I have a SchoolClass with Members. I now want to make a Project that connects to some of the members. How do I do that?
class SchoolKlass(models.Model):
name = models.CharField(max_length=50)
members = models.ManyToManyField(UserProfile, blank=True,related_name='a')
class Meta:
verbose_name_plural = 'Klasser'
def __str__(self):
return self.user.username
class Project(models.Model):
members = models.ManyToManyField(SchoolKlass.members, blank=True)
name = models.CharField(max_length=200)
description = models.CharField(max_length=1000)
schoolKlass = models.ForeignKey(SchoolKlass, on_delete=models.CASCADE)
As you can see, I want to access SchoolKlass.members inside the manytomany relationship of the Project model.
user circular import ..
class SchoolKlass(models.Model):
name = models.CharField(max_length=50)
members = models.ManyToManyField(UserProfile, blank=True,related_name='a')
class Meta:
verbose_name_plural = 'Klasser'
def __str__(self):
return self.user.username
class Project(models.Model):
members = models.ManyToManyField("SchoolKlass.members", blank=True)
name = models.CharField(max_length=200)
description = models.CharField(max_length=1000)
schoolKlass = models.ForeignKey(SchoolKlass, on_delete=models.CASCADE)
provide the "appname.model" on relation filed. don't forget the quote,
Related
I am trying to create an educational website using django, so I have two models class and course which have a one-to-many foreignkey relationship between them i.e. one course can have several class but one class can only have one course. But this creates a problem for me. That is, in my course_detail_view I have assigned the model course. So I cannot render classes in my html file. Can anyone help me solve this ?
My models.py:
class Course(models.Model):
title = models.CharField(max_length=100)
image = models.ImageField(upload_to='class/instructor_pics', null=True)
instructor = models.CharField(max_length=100)
instructor_image = models.ImageField(upload_to='class/instructor_pics', null=True)
students = models.ManyToManyField(User, related_name='courses_joined', blank=True)
slug = models.SlugField(max_length=200, unique=True)
description = models.TextField(max_length=300, null=True)
created = models.DateTimeField(auto_now_add=True)
class Meta:
ordering = ['-created']
def __str__(self):
return self.title
class Class(models.Model):
title = models.CharField(max_length=100)
video = models.FileField(upload_to='class/class_videos',null=True,
validators=[FileExtensionValidator(allowed_extensions=['MOV','avi','mp4','webm','mkv'])])
course = models.ForeignKey(Course, on_delete=models.CASCADE, null=True, related_name='classes')
def __str__(self):
return self.title
My views.py:
class CourseDetailView(LoginRequiredMixin, DetailView):
model = Course
template_name = 'class/course.html'
Thanks in advance!
I am trying to create an educational website using django so I have a class model and a course model. I have tried to use the Many-to-one foreignkey relationship but that doesn't work, I can create classes using foreignkey but that class is not being assigned to that course only. It appears in other courses as well. So how can I make this work? What should I change?
