一 . 需求
仿照Django中的admin , 开发了自己的stark组件,实现类似数据库客户端的功能,对数据进行增删改查 .
二 . 实现思路
1 . 在settings配置里分别注册三个APP
# Application definition INSTALLED_APPS = [ 'django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', 'app01.apps.App01Config', 'app02.apps.App02Config', 'stark.apps.StarkConfig', ] # (名字无所谓,叫stark纯属好记,清晰)
注 : python manage.py startapp app02 创建新项目(stark 同理)
2 . 在app01和app02的model文件中创建数据类型
app01/models.py
from django.db import models
# Create your models here.
from django.contrib.auth.models import AbstractUser
class UserInfo(models.Model):
"""
用户信息
"""
nid = models.AutoField(primary_key=True)
nickname = models.CharField(verbose_name='昵称', max_length=32)
telephone = models.CharField(max_length=11, null=True, unique=True)
avatar = models.FileField(upload_to = 'avatars/',default="/avatars/default.png")
create_time = models.DateTimeField(verbose_name='创建时间', auto_now_add=True)
blog = models.OneToOneField(to='Blog', to_field='nid',null=True)
def __str__(self):
return self.nickname
class Blog(models.Model):
"""
博客信息
"""
nid = models.AutoField(primary_key=True)
title = models.CharField(verbose_name='个人博客标题', max_length=64)
site = models.CharField(verbose_name='个人博客后缀', max_length=32, unique=True)
theme = models.CharField(verbose_name='博客主题', max_length=32)
#
# def __str__(self):
# return self.title
class Category(models.Model):
"""
博主个人文章分类表
"""
nid = models.AutoField(primary_key=True)
title = models.CharField(verbose_name='分类标题', max_length=32)
blog = models.ForeignKey(verbose_name='所属博客', to='Blog', to_field='nid')
def __str__(self):
return self.title
class Tag(models.Model):
nid = models.AutoField(primary_key=True)
title = models.CharField(verbose_name='标签名称', max_length=32)
blog = models.ForeignKey(verbose_name='所属博客', to='Blog', to_field='nid')
def __str__(self):
return self.title
class Article(models.Model):
nid = models.AutoField(primary_key=True)
title = models.CharField(max_length=50, verbose_name='文章标题')
desc = models.CharField(max_length=255, verbose_name='文章描述')
comment_count= models.IntegerField(default=0)
up_count = models.IntegerField(default=0)
down_count = models.IntegerField(default=0)
create_time = models.DateTimeField(verbose_name='创建时间')
homeCategory = models.ForeignKey(to='Category', to_field='nid', null=True)
#siteDetaiCategory = models.ForeignKey(to='SiteCategory', to_field='nid', null=True)
user = models.ForeignKey(verbose_name='作者', to='UserInfo', to_field='nid')
tags = models.ManyToManyField(
to="Tag",
through='Article2Tag',
through_fields=('article', 'tag'),
)
def __str__(self):
return self.title
class ArticleDetail(models.Model):
"""
文章详细表
"""
nid = models.AutoField(primary_key=True)
content = models.TextField()
article = models.OneToOneField(to='Article', to_field='nid')
class Article2Tag(models.Model):
nid = models.AutoField(primary_key=True)
article = models.ForeignKey(verbose_name='文章', to="Article", to_field='nid')
tag = models.ForeignKey(verbose_name='标签', to="Tag", to_field='nid')
class Meta:
unique_together = [
('article', 'tag'),
]
def __str__(self):
v=self.article.title+"----"+self.tag.title
return v
app01/models.py
app01/models.py
app02/models.py
from django.db import models
# Create your models here.
class Book(models.Model):
title=models.CharField(max_length=32,verbose_name="标题")
注 : python manage.py makemigrations (同步数据库)
python manage.py migrate
3 . 在（不确定每个）当前APP中的app.py文件中添加 目的：让项目一运行先把所有app里面所有叫stark的加载一遍
from django.apps import AppConfig
from django.utils.module_loading import autodiscover_modules
class AppConfig(AppConfig):
name = "app01"
def ready(self):
autodiscover_modules("stark",)
实现在Django项目启动时,扫描每个APP项目下的stark.py文件的文件, 执行其中的代码,注册每个APP下的model,为每个model生成增删改查四条URL.
