I want get college data using general_info foreign key. without making nested serializer of college_set in GeneralInfo serializer. Is there any alternative in django rest framework or is not possible? I have tried above below line of code but its not working. is there any other way?
college = serializers.CharField(source='general_info.college_set', read_only=True)
models.py
from django.db import models
class GeneralInfo(models.Model):
first_name = models.CharField(max_length=30)
last_name = models.CharField(max_length=30)
address = models.CharField(max_length=30)
class Student(models.Model):
general_info = models.ForeignKey(to=GeneralInfo, on_delete=models.PROTECT)
course = models.CharField(max_length=30)
marks = models.CharField(max_length=30)
class College(models.Model):
general_info = models.OneToOneField(to=GeneralInfo, on_delete=models.PROTECT)
name = models.CharField(max_length=30)
address = models.CharField(max_length=30)
picture = models.ImageField(null=True, blank=True, upload_to='users/')
serializer.py
from rest_framework import serializers
class MySerializer(serializers.ModelSerializer):
name = serializers.CharField(source='general_info.first_name', read_only=True)
college = serializers.CharField(source='general_info.college_set', read_only=True)
class Meta:
model = Student
fields = ('name', 'college')
Related
I am creating an API to save class teachers. Now all the fields in the ClassTeacher model are foreign fields so I am using a SlugRelatedField in the serializer. It looks like SlugRelatedField does not support attribute lookup like this "user__username" and raises attribute error HOWEVER the object is still being saved.
models.py
class ClassTeacher(models.Model):
teacher = models.ForeignKey(Teacher, on_delete=models.CASCADE)
class_name = models.ForeignKey(Classes, on_delete=models.CASCADE)
school_id = models.ForeignKey(School, on_delete=models.CASCADE)
serializers.py
class ClassTeacherSerializer(ModelSerializer):
teacher = SlugRelatedField(slug_field='user__username', queryset=Teacher.objects.all()) <---- this is causing the error
class_name = SlugRelatedField(slug_field='class_name', queryset=Classes.objects.all())
school_id = SlugRelatedField(slug_field='school_id__username', queryset=School.objects.all()) <---- and I am assuming that this will too
class Meta:
model = ClassTeacher
fields = '__all__'
I tried adding a #property in the Teacher model to retrieve the username and use the property in the slug_field but that did not work too.
How can I save the object without getting the error?
EDIT 1:
teachers/models.py
class Teacher(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
name = models.CharField(max_length=30)
photo = models.URLField()
teacher/serializers.py
class TeacherSerializer(ModelSerializer):
class Meta:
model = Teacher
fields = '__all__'
school/models.py
class School(models.Model):
school_id = models.OneToOneField(User, on_delete=models.CASCADE)
principal = models.CharField(max_length=50)
name = models.CharField(max_length=50)
photo = models.URLField()
school/serializers.py
class SchoolSerializer(ModelSerializer):
class Meta:
model = School
fields = '__all__'
EDIT 2:
Here's how I used the #property by referring from here:
teacher/models.py
class Teacher(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
name = models.CharField(max_length=30)
photo = models.URLField()
#Here's the extra property part
#property
def username(self):
return self.user.username
classteacher/serializers.py
class ClassTeacherSerializer(ModelSerializer):
#Here I changed user__username to just username as mentioned in the above link
teacher = SlugRelatedField(slug_field='username', queryset=Teacher.objects.all())
class_name = SlugRelatedField(slug_field='class_name', queryset=Classes.objects.all())
school_id = SlugRelatedField(slug_field='school_id__username', queryset=School.objects.all())
class Meta:
model = ClassTeacher
fields = '__all__'
try renaming serializer field from teacher to user and using slug_field='username'
You can use #property for example
class User(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
name = models.CharField(max_length=30)
photo = models.URLField()
#property
def get_username(self):
return Teacher.objects.filter(user_id=self.id)
and than inside your ClassTeacherSerializer use slug_field='username'
let me know if it works.