My models.py:
class Class(models.Model):
title = models.CharField(max_length=100)
video = models.FileField(upload_to='class/class_videos',null=True,
validators=[FileExtensionValidator(allowed_extensions=['MOV','avi','mp4','webm','mkv'])])
def __str__(self):
return self.title
class Course(models.Model):
title = models.CharField(max_length=100)
image = models.ImageField(upload_to='class/instructor_pics', null=True)
instructor = models.CharField(max_length=100)
instructor_image = models.ImageField(upload_to='class/instructor_pics', null=True)
students = models.ManyToManyField(User, related_name='courses_joined', blank=True)
classes = models.ForeignKey(Class, on_delete=models.CASCADE, null=True)
slug = models.SlugField(max_length=200, unique=True)
description = models.TextField(max_length=300, null=True)
created = models.DateTimeField(auto_now_add=True)
class Meta:
ordering = ['-created']
def __str__(self):
return self.title
You are using the foreign key in the wrong model. If each class can only have one course, but a single course, can have multiple classes, you should place the ForeignKey in the class model instead of the course model. Your code would be like this:
class Course(models.Model):
title = models.CharField(max_length=100)
image = models.ImageField(upload_to='class/instructor_pics', null=True)
instructor = models.CharField(max_length=100)
instructor_image = models.ImageField(upload_to='class/instructor_pics', null=True)
students = models.ManyToManyField(User, related_name='courses_joined', blank=True)
slug = models.SlugField(max_length=200, unique=True)
description = models.TextField(max_length=300, null=True)
created = models.DateTimeField(auto_now_add=True)
class Meta:
ordering = ['-created']
def __str__(self):
return self.title
class Class(models.Model):
title = models.CharField(max_length=100)
video = models.FileField(upload_to='class/class_videos',null=True,
validators=[FileExtensionValidator(allowed_extensions=['MOV','avi','mp4','webm','mkv'])])
course = models.ForeignKey(Course, on_delete=models.CASCADE, null=True, related_name='classes')
def __str__(self):
return self.title
And when you want to list the classes of a single course, you can use this code (you should use the related_name field in the source model like the way I have used in the class model):
course = Course.objects.filter(some_filter=some_value).first()
course.classes.first() # This will return the first class of the course
I'm trying to show my all children category from parent category. I want to just hit one API end and show all tables which is related to that item. I want to hit "Master-Category" and show all releated "Category","Sub-Category" and "Root-Item" in Hierarchy form. I display all the data but cannot in Hierarchy form. Can anyone please give me the solution for this problem.
Model.py
from django.db import models
from django.contrib.auth.models import User
class MasterCategory(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE, null=True, blank=True,
verbose_name="Created By")
title = models.CharField(max_length=100, null=False, blank=False)
description = models.TextField(default='')
def __str__(self):
return str(self.title)
#property
def category(self):
data = NewCategory.objects.filter(master_category__id=self.id).values
return data
#property
def sub_category(self):
data = NewSubcategory.objects.filter(category__id=self.id).values
return data
#property
def root_item(self):
data = Rootitem.objects.filter(sub_category__id=self.id).values
return data
class NewCategory(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE, null=True, blank=True,
verbose_name="Created By")
title = models.CharField(max_length=100, null=False, blank=False)
description = models.TextField(default="")
master_category = models.ForeignKey(
MasterCategory, on_delete=models.CASCADE, null=True, blank=True)
def __str__(self):
return str(self.title)
class NewSubcategory(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE, null=True, blank=True,
verbose_name="Created By")
title = models.CharField(max_length=100, null=False, blank=False)
description = models.TextField(default="")
category = models.ForeignKey(NewCategory, on_delete=models.CASCADE, null=True,
blank=True)
def __str__(self):
return str(self.title)
class Rootitem(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE, null=True, blank=True,
verbose_name="Created By")
title = models.CharField(max_length=100, null=False, blank=False)
description = models.TextField(default="")
sub_category = models.ForeignKey(NewSubcategory, on_delete=models.CASCADE,
null=True, blank=True)
def __str__(self):
return str(self.title)
Serializers.py
I add #property function name in MasterCategorySerializer fields, "category", "sub_category", "root_item"
from .models import MasterCategory, NewCategory, NewSubcategory, Rootitem
from rest_framework import serializers
class MasterCategorySerializer(serializers.ModelSerializer):
class Meta:
model = MasterCategory
fields = ["title", 'category', 'sub_category', 'root_item']
class NewCategorySerializer(serializers.ModelSerializer):
class Meta:
model = NewCategory
fields = "__all__"
class NewSubcategorySerializer(serializers.ModelSerializer):
new_cat = NewCategorySerializer(source='category',read_only=True, many=True)
class Meta:
model = NewSubcategory
fields = "__all__"
class RootitemSerializer(serializers.ModelSerializer):
class Meta:
model = Rootitem
fields = "__all__"
**Viewset.py**
from API_app.models import MasterCategory
from API_app.serializers import MasterCategorySerializer
from rest_framework import viewsets
class MasterCategoryViewSet(viewsets.ModelViewSet):
queryset = MasterCategory.objects.all()
serializer_class = MasterCategorySerializer
My Desired Output, what i want.
