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一、Django           pip3 install django                 C:\Python35\Scripts           # 创建Django工程     django-admin startproject 【工程名称】               mysite             - mysite        # 对整个程序进行配置                 - init                 - settings  # 配置文件                 - url       # URL对应关系                 - wsgi      # 遵循WSIG规范，uwsgi + nginx             - manage.py     # 管理Django程序：                                 - python manage.py                                 - python manage.py startapp xx                                 - python manage.py makemigrations                                 - python manage.py migrate                                   # 运行Django功能     python manage.py runserver 127.0.0.1:8001                 chouti         - chouti             - 配置         - 主站 app         - 后台管理 app                       # 创建app     python manage.py startapp cmdb     python manage.py startapp openstack     python manage.py startapp xxoo....                 app：         migrations     数据修改表结构         admin          Django为我们提供的后台管理         apps           配置当前app         models         ORM,写指定的类  通过命令可以创建数据库结构         tests          单元测试         views          业务代码                       1、配置模板的路径               TEMPLATES = [                 {                     'BACKEND': 'django.template.backends.django.DjangoTemplates',                     'DIRS': [os.path.join(BASE_DIR, 'templates')],                     'APP_DIRS': True,                     'OPTIONS': {                         'context_processors': [                             'django.template.context_processors.debug',                             'django.template.context_processors.request',                             'django.contrib.auth.context_processors.auth',                             'django.contrib.messages.context_processors.messages',                         ],                     },                 },             ]     2、配置静态目录         static               STATICFILES_DIRS = (             os.path.join(BASE_DIR, 'static'),         )                     <link rel="stylesheet" href="/static/commons.css" />         内容整理     1. 创建Django工程             django-admin startproject 工程名       2. 创建APP         cd 工程名         python manage.py startapp cmdb       3、静态文件         project.settings.py                   STATICFILES_DIRS = (             os.path.join(BASE_DIR, "static"),         )           4、模板路径               DIRS ==>    [os.path.join(BASE_DIR,'templates'),]               5、settings中                   middlerware                       # 注释 csrf                                 6、定义路由规则         url.py                       "login" --> 函数名                   7、定义视图函数         app下views.py                           def func(request):                 # request.method   GET / POST                                   # http://127.0.0.1:8009/home?nid=123&name=alex                 # request.GET.get('',None)   # 获取请求发来的而数据                                   # request.POST.get('',None)                                                     # return HttpResponse("字符串")                 # return render(request, "HTML模板的路径")                 # return redirect('/只能填URL')                       8、模板渲染         特殊的模板语言                       -- {{ 变量名 }}                           def func(request):                     return render(request, "index.html", {'current_user': "alex"})                                                 index.html                                   <html>                 ..                     <body>                         <div>{{current_user}}</div>                     </body>                                   </html>                                   ====> 最后生成的字符串                                   <html>                 ..                     <body>                         <div>alex</div>                     </body>                                   </html>             -- For循环                 def func(request):                     return render(request, "index.html", {'current_user': "alex", 'user_list': ['alex','eric']})                                                 index.html                                   <html>                 ..                     <body>                         <div>{{current_user}}</div>                                                   <ul>                             {% for row in user_list %}                                                               {% if row == "alex" %}                                     <li>{{ row }}</li>                                 {% endif %}                                                               {% endfor %}                         </ul>                                               </body>                                   </html>                               #####索引#################                 def func(request):                     return render(request, "index.html", {                                 'current_user': "alex",                                 'user_list': ['alex','eric'],                                 'user_dict': {'k1': 'v1', 'k2': 'v2'}})                                                 index.html                                   <html>                 ..                     <body>                         <div>{{current_user}}</div>                                                   <a> {{ user_list.1 }} </a>                         <a> {{ user_dict.k1 }} </a>                         <a> {{ user_dict.k2 }} </a>                                               </body>                                   </html>                           ###### 条件                               def func(request):                     return render(request, "index.html", {                                 'current_user': "alex",                                 "age": 18,                                 'user_list': ['alex','eric'],                                 'user_dict': {'k1': 'v1', 'k2': 'v2'}})                                                 index.html                                   <html>                 ..                     <body>                         <div>{{current_user}}</div>                                                   <a> {{ user_list.1 }} </a>                         <a> {{ user_dict.k1 }} </a>                         <a> {{ user_dict.k2 }} </a>                                                   {% if age %}                             <a>有年龄</a>                             {% if age > 16 %}                                 <a>老男人</a>                             {% else %}                                 <a>小鲜肉</a>                             {% endif %}                         {% else %}                             <a>无年龄</a>                         {% endif %}                     </body>                                   </html>   二、路由系统，URL     1、url(r'^index/', views.index),           url(r'^home/', views.Home.as_view()),     2、url(r'^detail-(\d+).html', views.detail),      3、url(r'^detail-(?P<nid>\d+)-(?P<uid>\d+).html', views.detail)                 PS:             def detail(request, *args,**kwargs):                 pass              实战：             a.                 url(r'^detail-(\d+)-(\d+).html', views.detail),                                   def func(request, nid, uid):                                           pass                               def func(request, *args):                     args = (2,9)                                                             def func(request, *args, **kwargs):                     args = (2,9)                      b.                 url(r'^detail-(?P<nid>\d+)-(?P<uid>\d+).html', views.detail)                                   def func(request, nid, uid):                     pass                                       def funct(request, **kwargs):                     kwargs = {'nid': 1, 'uid': 3}                                       def func(request, *args, **kwargs):                     args = (2,9)     4、 name                   对URL路由关系进行命名， ***** 以后可以根据此名称生成自己想要的URL *****                   url(r'^asdfasdfasdf/', views.index, name='i1'),         url(r'^yug/(\d+)/(\d+)/', views.index, name='i2'),         url(r'^buy/(?P<pid>\d+)/(?P<nid>\d+)/', views.index, name='i3'),                                       def func(request, *args, **kwargs):             from django.urls import reverse                           url1 = reverse('i1')                              # asdfasdfasdf/             url2 = reverse('i2', args=(1,2,))                 # yug/1/2/             url3 = reverse('i3', kwargs={'pid': 1, "nid": 9}) # buy/1/9/                             xxx.html                           {% url "i1" %}               # asdfasdfasdf/             {% url "i2" 1 2 %}           # yug/1/2/             {% url "i3" pid=1 nid=9 %}   # buy/1/9/                   注：             # 当前的URL             request.path_info     5、多级路由                   project/urls.py             from django.conf.urls import url,include             from django.contrib import admin               urlpatterns = [                 url(r'^cmdb/', include("app01.urls")),                 url(r'^monitor/', include("app02.urls")),             ]                       app01/urls.py             from django.conf.urls import url,include             from django.contrib import admin             from app01 import views               urlpatterns = [                 url(r'^login/', views.login),             ]                       app02/urls.py             from django.conf.urls import url,include             from django.contrib import admin             from app02 import views               urlpatterns = [                 url(r'^login/', views.login),             ]           6、默认值（欠）           7、命名空间（欠）             二、视图     1、获取用户请求数据         request.GET         request.POST         request.FILES         PS:             GET:获取数据                            POST:提交数据                   2、checkbox等多选的内容         request.POST.getlist()     3、上传文件         # 上传文件,form标签做特殊设置         obj = request.FILES.get('fafafa')         obj.name         f = open(obj.name, mode='wb')         for item in obj.chunks():             f.write(item)         f.close()           4、FBV & CBV        function base view                  url.py             index -> 函数名                       view.py             def 函数(request):                 ...         ====》         /index/ -> 函数名                       /index/ -> 类                   ====》                   建议：两者都用               5、装饰器         欠         三、模板               四、ORM操作     select * from tb where id > 1     # 对应关系     models.tb.objects.filter(id__gt=1)     models.tb.objects.filter(id=1)     models.tb.objects.filter(id__lt=1)           创建类           a. 先写类         from django.db import models           # app01_userinfo         class UserInfo(models.Model):             # id列，自增，主键             # 用户名列，字符串类型，指定长度             username = models.CharField(max_length=32)             password = models.CharField(max_length=64)               b. 注册APP           INSTALLED_APPS = [             'django.contrib.admin',             'django.contrib.auth',             'django.contrib.contenttypes',             'django.contrib.sessions',             'django.contrib.messages',             'django.contrib.staticfiles',             'app01',         ]     c. 执行命令         python manage.py  makemigrations         python manage.py  migrate               d. ********** 注意 ***********         Django默认使用MySQLdb模块链接MySQL         主动修改为pymysql，在project同名文件夹下的__init__文件中添加如下代码即可：             import pymysql             pymysql.install_as_MySQLdb()           1. 根据类自动创建数据库表         # app下的models.py               python manage.py  makemigrations         python manage.py  migrate                             字段：             字符串类型                                         数字                                         时间                                         二进制                           自增（primary_key=True）                       字段的参数：             null               -> db是否可以为空             default            -> 默认值             primary_key        -> 主键             db_column          -> 列名             db_index           -> 索引             unique               -> 唯一索引             unique_for_date    ->             unique_for_month             unique_for_year             auto_now           -> 创建时，自动生成时间             auto_now_add       -> 更新时，自动更新为当前时间                               # obj = UserGroup.objects.filter(id=1).update(caption='CEO')                 # obj = UserGroup.objects.filter(id=1).first()                 # obj.caption = "CEO"                 # obj.save()                               choices              -> django admin中显示下拉框，避免连表查询             blank             -> django admin是否可以为空             verbose_name      -> django admin显示字段中文             editable          -> django admin是否可以被编辑             error_messages    -> 错误信息欠             help_text         -> django admin提示             validators          -> django form ,自定义错误信息（欠）                                         创建 Django 用户：python manage.py createsuperuser                                                             2. 根据类对数据库表中的数据进行各种操作               一对多：                       a. 外检             b.                 外键字段_id             c.                 models.tb.object.create(name='root', user_group_id=1)                               d.                                   userlist = models.tb.object.all()                 for row in userlist:                     row.id                     row.user_group_id                     row.user_group.caption   1、Django请求的生命周期         路由系统 -> 试图函数(获取模板+数据=》渲染) -> 字符串返回给用户           2、路由系统         /index/                ->  函数或类.as_view()         /detail/(\d+)          ->  函数(参数) 或 类.as_view()（参数）         /detail/(?P<nid>\d+)   ->  函数(参数) 或 类.as_view()（参数）         /detail/               ->  include("app01.urls")         /detail/    name='a1'  ->  include("app01.urls")                                - 视图中：reverse                                - 模板中：{% url "a1" %}                                  3、视图     FBV：函数         def index(request,*args,**kwargs):             ..           CBV：类         class Home(views.View):                           def get(self,reqeust,*args,**kwargs):                 ..                       获取用户请求中的数据：         request.POST.get         request.GET.get         reqeust.FILES.get()                   # checkbox,         ........getlist()                   request.path_info                             文件对象 = reqeust.FILES.get()         文件对象.name         文件对象.size         文件对象.chunks()                   # <form 特殊的设置></form>                         给用户返回数据：         render(request, "模板的文件的路径", {'k1': [1,2,3,4],"k2": {'name': '张扬','age': 73}})         redirect("URL")         HttpResponse(字符串)                 4、模板语言         render(request, "模板的文件的路径", {'obj': 1234, 'k1': [1,2,3,4],"k2": {'name': '张扬','age': 73}})           <html>           <body>         <h1> {{ obj }} </h1>         <h1> {{ k1.3 }} </h1>         <h1> {{ k2.name }} </h1>         {% for i in k1 %}             <p> {{ i }} </p>         {% endfor %}                   {% for row in k2.keys %}             {{ row }}         {% endfor %}                   {% for row in k2.values %}             {{ row }}         {% endfor %}                   {% for k,v in k2.items %}             {{ k }} - {{v}}         {% endfor %}               </body>     </html>       5、ORM     a. 