I have a number of different models connected to the User model through a foregin key relationship. I would now like to display all the attributes from the objects connected to the User model in the main admin overview.
models.py
class User(AbstractBaseUser):
username = models.CharField(max_length=60)
lastname = models.CharField(max_length=60, blank=True)
class UserProfile(models.Model):
user_id = models.OneToOneField(
User,
on_delete=models.CASCADE,
primary_key=True,
)
address = models.CharField(max_length=60, blank=True)
admin.py
class UserProfileAdmin(admin.ModelAdmin):
list_display = ('user_firstname', 'user_lastname', 'address')
def user_firstname(self, instance):
return instance.user_id.username
def user_lastname(self, instance):
return instance.user_id.lastname
admin.site.register(UserProfile, UserProfileAdmin)
The code above works perfectly well to display attributes from "User" in "Userprofile", but how do I do this the other way around? In my code I currently have 4 different objects connected to the User object so keen to find a way to display all the data there.
use inlines
models.py
class Author(models.Model):
name = models.CharField(max_length=100)
class Book(models.Model):
author = models.ForeignKey(Author, on_delete=models.CASCADE)
title = models.CharField(max_length=100)
admin.py
class BookInline(admin.TabularInline):
model = Book
class AuthorAdmin(admin.ModelAdmin):
inlines = [
BookInline,
]
more info read https://docs.djangoproject.com/en/3.1/ref/contrib/admin/#inlinemodeladmin-objects
I have two models in my Django-REST application.
a ProjectRequest and a ContactRequest
I want to make it so, each Projectrequest contains a list of the refered Contactrequests.
class ProjectRequest(models.Model):
project_name = models.CharField(max_length=50)
company_name = models.CharField(max_length=50)
#make array of technologiestechnologies = models.ArrayField(base_field=) (blank=True)
project_description = models.CharField(max_length=200)
project_type = models.CharField(max_length=30)
budget_estimation = models.IntegerField(
default=1000,
validators=[
MinValueValidator(1800),
MaxValueValidator(5000000)
])
#time_estimation = models.DateTimeField(default=None, blank=True, null=True)
class ContactRequest(models.Model):
topic = models.CharField(max_length=30)
description = models.CharField(max_length=200)
time = models.CharField(max_length=15)
project_request = models.ForeignKey(ProjectRequest,
on_delete=models.CASCADE)
so far I have established a relationship, with a foreign key, which works fine as of now. However I want to extends the functionality, so, that the ProjectRequest contains a list of all the projectrequest. I have tried with several different fields, without any luck, and the documentation I can only find fields for ManyToMany and OneToOne. How can this be achieved?
There are many ways to achive what you want. For that, lets add a reverse relation in model named contact_requests:
project_request = models.ForeignKey(ProjectRequest, on_delete=models.CASCADE, related_name="contact_requests")
Now you can use PrimaryKeyRelatedField to show Primary Keys of the ContactRequest attached to each ProjectRequest.
class ProjectRequestSerializer(serializers.ModelSerializer):
contact_requests = serializers.PrimaryKeyRelatedField(many=True, read_only=True)
class Meta:
model = ProjectRequest
fields = ('contact_requests', 'company_name', ...) # other fields
Or if you want all the values of each contact_requests, then you can use nested relationship like this:
class ProjectRequestSerializer(serializers.ModelSerializer):
contact_requests = ContactRequestSerializer(many=True, read_only=True)
class Meta:
model = ProjectRequest
fields = ('contact_requests', 'company_name', ...) # and so on
You could add a property function to the ProjectRequest class that retruns all the ContactRequests that are related to that ProjectRequest like so...
