yp_library.models 源代码

from django.db import models
from django.contrib import admin
from generic.models import User

__all__ = [
    "User",
    "Reader",
    "Book",
    "LendRecord",
]




class Reader(models.Model):
    class Meta:
        verbose_name = "读者"
        verbose_name_plural = verbose_name

    id = models.AutoField("编号", primary_key=True)
    student_id = models.CharField("学号", max_length=30, blank=True, null=True)

    def __str__(self):
        return self.student_id





class Book(models.Model):
    class Meta:
        verbose_name = "书"
        verbose_name_plural = verbose_name

    id = models.IntegerField("书籍编号", primary_key=True)
    identity_code = models.CharField("索书号",
                                     max_length=254,
                                     blank=True,
                                     null=True)
    title = models.CharField("书名", max_length=500, blank=True, null=True)
    author = models.CharField("作者", max_length=254, blank=True, null=True)
    publisher = models.CharField("出版商", max_length=254, blank=True, null=True)
    returned = models.BooleanField("是否已还", default=True)

    def __str__(self):
        return str(self.title)





class LendRecord(models.Model):
    class Meta:
        verbose_name = "借阅记录"
        verbose_name_plural = verbose_name
        ordering = ["-lend_time"]

    id = models.IntegerField("条目编号", primary_key=True)
    reader_id = models.ForeignKey(Reader,
                                  on_delete=models.CASCADE,
                                  verbose_name="读者编号")
    book_id = models.ForeignKey(Book,
                                on_delete=models.SET_NULL,
                                verbose_name="书籍编号",
                                blank=True,
                                null=True)
    lend_time = models.DateTimeField("借出时间")
    due_time = models.DateTimeField("还书截止时间")
    return_time = models.DateTimeField("还书时间", blank=True, null=True)
    returned = models.BooleanField("是否已还", default=False)



    class Status(models.IntegerChoices):
        NORMAL = (0, "正常")
        OVERTIME = (1, "超时扣分")
        APPEALING = (2, "申诉中")
        ACCEPTED = (3, "申诉通过")
        REJECTED = (4, "申诉失败")


    status = models.SmallIntegerField("借阅记录状态",
                                      choices=Status.choices,
                                      default=Status.NORMAL)



    def get_admin_url(self) -> str:
        '''获取后台搜索的url'''
        return f'/admin/yp_library/lendrecord/?q={self.id}'




    @admin.display(description="读者学号")
    def reader_stu_id(self):
        return self.reader_id.student_id




    @admin.display(description="书籍名称")
    def book_name(self):
        if self.book_id:
            return self.book_id.title
        else:
            return "未知"