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import random
import string
import uuid
from django.core.exceptions import ValidationError
from django.db import models
from django.utils import timezone
class AuthorManager(models.Manager):
"""
Used to enable the get_by_natural_key method.
NOTE: Manager classes are only required to enable
using the natural key functionality of ForeignKeyWidget
"""
def get_by_natural_key(self, name):
"""
Django pattern function for finding an author by its name
"""
return self.get(name=name)
class Author(models.Model):
objects = AuthorManager()
name = models.CharField(max_length=100)
birthday = models.DateTimeField(default=timezone.now)
def natural_key(self):
"""
Django pattern function for serializing a model by its natural key
Used only by the ForeignKeyWidget using use_natural_foreign_keys.
"""
return (self.name,)
def __str__(self):
return self.name
def full_clean(self, exclude=None, validate_unique=True):
super().full_clean(exclude, validate_unique)
if exclude is None:
exclude = []
else:
exclude = list(exclude)
if "name" not in exclude and self.name == "123":
raise ValidationError({"name": "'123' is not a valid value"})
class Category(models.Model):
name = models.CharField(
max_length=100,
unique=True,
)
def __str__(self):
return self.name
class Meta:
verbose_name_plural = "categories"
class BookManager(models.Manager):
"""
Added to enable get_by_natural_key method
NOTE: Manager classes are only required to enable
using the natural key functionality of ForeignKeyWidget
"""
def get_by_natural_key(self, name, author):
"""
Django pattern function for returning a book by its natural key
"""
return self.get(name=name, author=Author.objects.get_by_natural_key(author))
class Book(models.Model):
objects = BookManager()
name = models.CharField("Book name", max_length=100)
author = models.ForeignKey(Author, blank=True, null=True, on_delete=models.CASCADE)
author_email = models.EmailField("Author email", max_length=75, blank=True)
imported = models.BooleanField(default=False)
published = models.DateField("Published", blank=True, null=True)
published_time = models.TimeField("Time published", blank=True, null=True)
price = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
added = models.DateTimeField(blank=True, null=True)
categories = models.ManyToManyField(Category, blank=True)
def natural_key(self):
"""
Django pattern function for serializing a book by its natural key.
Used only by the ForeignKeyWidget using use_natural_foreign_keys.
"""
return (self.name,) + self.author.natural_key()
natural_key.dependencies = ["core.Author"]
def __str__(self):
return self.name
class Parent(models.Model):
name = models.CharField(max_length=100)
def __str__(self):
return self.name
class Child(models.Model):
parent = models.ForeignKey(Parent, on_delete=models.CASCADE)
name = models.CharField(max_length=100)
def __str__(self):
return f"{self.name} - child of {self.parent.name}"
class Profile(models.Model):
user = models.OneToOneField("auth.User", on_delete=models.CASCADE)
is_private = models.BooleanField(default=True)
class Entry(models.Model):
user = models.ForeignKey("auth.User", on_delete=models.CASCADE)
class Role(models.Model):
user = models.OneToOneField("auth.User", on_delete=models.CASCADE, null=True)
class Person(models.Model):
role = models.ForeignKey(Role, on_delete=models.CASCADE)
class WithDefault(models.Model):
name = models.CharField("Default", max_length=75, blank=True, default="foo_bar")
def random_name():
chars = string.ascii_lowercase
return "".join(random.SystemRandom().choice(chars) for _ in range(100))
class WithDynamicDefault(models.Model):
name = models.CharField("Dyn Default", max_length=100, default=random_name)
class WithFloatField(models.Model):
f = models.FloatField(blank=True, null=True)
class EBook(Book):
"""Book proxy model to have a separate admin url access and name"""
class Meta:
proxy = True
class NamedAuthor(models.Model):
"""Class with a named primary key"""
name = models.CharField(max_length=256, primary_key=True)
class UUIDCategory(models.Model):
catid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
name = models.CharField(max_length=32)
def __str__(self):
return self.name
class Meta:
verbose_name_plural = "UUID categories"
class UUIDBook(models.Model):
"""A model which uses a UUID pk (issue 1274)"""
id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
name = models.CharField("Book name", max_length=100)
author = models.ForeignKey(
NamedAuthor, blank=True, null=True, on_delete=models.CASCADE
)
categories = models.ManyToManyField(UUIDCategory, blank=True)
def __str__(self):
return self.name
class WithPositiveIntegerFields(models.Model):
big = models.PositiveBigIntegerField(null=True)
small = models.PositiveSmallIntegerField(null=True)
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