class ProjectRequest(models.Model):
project_name = models.CharField(max_length=50)
company_name = models.CharField(max_length=50)
#make array of technologiestechnologies = models.ArrayField(base_field=) (blank=True)
project_description = models.CharField(max_length=200)
project_type = models.CharField(max_length=30)
budget_estimation = models.IntegerField(
default=1000,
validators=[
MinValueValidator(1800),
MaxValueValidator(5000000)
])
#time_estimation = models.DateTimeField(default=None, blank=True, null=True)
#property
def contact_requests(self):
return ContactRequest.objects.filter(project_request=self)
class ContactRequest(models.Model):
topic = models.CharField(max_length=30)
description = models.CharField(max_length=200)
time = models.CharField(max_length=15)
project_request = models.ForeignKey(ProjectRequest,
on_delete=models.CASCADE)
I had this problem too. This is how I solved it:
ContactRequest= models.ManyToManyField(ContactRequest,related_name="+")
I'm trying to add a data using "Array Model Field"(djongo) as shown Djongo Documentation(Array Model Field) or
from djongo import models
class Blog(models.Model):
name = models.CharField(max_length=100)
tagline = models.TextField()
class Meta:
abstract = True
class MetaData(models.Model):
pub_date = models.DateField()
mod_date = models.DateField()
n_pingbacks = models.IntegerField()
rating = models.IntegerField()
class Meta:
abstract = True
class Author(models.Model):
name = models.CharField(max_length=200)
email = models.EmailField()
class Meta:
abstract = True
def __str__(self):
return self.name
class Entry(models.Model):
blog = models.EmbeddedModelField(
model_container=Blog,
)
meta_data = models.EmbeddedModelField(
model_container=MetaData,
)
headline = models.CharField(max_length=255)
body_text = models.TextField()
authors = models.ArrayModelField(
model_container=Author,
)
n_comments = models.IntegerField()
def __str__(self):
return self.headline
Into admin.py I added for registration of model in admin panel
from django.contrib import admin
from .models import Entry
admin.site.register(Entry)
And when I try to add a data via http://localhost:8000/admin/ I have a MigrationError...
Where is my mistake? And what am I not understanding?
You should use models.ObjectIdField() on all models to avoid calling django migrations.
Example:
class Author(models.Model):
_id = models.ObjectIdField()
name = models.CharField(max_length=200)
email = models.EmailField()
class Meta:
abstract = True
def __str__(self):
return self.name
See more in Djongo Docs
I'm a stupid. Sry. I didn't 'makemigration' after update a model.
And so here's what I did to make it work:
1. After update a model I did 'python manage.py makemigrations' and that power on.
I have just started learning Django Rest Framework and trying to make a simple API using Django rest Framework.
This is my models.py
from __future__ import unicode_literals
from django.db import models
class Student(models.Model):
created = models.DateTimeField(auto_now_add=True)
name = models.CharField(max_length=150, blank=False)
student_id = models.CharField(max_length=20, primary_key=True)
father_name = models.CharField(max_length=150)
mother_name = models.CharField(max_length=150)
class Meta:
ordering = ('student_id',)
class Subject(models.Model):
created = models.DateTimeField(auto_now_add=True)
subject_id = models.CharField(max_length=20, primary_key=True)
name = models.CharField(max_length=150)
class Meta:
ordering = ('subject_id',)
class Result(models.Model):
created = models.DateTimeField(auto_now_add=True)
grade = models.DecimalField(max_digits=5, decimal_places=3, blank=False)
student_id = models.ForeignKey(Student, on_delete=models.CASCADE)
subject_id = models.ForeignKey(Subject, on_delete=models.CASCADE)
class Meta:
ordering = ('created',)
And this is my serializers.py
from rest_framework import serializers
from models import *
class StudentSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = Student
fields = ('student_id', 'name', 'father_name', 'mother_name')
class SubjectSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = Subject
fields = ('subject_id', 'name')
class ResultSerializer(serializers.HyperlinkedModelSerializer):
class Meta:
model = Result
fields = ('grade', 'student_id', 'subject_id')
In my "Result" model, I have two foreign keys; student_id and subject_id. This is how it looks like:
My questions is, how can I show the "name" field in the drop down menu in stead of showing "Student Object" and "Subject Object"?
I have tried with
STUDENT_CHOICES = [(each.student_id, each.name) for each in Student.objects.all()]
SUBJECT_CHOICES = [(each.subject_id, each.name) for each in Subject.objects.all()]
in the model's "choices=" field but it didn't work out.
Thanks in advance.
I think you're looking for this part of the DRF documentation.
Basically, your Django model's own representation is used. So for example, in your Student model you can add __str__ method:
# this is for Python 3, use __unicode__ on Python 2
def __str__(self):
return self.name
Meta options documentation for Django is here, look for model methods.