python之Django 後臺管理系統(模型層)

一.項目文件路徑

1.在項目路徑下新建python_package，取名apps，然後新建app名rbacs

<code>startapp   rbacs/<code>

目錄結構

2.model.py新建要使用的model層(也就是我們經常說的數據庫結構)

<code>from datetime import datetime

from django.contrib.auth.models import AbstractUser
from django.db import models
from apps.utils.common import Utils


class Menu(models.Model):
    """    菜單    """    menu_code = models.CharField(max_length=50, unique=True, verbose_name="菜單編號")
    menu_name = models.CharField(max_length=100, verbose_name="菜單名稱")
    table_name = models.CharField(max_length=50, verbose_name="表名", default='', blank=True)
    desc = models.CharField(max_length=100, verbose_name="描述", default='', blank=True)
    icon = models.CharField(max_length=100, default='', blank=True, verbose_name="圖標")
    sort = models.IntegerField(default=0, verbose_name="排序")
    parent = models.ForeignKey('self', on_delete=models.CASCADE, null=True, blank=True,                               verbose_name="上級菜單")
    is_last = models.CharField(max_length=10, choices=(("T", "一級"), ("M", "二級"), ("L", "三級")), verbose_name="層級",                               default="T")
    is_out = models.BooleanField(default=False, verbose_name="跨域否")
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "菜單表"        verbose_name_plural = verbose_name

    def __str__(self):
        name_list = [self.menu_name]
        p = self.parent
        while p:
            name_list.insert(0, p.menu_name)
            p = p.parent
        return "-".join(name_list)


class Accession(models.Model):
    """    權限(URL)    """    url = models.CharField(max_length=500, verbose_name="鏈接(url)", default='', blank=True)
    desc = models.CharField(max_length=100, verbose_name="名稱", default='', blank=True)
    menu = models.ForeignKey(Menu, on_delete=models.CASCADE, verbose_name="菜單")
    is_menu = models.BooleanField(default=False, verbose_name="菜單顯示")
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "權限表"        verbose_name_plural = verbose_name
        unique_together = ('url', 'menu')

    def __str__(self):
        return '{menu}:{url}'.format(menu=self.menu.menu_name, url=self.url)


class Action(models.Model):
    """    操作碼    """    action_code = models.CharField(max_length=50, verbose_name="操作編號")
    action_name = models.CharField(max_length=100, verbose_name="操作名稱")
    accession = models.ForeignKey(Accession, on_delete=models.CASCADE, verbose_name="權限菜單", null=True, blank=True)
    desc = models.TextField(verbose_name="描述", default='', blank=True)
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "操作碼錶"        verbose_name_plural = verbose_name
        unique_together = ('action_code', 'accession')

    def __str__(self):
        return '{code}:{name}'.format(code=self.action_code, name=self.action_name)


class Role(models.Model):
    """    角色    """    role_code = models.CharField(max_length=50, unique=True, verbose_name="角色編號")
    role_name = models.CharField(max_length=100, verbose_name="角色名稱")
    desc = models.TextField(verbose_name="描述", default='', blank=True)
    # 定義角色和權限（URL)的多對多關係    accessions = models.ManyToManyField(Accession, verbose_name="權限", related_name="role", blank=True)
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "角色表"        verbose_name_plural = verbose_name

    def __str__(self):
        return '{code}:{name}'.format(code=self.role_code, name=self.role_name)


class Role2Accession2Action(models.Model):
    """    角色權限操作碼    """    role = models.ForeignKey(Role, on_delete=models.CASCADE, verbose_name="角色")
    accession = models.ForeignKey(Accession, on_delete=models.CASCADE, verbose_name="權限")
    action = models.ForeignKey(Action, on_delete=models.CASCADE, verbose_name="操作碼")
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "角色權限操作碼錶"        verbose_name_plural = verbose_name
        unique_together = ('role', 'accession', 'action')

    def __str__(self):
        return '{role}:{accession}:{action}'.format(role=self.role.role_name, accession=self.accession.url,                                                    action=self.action.action_name)


class UserProfile(AbstractUser):
    """    自定義用戶    """    nick_name = models.CharField(max_length=50, verbose_name="暱稱", default="小親親", blank=True)
    birthday = models.DateField(verbose_name="生日", null=True, blank=True)
    gender = models.CharField(max_length=2, verbose_name="性別", choices=(("F", "女"), ("M", "男")))
    address = models.CharField(max_length=100, verbose_name="地址", default='', blank=True)
    mobile = models.CharField(max_length=11, verbose_name="手機號碼", default='', blank=True)
    image = models.ImageField(verbose_name="用戶頭像", upload_to="head_image/%Y/%m", default="head_image/default.png",                              help_text="114x113")
    employee = models.OneToOneField('bases.Employee', on_delete=models.CASCADE, related_name="user_employee",                                    blank=True, null=True)
    plants = models.ManyToManyField('bases.plant', verbose_name="所屬工廠", related_name="user_plant", blank=True)
    add_time = models.DateTimeField(auto_now_add=True, verbose_name="添加時間")
    upd_time = models.DateTimeField(default=datetime.now, verbose_name="更新時間")

    class Meta:
        verbose_name = "用戶表"        verbose_name_plural = verbose_name

    def __str__(self):
        if self.nick_name:
            return '{name}:{nick_name}'.format(name=self.username, nick_name=self.nick_name)
        return self.username

    def full_name(self):
        if self.last_name and self.first_name:
            return '{last_name}{first_name}'.format(last_name=self.last_name, first_name=self.first_name)
        return None    full_name.short_description = "姓名"
3.model 層知識點介紹
 3.1新建完app 後一定要在setting 文件下添加app，否則無法做makemigrations 和migrate。
INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'apps.rbacs.apps.RbacsConfig',
]
3.2 一對多(多對一)
顧名思義，一對多，即是一條數據對多條數據。如上述model 中的 Menu 和Accession就是一對多的關係，理解成數據庫結構就是Menu 是Accession的外鍵
 menu = models.ForeignKey(Menu, on_delete=models.CASCADE, verbose_name="菜單")
CASCADE 的意思就是Menu 數據刪除了，那麼Accession 的數據也同時被刪除
DO_NOTHING 就是刪除了menu 數據，accession 的數據不受影響
限於篇幅限制，下篇繼續。
/<code>