{
Electronics <---- Master-Category
{
Smart-Phone <---- Category
{
Samsung <---- Sub-Category
{
Samsung S20 Ultra <---- Root-Item
}
}
}
}
Change your serializers as below. For this nested structure you don't need properties. As tables are connected with foreign key you can define related name between models and assign to its serializer. Default related name between table is tablename_set.
class RootitemSerializer(serializers.ModelSerializer):
class Meta:
model = Rootitem
fields = "__all__"
class NewSubcategorySerializer(serializers.ModelSerializer):
rootitem_set = RootitemSerializer(many=True)
class Meta:
model = NewSubcategory
fields = "__all__"
class NewCategorySerializer(serializers.ModelSerializer):
newsubcategory_set = NewSubcategorySerializer(many=True)
class Meta:
model = NewCategory
fields = "__all__"
class MasterCategorySerializer(serializers.ModelSerializer):
newcategory_set = NewCategorySerializer(many=True)
class Meta:
model = MasterCategory
fields = "__all__"
We have relationship between MasterCategory and NewCategory. As you don't define related_name therefore related name is newcategory_set and its response is NewCategorySeralizer. Make many=True because they are related with foreign key as there can be multiple newcategory related to mastercategory. Other relations are same as above explanation.
If you want to change this default related name then look at related_name, you can define it inside models.ForeignKey()
I want all my models to have SlugField however it seems like its not a DRY principle for each and every model to have:
slug = models.SlugField(max_length=50)
I want to implement this as follows:
Base Model
class BaseModel(models.Model):
created = models.DateTimeField(auto_now_add=True)
modified = models.DateTimeField(auto_now=True)
slug = models.SlugField(max_length=50, unique=True)
class Meta:
abstract = True
Company Model
class Company(BaseModel):
code = models.CharField(max_length=2, primary_key=True)
name = models.CharField(max_length=50)
class Meta:
verbose_name_plural = 'Companies'
def __str__(self):
return self.name
My other models will inherit BaseModel to have those fields inherited however, whenever I save new record, SlugField is empty. Anyone could enlighten me on this please!
I am new to Django (and databases for that matter) and trying to create a simple inventory application to help learn. I've been through the tutorials and am going through some books, but I am stuck at what i think is simple, just not sure where to look or how to ask.
With an inventory application, you have your equipment which then has a manufacturer, which the equipment has a model number that only that manufacturer has. Lets say Dell Optiplex 3040. I am also using the admin console right now as well. So i would like to be able to relate equipment to a manufacturer and then also relate the equipment to the model number. It almost seems as I am needing to use the many to many field and the through field to accomplish what I am trying to do but I dont think that is the right way to do it (shown in the link below). https://docs.djangoproject.com/en/1.9/topics/db/models/#many-to-many-relationships
Below is the code I have so far. Thank you.
