is a text field I get an exception "Field 'id' expected a number but got 'TITLE'", but when I change the value of "name" to an integer the request is successful I don't understand it becauses name is TextField in model and why its mixing Id and Name field with each other. I have deleted the migration files from the Project and DB and re-run the Migrations, but still facing this issue.
Following is my code:
models.py
class Project(models.Model):
admin = models.ForeignKey(User, on_delete=models.CASCADE, related_name='project_crated_by')
name = models.TextField(max_length=225, blank=False, null=False)
project_members = models.ForeignKey(User, on_delete=models.CASCADE, verbose_name='members', null=True, blank=True)
created_on = models.DateField(default=timezone.now)
tags = ArrayField(models.CharField(max_length=225, default=''), blank=True)
def __str__(self):
return self.name
objects = models.Manager()
views.py
class ProjectView(viewsets.ViewSet):
def create(self, request):
project_name_exist = Project.verify_project_name(request.data['admin'], request.data['name'])
if project_name_exist:
return Response({'message': 'You already have a project with this name',
'status': status.HTTP_200_OK})
serialized_project = ProjectSerializer(data=request.data)
if serialized_project.is_valid():
serialized_project.save()
return Response({'message': 'Project Created Successfully', 'status': status.HTTP_201_CREATED})
else:
return Response({'error': serialized_project.errors, 'status': status.HTTP_400_BAD_REQUEST})
serializer.py
class ProjectSerializer(serializers.ModelSerializer):
class Meta:
model = Project
fields = '__all__'

A more generic and non-DIY solution is to use UniqueTogetherValidator on your serializer and let Django sort it out.
from rest_framework.validators import UniqueTogetherValidator
class ProjectSerializer(serializers.ModelSerializer):
class Meta:
model = Project
fields = '__all__'
validators = [
UniqueTogetherValidator(
queryset=Project.objects.all(),
fields=['admin', 'name'],
message='You already have a project with this name'
)
]
And/or add it to the model for enforcing it on the database.
class Project(models.Model):
admin = models.ForeignKey(User, on_delete=models.CASCADE, related_name='project_crated_by')
name = models.TextField(max_length=225, blank=False, null=False)
project_members = models.ForeignKey(User, on_delete=models.CASCADE, verbose_name='members', null=True, blank=True)
created_on = models.DateField(default=timezone.now)
tags = ArrayField(models.CharField(max_length=225, default=''), blank=True)
def __str__(self):
return self.name
objects = models.Manager()
class Meta:
unique_together = ("admin", "name")

Add Extra fields in serializer from one to one relation models

In this project, I have two models Student and Parent related to each other through one to one field.
In Parent serializer, I want to add Students attributes like age. I am thinking of using SerializerMethodField for both cases is their any better way to do it?
I am not getting the queries on how to get the object attributes and little explanation would be great.
Here what I have done till now.
Models.py
class Student(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True, default=None)
batch = models.ForeignKey(Batch, on_delete=models.CASCADE, null=True, related_name='students')
email = models.EmailField(null=True)
phone_number = models.CharField(max_length=10, null=True)
dob = models.DateField(blank=True, null=True, help_text="Enter in the following format : YYYY-MM-DD")
address = models.TextField(max_length=150, null=True)
age = models.IntegerField(blank=True)
image = models.ImageField(upload_to='profile_pictures', default='student_image.png', blank=True)
#property
def remarks(self):
return self.remark_set.all()
#property
def marks(self):
return self.marks_set.all()
def __str__(self):
return self.user.firstName + ' ' + self.user.lastName
class Parent(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True, default=None)
child = models.ForeignKey(Student, on_delete=models.CASCADE)
email = models.EmailField(null=True)
phone_number = models.CharField(max_length=10, null=True)
address = models.TextField(max_length=150, null=True)
image = models.ImageField(upload_to='profile_pictures', default='student_image.png', blank=True)
def __str__(self):
return self.user.firstName + ' ' + self.user.lastName
Serilaizer.py
class ParentSerializer(serializers.HyperlinkedModelSerializer):
student_age = serializers.SerializerMethodField()
student_batch = serializers.SerializerMethodField()
parent_name = serializers.SerializerMethodField()
class Meta:
model = Parent
fields = "__all__"
def get_student_age(self, obj):
return Parent.objects.get(child__age = self.obj.user.child)
def get_student_batch(self, obj):
return Parent.objects.get(child__bacth = self.obj.user.child)
def get_parent_name(self, user):
return Parent.objects.get(user=self.request.user)
Views.py
class ParentView( mixins.ListModelMixin, mixins.RetrieveModelMixin,viewsets.GenericViewSet):
queryset = Parent.objects.all()
serializer_class = serializers.ParentSerializer

first way:
from apps.models import Student, parent
class BasicUserSerializer(serializers.ModelSerializer):
class Meta:
model = User
fields = "__all__"
class BasicStudentSerializer(serializers.ModelSerializer):
class Meta:
model = Student
fields = "__all__"
class ParentSerializer(serializers.ModelSerializer):
user = BasicUserSerializer(read_only=True,many=False)
child = BasicStudentSerializer(read_only=True, many=True)
class Meta:
model = Parent
fields = '__all__'
you can do this way . its replace a serializer field that you want and if parent have several child then in child's field you have new all child's information as dictionary.
================================================================
second way is use HyperLinkModel .
class ParentSerializer(serializers.ModelSerializer):
user = serializers.HyperlinkedRelatedField(read_only=True,many=False)
child = serializers.HyperlinkedRelatedField(read_only=True, many=True)
class Meta:
model = Parent
fields = '__all__'
but notice that in first way you will have a independent serializer class that every time you need to serialize model class that related to User or Child you can use them simply.