流程图说明一切 (～￣▽￣)～
4 . 注册
仿照 admin 设置相关类,首先创建下面的文件
在执行 admin.py文件时我们发现其实第一步就是导入 admin,导入时通过单例模式生成一个 site 对象,现在我们也要写个类,生成一个单例对象 :
class StarkSite(object):
def __init__(self):
self._registry = {}
site = StarkSite()
在app01 和 app02 的 stark.py 文件中导入
from stark.service.stark import site
这样我们也就得到了一个单例对象 site, 在注册时 admin使用的是site对象的 register 方法,所以我们也要写一个 register 方法 .
class StarkSite(object):
def __init__(self):
self._registry={}
def register(self,model,modle_stark=None):
if not modle_stark:
modle_stark=ModelStark
self._registry[model]=modle_stark(model)
site = StarkSite()
这个方法的本质其实就是 往 self._registry 这个字典添加键值对,键--就是我们的数据类(如Book类),值--就是一个类的对象,这个类就是我们要创建的第二个类,样式类
class ModelStark(object):
def __init__(self, model, site):
self.model = model
self.site = site
注意 : self.model 指的是什么? self 指的是什么?
self : 当前访问模型表的配置类对象
self.model : 当前访问模型表(如 Book 表)
通过这个类我们可以控制页面展示的内容和样式
前戏完成之后我们就可以在app01 和app02的stark.py文件中开始注册了
#app01
from stark.service.stark import site
from .models import *
class UserInfoConfig(ModelStark):
list_display = ["nickname", "telephone"]
site.register(UserInfo,UserInfoConfig)
site.register(Blog)
site.register(Article)
site.register(Category)
site.register(Tag)
#app02
from stark.service.stark import site
from .models import *
class BookConfig(ModelStark):
list_display = ["title"]
site.register(Book,BookConfig)
注册完成后,我们的 site._registry字典中就有了我们注册类对应的键值对.
5 . URL配置
admin 中的URL配置
from django.conf.urls import url
from django.contrib import admin
urlpatterns = [
url(r'^admin/', admin.site.urls),
]
我们可以看出来,所有的 url 都是在admin.site.urls 这个方法中生成的,看看源码 :
@property
def urls(self):
return self.get_urls(), 'admin', self.name
其实就是在做一个分发,url 是在 self.get_urls() 这个函数中,生成的,
def get_urls(self):
from django.conf.urls import url, include
# Since this module gets imported in the application's root package,
# it cannot import models from other applications at the module level,
# and django.contrib.contenttypes.views imports ContentType.
from django.contrib.contenttypes import views as contenttype_views
def wrap(view, cacheable=False):
def wrapper(*args, **kwargs):
return self.admin_view(view, cacheable)(*args, **kwargs)
wrapper.admin_site = self
return update_wrapper(wrapper, view)
# Admin-site-wide views.
urlpatterns = [
url(r'^$', wrap(self.index), name='index'),
url(r'^login/$', self.login, name='login'),
url(r'^logout/$', wrap(self.logout), name='logout'),
url(r'^password_change/$', wrap(self.password_change, cacheable=True), name='password_change'),
url(r'^password_change/done/$', wrap(self.password_change_done, cacheable=True),
name='password_change_done'),
url(r'^jsi18n/$', wrap(self.i18n_javascript, cacheable=True), name='jsi18n'),
url(r'^r/(?P<content_type_id>d+)/(?P<object_id>.+)/$', wrap(contenttype_views.shortcut),
name='view_on_site'),
]
# Add in each model's views, and create a list of valid URLS for the
# app_index
valid_app_labels = []
for model, model_admin in self._registry.items():
urlpatterns += [
url(r'^%s/%s/' % (model._meta.app_label, model._meta.model_name), include(model_admin.urls)),
]
if model._meta.app_label not in valid_app_labels:
valid_app_labels.append(model._meta.app_label)
# If there were ModelAdmins registered, we should have a list of app
# labels for which we need to allow access to the app_index view,
if valid_app_labels:
regex = r'^(?P<app_label>' + '|'.join(valid_app_labels) + ')/$'
urlpatterns += [
url(regex, wrap(self.app_index), name='app_list'),
]
return urlpatterns
这里我们知道我们要生成的url的格式都是 admin/app名/表名, 所以我们要想办法取到 app名和表名在拼接起来.
