У меня есть две модели, показанные ниже.Я хочу иметь возможность выполнить этот запрос через ORM django, по сути, предоставив мне класс CustomUser вместе с двумя производными полями: max (message.sent_at) и max (случай, когда read_at равен нулю, а затем 1 или 0 заканчиваются).Эти два поля позволят мне сортировать потоки сообщений по именам пользователей и последним действиям.
Вот мои классы:
class CustomUser(AbstractBaseUser, PermissionsMixin):
username_validator = UnicodeUsernameValidator()
username = models.CharField(_('username'), max_length=150, unique=True, help_text=_('Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only.'), validators=[username_validator], error_messages={'unique': _('A user with that username already exists.'),},)
email = models.EmailField(_('email address'), blank=True)
first_name = models.CharField(_('first name'), max_length=30, blank=True)
last_name = models.CharField(_('last name'), max_length=150, blank=True)
is_staff = models.BooleanField(_('staff status'), default=False, help_text=_('Designates whether the user can log into this admin site.'),)
is_active = models.BooleanField(_('active'), default=True, help_text=_('Designates whether this user should be treated as active. Unselect this instead of deleting accounts.'),)
date_joined = models.DateTimeField(_('date joined'), default=timezone.now)
bio = models.TextField(max_length=500, null=True, blank=True)
location = models.CharField(max_length=30, null=True, blank=True)
birth_date = models.DateField(null=True, blank=True)
phone_number = PhoneNumberField(default='+10000000000')
gender = models.CharField(max_length=32, choices=[(tag.name, tag.value) for tag in GenderChoice], default=GenderChoice.UNSPECIFIED.value)
objects = UserManager()
EMAIL_FIELD = 'email'
USERNAME_FIELD = 'username'
REQUIRED_FIELDS = ['email']
class Meta:
ordering = ['username']
verbose_name = _('user')
verbose_name_plural = _('users')
и
class Message(AbstractIP):
subject = models.CharField(_('Subject'), max_length=120, blank=True)
body = models.TextField(_('Body')) # Do we want to cap length or enforce non-blank?
sender = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='sender_messages', verbose_name=_('Sender'), on_delete=models.CASCADE)
recipient = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='receiver_messages', verbose_name=_('Recipient'), blank=True, on_delete=models.CASCADE)
parent_msg = models.ForeignKey('self', related_name='next_messages', null=True, blank=True, verbose_name=_('Parent message'), on_delete=models.CASCADE)
sent_at = models.DateTimeField(_('sent at'), null=True, blank=True)
read_at = models.DateTimeField(_('read at'), null=True, blank=True)
replied_at = models.DateTimeField(_('replied at'), null=True, blank=True)
sender_deleted_at = models.DateTimeField(_('Sender deleted at'), null=True, blank=True)
recipient_deleted_at = models.DateTimeField(_('Recipient deleted at'), null=True, blank=True)
ip = models.GenericIPAddressField(verbose_name=_('IP'), null=True, blank=True)
user_agent = models.CharField(verbose_name=_('User Agent'), blank=True, max_length=255)
objects = MessageManager() # Manager for Message queries
def new(self):
"""Returns whether the recipient has read the message or not"""
if self.read_at is not None:
return False
return True
def replied(self):
"""Returns whether the recipient has written a reply to this message"""
if self.replied_at is not None:
return True
return False
def __str__(self):
if self.subject is not None:
return self.subject
if self.body is not None:
return self.body[:40]
return None
def get_absolute_url(self):
return reverse('messages_detail', args=[self.id])
def save(self, **kwargs):
if not self.id:
self.sent_at = timezone.now()
super(Message, self).save(**kwargs)
class Meta:
ordering = ['-sent_at']
verbose_name = _('Message')
verbose_name_plural = _('Messages')
Запрос Iхочу быть в состоянии выполнить приравнивает это, но я не могу понять, как это сделать в ORM, где% s является заполнителем для поля CustomUser.id (pk) данного пользователя.
SELECT webrtc_customuser.*
,MAX(webrtc_message.sent_at) AS sent_at
,MAX(CASE WHEN webrtc_message.read_at IS NULL AND webrtc_customuser.id <> webrtc_message.sender_id THEN 1 ELSE 0 END) AS has_unread
FROM webrtc_customuser
INNER JOIN webrtc_message
ON (
webrtc_customuser.id = webrtc_message.sender_id
AND webrtc_message.sender_id = %s
AND webrtc_message.sender_deleted_at IS NULL
) OR (
webrtc_customuser.id = webrtc_message.recipient_id
AND webrtc_message.recipient_id = %s
AND webrtc_message.recipient_deleted_at IS NULL
)
Мне удалось получить правильный user_id и производные поля со следующими запросами, но я не могу понять, как соединить свойства CustomUser вместе с ними.
messages = self.values(
user_fk=Case(When(sender=user, then='recipient'), default='sender', output_field=models.IntegerField())
).exclude(
sender=user, recipient=user
).filter(
Q(sender=user, sender_deleted_at__isnull=True) |
Q(recipient=user, recipient_deleted_at__isnull=True)
).annotate(
max_sent_at=Max('sent_at'),
has_unread=Max(Case(When(~Q(sender=user) & Q(read_at__isnull=True), then=1), default=0, output_field=models.IntegerField()))
).order_by()
Заранее спасибо за ваше время!
Редактировать: обновленный запрос ORM