factory/apps/utils/models.py

import django.utils.timezone as timezone
from django.db import models
from django.db.models.query import QuerySet

from apps.utils.snowflake import idWorker


# 自定义软删除查询基类


class SoftDeletableQuerySetMixin(object):
    '''
    QuerySet for SoftDeletableModel. Instead of removing instance sets
    its ``is_deleted`` field to True.
    '''

    def delete(self, soft=True, update_by=None):
        '''
        Soft delete objects from queryset (set their ``is_deleted``
        field to True)
        '''
        if soft:
            self.update(is_deleted=True, update_by=update_by)
        else:
            return super(SoftDeletableQuerySetMixin, self).delete()


class SoftDeletableQuerySet(SoftDeletableQuerySetMixin, QuerySet):
    pass


class SoftDeletableManagerMixin(object):
    '''
    Manager that limits the queryset by default to show only not deleted
    instances of model.
    '''
    _queryset_class = SoftDeletableQuerySet

    def get_queryset(self, all=False):
        '''
        Return queryset limited to not deleted entries.
        '''
        kwargs = {'model': self.model, 'using': self._db}
        if hasattr(self, '_hints'):
            kwargs['hints'] = self._hints
        if all:
            return self._queryset_class(**kwargs)
        return self._queryset_class(**kwargs).filter(is_deleted=False)


class SoftDeletableManager(SoftDeletableManagerMixin, models.Manager):
    pass


class BaseModel(models.Model):
    """
    基本表
    """
    id = models.CharField(max_length=20, primary_key=True, default=idWorker.get_id, editable=False, verbose_name='主键ID', help_text='主键ID')
    create_time = models.DateTimeField(
        default=timezone.now, verbose_name='创建时间', help_text='创建时间')
    update_time = models.DateTimeField(
        auto_now=True, verbose_name='修改时间', help_text='修改时间')
    is_deleted = models.BooleanField(
        default=False, verbose_name='删除标记', help_text='删除标记')

    class Meta:
        abstract = True

    def save(self, *args, **kwargs):
        if self.pk:
            # If self.pk is not None then it's an update.
            cls = self.__class__
            old = cls.objects.filter(pk=self.pk).first()
            if old:
                # This will get the current model state since super().save() isn't called yet.
                new = self  # This gets the newly instantiated Mode object with the new values.
                changed_fields = []
                for field in cls._meta.get_fields():
                    field_name = field.name
                    try:
                        if getattr(old, field_name) != getattr(new, field_name):
                            changed_fields.append(field_name)
                    except Exception as ex:  # Catch field does not exist exception
                        pass
                kwargs['update_fields'] = changed_fields
        super().save(*args, **kwargs)
        
class SoftModel(BaseModel):
    """
    软删除基本表
    """
    class Meta:
        abstract = True

    objects = SoftDeletableManager()

    def delete(self, using=None, soft=True, update_by=None, *args, **kwargs):
        '''
        这里需要真删除的话soft=False即可
        '''
        if soft:
            self.is_deleted = True
            self.update_by = update_by
            self.save(using=using)
        else:

            return super(SoftModel, self).delete(using=using, *args, **kwargs)


class CommonAModel(SoftModel):
    """
    业务用基本表A,包含create_by, update_by字段
    """
    create_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='创建人', related_name= '%(class)s_create_by')
    update_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='最后编辑人', related_name= '%(class)s_update_by')

    class Meta:
        abstract = True

    

class CommonBModel(SoftModel):
    """
    业务用基本表B,包含create_by, update_by, belong_dept字段
    """
    create_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='创建人', related_name = '%(class)s_create_by')
    update_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='最后编辑人', related_name = '%(class)s_update_by')
    belong_dept = models.ForeignKey(
        'system.dept', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='所属部门', related_name= '%(class)s_belong_dept')

    class Meta:
        abstract = True

class CommonADModel(BaseModel):
    """
    业务用基本表A, 物理删除, 包含create_by, update_by字段
    """
    create_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='创建人', related_name= '%(class)s_create_by')
    update_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='最后编辑人', related_name= '%(class)s_update_by')

    class Meta:
        abstract = True

class CommonBDModel(BaseModel):
    """
    业务用基本表B, 物理删除, 包含create_by, update_by, belong_dept字段
    """
    create_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='创建人', related_name = '%(class)s_create_by')
    update_by = models.ForeignKey(
        'system.user', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='最后编辑人', related_name = '%(class)s_update_by')
    belong_dept = models.ForeignKey(
        'system.organzation', null=True, blank=True, on_delete=models.SET_NULL, verbose_name='所属部门', related_name= '%(class)s_belong_dept')

    class Meta:
        abstract = True