for model, model_admin in self._registry.items():
urlpatterns += [
url(r'^%s/%s/' % (model._meta.app_label, model._meta.model_name), include(model_admin.urls)),
]
这里的 model 就是我们的数据类(如 Book )
model._meta.app_label 取类所在的app名
model._meta.model_name 取类的名字
这样我们就成功拼接出了我们要的url，但是每个url下又有增删改查不同的url，这时又要再次进行分发，admin中使用了include方法，通过model_admin我们注册时样式类生成的对象下的url方法得到我们想要的
def get_urls(self):
from django.conf.urls import url
def wrap(view):
def wrapper(*args, **kwargs):
return self.admin_site.admin_view(view)(*args, **kwargs)
wrapper.model_admin = self
return update_wrapper(wrapper, view)
info = self.model._meta.app_label, self.model._meta.model_name
urlpatterns = [
url(r'^$', wrap(self.changelist_view), name='%s_%s_changelist' % info),
url(r'^add/$', wrap(self.add_view), name='%s_%s_add' % info),
url(r'^(.+)/history/$', wrap(self.history_view), name='%s_%s_history' % info),
url(r'^(.+)/delete/$', wrap(self.delete_view), name='%s_%s_delete' % info),
url(r'^(.+)/change/$', wrap(self.change_view), name='%s_%s_change' % info),
# For backwards compatibility (was the change url before 1.9)
url(r'^(.+)/$', wrap(RedirectView.as_view(
pattern_name='%s:%s_%s_change' % ((self.admin_site.name,) + info)
))),
]
return urlpatterns
@property
def urls(self):
return self.get_urls()
其实和之前一样，只是做了又一次分发，并且对应了视图函数，这里我们先不看视图函数的内容，值得注意的是这一次的分发和视图函数都是写在样式类中的，而不是写在生成site的AdminStie类中
这样有什么好处呢，我们知道当我们要注册时，是可以自己定义一些属性的，其实要显示的页面也是可以自己定义的，所以讲这最后一层url分发和对应的函数写在样式类中可以方便我们进行自定义
stark 配置
首先在 urls 文件中配置
from django.conf.urls import url
from django.contrib import admin
from stark.service.stark import site
urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^stark/', site.urls),
]
然后在我们 sites.py文件中添加相关代码.简写
from django.conf.urls import url
from django.shortcuts import HttpResponse, render
class ModelStark(object):
def __init__(self, model, site):
self.model = model
self.site = site
def change_list(self, request):
ret = self.model.objects.all()
return render(request, "stark/change_list.html", locals())
def add_view(self, request):
return HttpResponse("add_view")
def del_view(self, request, id):
return HttpResponse("del_view")
def change_view(self, request, id):
return HttpResponse("change_view")
def get_url_func(self):
temp = []
temp.append(url("^$", self.change_list))
temp.append(url("^add/$", self.add_view))
temp.append(url("^(d+)/delete/$", self.del_view))
temp.append(url("^(d+)/change/$", self.change_view))
return temp
@property
def urls(self):
return self.get_url_func(), None, None
class StarkSite(object):
def __init__(self):
self._registry = {}
def register(self, model, model_config=None):
if not model_config:
model_config = ModelStark
self._registry[model] = model_config(model, self)
def get_urls(self):
temp = []
for model, model_config in self._registry.items():
model_name = model._meta.model_name
app_label = model._meta.app_label
u = url("^%s/%s/" % (app_label, model_name), model_config.urls)
temp.append(u)
return temp
@property
def urls(self):
return self.get_urls(), None, None
site = StarkSite()
反向解析,别名的使用.
在设置url对应的视图函数时,我们可以给这个url添加一个别名,在使用时可以通过这个别名反向生成url,这样既可以使url有修改,只要别名不变我们就不用修改代码.
增加别名时要注意 : 由于每一个数据类都生成增删改查四条url,所以在写别名的时候应该有区别,不然会引起混淆,所以我们设计别名的格式应该是 -- app名_表名_*
def get_url_func(self):
temp = []
model_name = self.model._meta.model_name
app_label = self.model._meta.app_label
app_model = (app_label, model_name)
temp.append(url("^$", self.change_list, name="%s_%s_list" % app_model))
temp.append(url("^add/$", self.add_view, name="%s_%s_add" % app_model))
temp.append(url("^(d+)/delete/$", self.del_view, name="%s_%s_delete" % app_model))
temp.append(url("^(d+)/change/$", self.change_view, name="%s_%s_change" % app_model))
return temp
@property
def urls(self):
return self.get_url_func(), None, None
list_display_links
def new_list_display(self):
temp=[]
temp.append(ModelStark.checkbox)
temp.extend(self.list_display)#把数据打散，用append是把整个列表放进去
#---------------------有list_display_links则不显示编辑字段
if not self.list_display_links:
temp.append(ModelStark.edit)
print('sssssssssssssssssssssssssssss',self.list_display_links)
temp.append(ModelStark.deletes)
return temp
新语法
from app1.models import Book
obj = Book._meta.get_field("title")
# obj 为 一个field 对象 打印结果： <django.db.models.fields.CharField: title>
print(obj.verbose_name)
# 默认打印为“title” ，如果模型类中设置为该字段设置了，verbose_name="书籍名称”
#则会打印书籍名称