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from datetime import datetime
from django.db import models
# M2M described on one of the models
class Person(models.Model):
name = models.CharField(max_length=128)
class Meta:
ordering = ("name",)
class PersonChild(Person):
pass
class Group(models.Model):
name = models.CharField(max_length=128)
members = models.ManyToManyField(Person, through="Membership")
custom_members = models.ManyToManyField(
Person, through="CustomMembership", related_name="custom"
)
nodefaultsnonulls = models.ManyToManyField(
Person,
through="TestNoDefaultsOrNulls",
related_name="testnodefaultsnonulls",
)
class Meta:
ordering = ("name",)
class Membership(models.Model):
person = models.ForeignKey(Person, models.CASCADE)
group = models.ForeignKey(Group, models.CASCADE)
date_joined = models.DateTimeField(default=datetime.now)
invite_reason = models.CharField(max_length=64, null=True)
class Meta:
ordering = ("date_joined", "invite_reason", "group")
def __str__(self):
return "%s is a member of %s" % (self.person.name, self.group.name)
class CustomMembership(models.Model):
person = models.ForeignKey(
Person,
models.CASCADE,
db_column="custom_person_column",
related_name="custom_person_related_name",
)
group = models.ForeignKey(Group, models.CASCADE)
weird_fk = models.ForeignKey(Membership, models.SET_NULL, null=True)
date_joined = models.DateTimeField(default=datetime.now)
class Meta:
db_table = "test_table"
ordering = ["date_joined"]
def __str__(self):
return "%s is a member of %s" % (self.person.name, self.group.name)
class TestNoDefaultsOrNulls(models.Model):
person = models.ForeignKey(Person, models.CASCADE)
group = models.ForeignKey(Group, models.CASCADE)
nodefaultnonull = models.IntegerField()
class PersonSelfRefM2M(models.Model):
name = models.CharField(max_length=5)
friends = models.ManyToManyField("self", through="Friendship", symmetrical=False)
sym_friends = models.ManyToManyField(
"self", through="SymmetricalFriendship", symmetrical=True
)
class Friendship(models.Model):
first = models.ForeignKey(
PersonSelfRefM2M, models.CASCADE, related_name="rel_from_set"
)
second = models.ForeignKey(
PersonSelfRefM2M, models.CASCADE, related_name="rel_to_set"
)
date_friended = models.DateTimeField()
class SymmetricalFriendship(models.Model):
first = models.ForeignKey(PersonSelfRefM2M, models.CASCADE)
second = models.ForeignKey(PersonSelfRefM2M, models.CASCADE, related_name="+")
date_friended = models.DateField()
# Custom through link fields
class Event(models.Model):
title = models.CharField(max_length=50)
invitees = models.ManyToManyField(
to=Person,
through="Invitation",
through_fields=["event", "invitee"],
related_name="events_invited",
)
class Invitation(models.Model):
event = models.ForeignKey(Event, models.CASCADE, related_name="invitations")
# field order is deliberately inverted. the target field is "invitee".
inviter = models.ForeignKey(Person, models.CASCADE, related_name="invitations_sent")
invitee = models.ForeignKey(Person, models.CASCADE, related_name="invitations")
class Employee(models.Model):
name = models.CharField(max_length=5)
subordinates = models.ManyToManyField(
"self",
through="Relationship",
through_fields=("source", "target"),
symmetrical=False,
)
class Meta:
ordering = ("pk",)
class Relationship(models.Model):
# field order is deliberately inverted.
another = models.ForeignKey(
Employee, models.SET_NULL, related_name="rel_another_set", null=True
)
target = models.ForeignKey(Employee, models.CASCADE, related_name="rel_target_set")
source = models.ForeignKey(Employee, models.CASCADE, related_name="rel_source_set")
class Ingredient(models.Model):
iname = models.CharField(max_length=20, unique=True)
class Meta:
ordering = ("iname",)
class Recipe(models.Model):
rname = models.CharField(max_length=20, unique=True)
ingredients = models.ManyToManyField(
Ingredient,
through="RecipeIngredient",
related_name="recipes",
)
class Meta:
ordering = ("rname",)
class RecipeIngredient(models.Model):
ingredient = models.ForeignKey(Ingredient, models.CASCADE, to_field="iname")
recipe = models.ForeignKey(Recipe, models.CASCADE, to_field="rname")
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