创建类和字段         class User(models.Model):             age = models.IntergerFiled()             name = models.CharField(max_length=10)#字符长度                       Python manage.py makemigrations         python manage.py migrate                   # settings.py 注册APP               b. 操作                   增             models.User.objects.create(name='qianxiaohu',age=18)             dic = {'name': 'xx', 'age': 19}             models.User.objects.create(**dic)                                         obj = models.User(name='qianxiaohu',age=18)             obj.save()         删             models.User.objects.filter(id=1).delete()         改             models.User.objects.filter(id__gt=1).update(name='alex',age=84)             dic = {'name': 'xx', 'age': 19}             models.User.objects.filter(id__gt=1).update(**dic)         查             models.User.objects.filter(id=1,name='root')             models.User.objects.filter(id__gt=1,name='root')             models.User.objects.filter(id__lt=1)             models.User.objects.filter(id__gte=1)             models.User.objects.filter(id__lte=1)                           models.User.objects.filter(id=1,name='root')             dic = {'name': 'xx', 'age__gt': 19}             models.User.objects.filter(**dic)                           v1 = models.Business.objects.all()             # QuerySet ,内部元素都是对象                           # QuerySet ,内部元素都是字典             v2 = models.Business.objects.all().values('id','caption')             # QuerySet ,内部元素都是元组             v3 = models.Business.objects.all().values_list('id','caption')                       # 获取到的一个对象，如果不存在就报错             models.Business.objects.get(id=1)             对象或者None = models.Business.objects.filter(id=1).first()                                         外键：                 v = models.Host.objects.filter(nid__gt=0)                 v[0].b.caption  ---->  通过.进行跨表           外键：             class UserType(models.Model):                 caption = models.CharField(max_length=32)               id  caption             # 1，普通用户             # 2，VIP用户             # 3， 游客                               class User(models.Model):                 age = models.IntergerFiled()                 name = models.CharField(max_length=10)#字符长度                 # user_type_id = models.IntergerFiled() # 约束，                 user_type = models.ForeignKey("UserType",to_field='id') # 约束，                         name age  user_type_id                 # 张扬  18     3             # 张A扬 18     2             # 张B扬 18     2           position:fixed absolute relative             Ajax               $.ajax({             url: '/host',             type: "POST",             data: {'k1': 123,'k2': "root"},             success: function(data){                 // data是服务器端返回的字符串                 var obj = JSON.parse(data);             }         })               建议：永远让服务器端返回一个字典                   return HttpResponse(json.dumps(字典))                        多对多：     创建多对多：         方式一：自定义关系表             class Host(models.Model):                 nid = models.AutoField(primary_key=True)                 hostname = models.CharField(max_length=32,db_index=True)                 ip = models.GenericIPAddressField(protocol="ipv4",db_index=True)                 port = models.IntegerField()                 b = models.ForeignKey(to="Business", to_field='id')             # 10             class Application(models.Model):                 name = models.CharField(max_length=32)             # 2                           class HostToApp(models.Model):                 hobj = models.ForeignKey(to='Host',to_field='nid')                 aobj = models.ForeignKey(to='Application',to_field='id')                               # HostToApp.objects.create(hobj_id=1,aobj_id=2)                           方式二：自动创建关系表             class Host(models.Model):                 nid = models.AutoField(primary_key=True)                 hostname = models.CharField(max_length=32,db_index=True)                 ip = models.GenericIPAddressField(protocol="ipv4",db_index=True)                 port = models.IntegerField()                 b = models.ForeignKey(to="Business", to_field='id')             # 10             class Application(models.Model):                 name = models.CharField(max_length=32)                 r = models.ManyToManyField("Host")                               无法直接对第三张表进行操作                           obj = Application.objects.get(id=1)             obj.name                           # 第三张表操作             obj.r.add(1)             obj.r.add(2)             obj.r.add(2,3,4)             obj.r.add(*[1,2,3,4])                           obj.r.remove(1)             obj.r.remove(2,4)             obj.r.remove(*[1,2,3])                           obj.r.clear()                           obj.r.set([3,5,7])                           # 所有相关的主机对象“列表” QuerySet             obj.r.all()