from django.db import models
# Create your models here.
class Department(models.Model):
department = models.CharField(max_length=50)
def __str__(self):
return self.department
class Manufacturer(models.Model):
manufacturer = models.CharField(max_length=50)
def __str__(self):
return self.manufacturer
class EquipmentModel(models.Model):
equipmentModel = models.CharField(max_length=50)
def __str__(self):
return self.equipmentModel
class Employees(models.Model):
employee_name_first = models.CharField(max_length=25)
employee_name_last = models.CharField(max_length=25)
employee_username = models.CharField(max_length=20)
phone = models.IntegerField()
assigned_equipment = models.ForeignKey('Device', default='undefined')
department = models.ForeignKey('Department', on_delete=models.CASCADE, default='undefined')
job_title = models.ManyToManyField('Job_Positions', default='undefined')
def __str__(self):
return self.employee_username
class Device(models.Model):
ip = models.GenericIPAddressField(protocol='IPv4',unpack_ipv4=False,null=True, blank=True)#might be good to seperate IP in its own class because a device can have multiple IP's
department = models.ForeignKey('Department', on_delete=models.CASCADE)
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
serial_number = models.CharField(max_length=50)
date_created = models.DateTimeField(auto_now=False, auto_now_add=True)
date_updated = models.DateTimeField(auto_now=True, auto_now_add=False)
comments = models.TextField(blank=True)
def __str__(self):
return self.serial_number
class Job_Positions(models.Model):
position_title = models.CharField(max_length=50)
position_description = models.TextField(blank=True)
def __str__(self):
return position_title
***Edit to add the updated code and the admin.py code in response question I had to answer.
#admin.py
from django.contrib import admin
# Register your models here.
from .models import Device,Department,Manufacturer,Employees, Job_Positions, EquipmentModel
class DeviceModelAdmin(admin.ModelAdmin):
list_display = ["ip", "department","model","serial_number","date_updated"]
list_filter = ["department","model","ip"]
search_fields = ["ip"]
class Meta:
model = Device
class EmployeesModelAdmin(admin.ModelAdmin):
list_display = ["employee_name_first", "employee_name_last", "employee_username", "phone"]
list_filter = ["department"]
class Meta:
model = Employees
admin.site.register(Device, DeviceModelAdmin)
admin.site.register(Department)
admin.site.register(Manufacturer)
admin.site.register(EquipmentModel)
admin.site.register(Employees, EmployeesModelAdmin)
admin.site.register(Job_Positions)
updated models.py
from django.db import models
# Create your models here.
class Department(models.Model):
department = models.CharField(max_length=50)
def __str__(self):
return self.department
class Manufacturer(models.Model):
manufacturer = models.CharField(max_length=50)
def __str__(self):
return self.manufacturer
class EquipmentModel(models.Model):
model_number = models.CharField(max_length=50)
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
def __str__(self):
return self.model_number
class Employees(models.Model):
employee_name_first = models.CharField(max_length=25)
employee_name_last = models.CharField(max_length=25)
employee_username = models.CharField(max_length=20)
phone = models.IntegerField()
assigned_equipment = models.ForeignKey('Device', default='undefined')
department = models.ForeignKey('Department', on_delete=models.CASCADE, default='undefined')
job_title = models.ManyToManyField('Job_Positions', default='undefined')
def __str__(self):
return self.employee_username
class Device(models.Model):
ip = models.GenericIPAddressField(protocol='IPv4',unpack_ipv4=False,null=True, blank=True)#might be good to seperate IP in its own class because a device can have multiple IP's
department = models.ForeignKey('Department', on_delete=models.CASCADE)
model = models.ForeignKey('EquipmentModel', on_delete=models.CASCADE,null=True)
serial_number = models.CharField(max_length=50)
date_created = models.DateTimeField(auto_now=False, auto_now_add=True)
date_updated = models.DateTimeField(auto_now=True, auto_now_add=False)
comments = models.TextField(blank=True)
def __str__(self):
return self.serial_number
class Job_Positions(models.Model):
position_title = models.CharField(max_length=50)
position_description = models.TextField(blank=True)
def __str__(self):
return position_title
A many-to-many relationship is not what you want here, because any piece of equipment (I assume) can only have one manufacturer.
You do need an intermediate model which stores the model information, and you already have one in your EquipmentModel. I would suggest modifying it as follows:
class EquipmentModel(models.Model):
# This stores information about a particular model of device
manufacturer = models.ForeignKey('Manufacturer', on_delete=models.CASCADE)
model_number = models.CharField(max_length=50)
And then instead of having a foreign key to the manufacturer in Device, replace it with a foreign key to the equipment model:
class Device(models.Model):
# ...
model = models.ForeignKey('EquipmentModel', on_delete=models.CASCADE)