Django Rest Framework requieres as not null look up field

I have two models:
class Album(models.Model):
code = models.CharField(max_length=10, primary_key=True, default=_create_access_code, verbose_name=_("Id"))
name = models.CharField(max_length=200, verbose_name=_("Name"))
description = models.TextField(null=True, blank=True, verbose_name=_("Description"))
company = models.ForeignKey(Company, on_delete=models.PROTECT, related_name='albums', verbose_name=_("Company"))
access_code = models.CharField(max_length=10, default=_create_access_code, verbose_name=_("Internal Use"))
class Meta:
verbose_name = _("Album")
verbose_name_plural = _("Albums")
def __str__(self):
return "[{}] {} ({})".format(self.pk, self.name, self.company.id)
class Photo(models.Model):
name = models.CharField(max_length=100, null=True, blank=True, verbose_name=_("Name"))
album = models.ForeignKey(Album, on_delete=models.CASCADE, related_name='photos', verbose_name=_("Album"))
photo = models.ImageField(verbose_name=_("Photo"))
class Meta:
verbose_name = _("Photo")
verbose_name_plural =_("Photos")
def __str__(self):
return "[{}] {}".format(self.pk, self.name)
I am trying to make a post to the ModelViewSet for model Albums, but I get an error indicating that field photos is required. Even the OPTIONS method indicates it es required.
How can I instruct DRF for not considering look up fields as required? Is it some serializer setting?

You can add required=False to fields in the serializer.
photos = PhotoSerializer(many=True, required=False)
Something like this. Can you post you serializers?

Many to Many model with a dropdown in Django Rest Framework?

I am trying to create a Many to Many relation with a model in between, I have a Client model, and a Zone model, each client may have access to different zones, and each zone may have multiple clients.
Therefore I created a model called Access Permission, that stores said relation, and I want to show a dropdown selector in the post form that shows the existing clients and zones, or to ask for the Id of an existing object, instead of showing the form to create new ones.
These are my models:
class Zone(models.Model):
name = models.TextField()
created = models.DateTimeField(auto_now=True)
def __str__(self):
return '%s' % (self.name)
class Client(models.Model):
name = models.TextField()
birthDate = models.DateField()
created = models.DateTimeField(auto_now=True)
def __str__(self):
return '%s' % (self.name)
class AccessPermission(models.Model):
idClient = models.ForeignKey(Client, on_delete=models.CASCADE, null=False)
idZone = models.ForeignKey(Zone, on_delete=models.CASCADE, null=False)
And these my current serializers:
class ZoneSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = Zone
fields = ('name',)
class ClientSerializer(serializers.HyperlinkedModelSerializer):
zones = ZonesSerializer(source='accesspermission_set', many=True, read_only=True)
class Meta:
model = Client
fields = ('name', 'birthDate', 'zones')
class AccessPermissionSerializer(serializers.ManyRelatedField):
idClient = ClientSerializer(many=False)
idZone = ZoneSerializer(many=False)
class Meta:
model = AccessPermission
fields = ('idClient', 'idZone')
Is there any way to ask for the Id of an existing object, or show the existing ones, instead of the fields to create new ones?

You can do it like:
models
class AccessPermission(models.Model):
client = models.ForeignKey(Client, on_delete=models.CASCADE, null=False)
zone = models.ForeignKey(Zone, on_delete=models.CASCADE, null=False)
serializers
class AccessPermissionSerializer(serializers.ManyRelatedField):
id = serializers.IntegerField(read_only=True)
client_id = serializers.PrimaryKeyRelatedField(
queryset=Client.objects.all(), source='client', allow_null=False, required=True
)
zone_id = serializers.PrimaryKeyRelatedField(
queryset=Zone.objects.all(), source='zone', allow_null=False, required=True
)
class Meta:
model = AccessPermission
fields = (
'id', 'client_id', 'zone_id'
)

Dynamic models django

Let's say i have 10 tables in 1 Db and the table names differ and data is different, but the structure of the tables are the same. And then i have 1 more table that collects all the table names and the creation date of that table.
Example:
PrimaryTable
table_name_1
table_name_2
....
table_name_10
and the structure of all tables example:
class PrimaryTable(models.Model):
name = models.CharField(db_column='Name', unique=True, max_length=100)
date = models.CharField(db_column='Date', max_length=100)
class Meta:
managed = True
db_table = 'Primary Table'
def __str__(self):
return self.name
class table_name_1(models.Model):
title = models.TextField(db_column='Title', blank=True, null=True)
url = models.CharField(db_column='Url', unique=True, max_length=250, blank=True,
null=True)
description = models.TextField(db_column='Description', blank=True, null=True)
created_at = models.DateTimeField(db_column='Created_at')
class table_name_2(models.Model):
title = models.TextField(db_column='Title', blank=True, null=True)
url = models.CharField(db_column='Url', unique=True, max_length=250, blank=True,
null=True)
description = models.TextField(db_column='Description', blank=True, null=True)
created_at = models.DateTimeField(db_column='Created_at')
and so on...
And i only want to make 1 class that includes all those tables that have same structure and call it when i choose the table from the PrimaryTable.
I don't want to use "python manage.py inspectdb > models.py" every time i create a table. I want to have access to the new created table instantly when i create it.

You can define your model fields as dict:
fields = dict(
title = models.TextField(db_column='Title', blank=True, null=True),
url = models.CharField(db_column='Url', unique=True, max_length=250, blank=True, null=True),
description = models.TextField(db_column='Description', blank=True, null=True),
created_at = models.DateTimeField(db_column='Created_at'),
)
Then you can dynamicly create and run migration for it:
from django.db import connection, migrations, models
from django.db.migrations.executor import MigrationExecutor
def create_table(table_name, model_fields, app_label):
class Migration(migrations.Migration):
initial = True
dependencies = []
operations = [
migrations.CreateModel(
name=table_name,
fields=[
('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
] + [(k, field) for k,field in model_fields.items()],
options={
'db_table': table_name,
},
),
]
executor = MigrationExecutor(connection)
migration = Migration(table_name, app_label)
with connection.schema_editor(atomic=True) as schema_editor:
migration.apply(executor._create_project_state(), schema_editor)
Then you can use dynamic model creation to access data in tables:
from django.db import models
def create_model(name, fields=None, app_label=None, module='', options=None, admin_opts=None):
"""
Create specified model
"""
class Meta:
db_table = name
if app_label:
# app_label must be set using the Meta inner class
setattr(Meta, 'app_label', app_label)
# Update Meta with any options that were provided
if options is not None:
for key, value in options.iteritems():
setattr(Meta, key, value)
# Set up a dictionary to simulate declarations within a class
attrs = {'__module__': module, 'Meta': Meta}
# Add in any fields that were provided
if fields:
attrs.update(fields)
# Create the class, which automatically triggers ModelBase processing
model = type(name, (models.Model,), attrs)
return model
I hope you will get general idea.
I took code from project that uses Django 2 (similar code is used to create tables per uploaded CSV file, columns and name of each uploaded CSV is stored in table which is similar to your PrimaryTable).

You can simplify things by keeping all of the data with the same structure in one table. You can use admin filters and custom manager methods to focus on one type of information at a time, which will provide the same functionality as separate tables.
class Information(models.Model):
name = models.CharField(db_column='Name', unique=True, max_length=100)
date = models.CharField(db_column='Date', max_length=100)
information_type = models.ForeignKey(InformationType, related_name='information_records')
def __str__(self):
return self.name
class InformationType(models.Model):
title = models.TextField(db_column='Title', blank=True, null=True)
url = models.CharField(db_column='Url', unique=True, max_length=250, blank=True,
null=True)
description = models.TextField(db_column='Description', blank=True, null=True)
created_at = models.DateTimeField(db_column='Created_at')
def __str__(self):
return self.title

k i figure out but i dont know how to write it.
I m going to create 1 class in models:
Example models.py:
class Alltables(models.Model):
title = models.TextField(db_column='Title', blank=True, null=True) # Field name made lowercase.
url = models.CharField(db_column='Url', unique=True, max_length=250, blank=True,
null=True) # Field name made lowercase.
description = models.TextField(db_column='Description', blank=True, null=True) # Field name made lowercase.
created_at = models.DateTimeField(db_column='Created_at') # Field name made lowercase.
class Meta:
managed = False
db_table = 'Table_name' # make it args
def __str__(self):
return self.url
and in the class Meta i want to implement Args at db_table.
That means when i click on a table in the html i want that table name to be inserted in the db_table and give me the data in it.
Because the class PrimaryTable will give me all the table names in that DB.
I hope i ve explained k. But i still need the answer of how to implement args in the Meta class. and Use it in the views.py and html template.
tables/views.py
def table_base(request):
table_name = Crawledtables._meta.db_table
list_tables = Crawledtables.objects.order_by('id')
table_list = {'list_tables': list_tables}
return render(request, 'tables/table_base.html', {'table_name': table_name,
'list_tables': list_tables})
class AboutDetail(DetailView):
model = Crawledtables
pk_url_kwarg = 'table_id'
template_name = 'tables/table_list.html'
def get_object(self):
if 'table_id' not in self.kwargs:
return Crawledtables.objects.get(id=1)
else:
return Crawledtables.objects.get(id=self.kwargs['table_id'])
part of tables/views.py
class Details(ListView):
model = table_name_1
template_name = 'tables/table_list.html'
context_object_name = 'details'
paginate_by = 15
queryset = table_name_1.objects.all()