Django- 反向生成url

Django中提供了一个关于URL的映射的解决方案，

1.客户端的浏览器发起一个url请求，Django根据URL解析，把url中的参数捕获，调用相应的试图，获取相应的数据，然后返回给客户端显示

2.通过一个视图的名字，再加上一些参数和值，逆向获取相应的URL

第一个就是平常的请求有URLconf来解析的过程，

第二个叫做，url的逆向解析，url逆向匹配，url的逆向查阅，等

Django提供了不同的层级的url逆向处理工具：

1.在模板templates中，使用url标记，如：{% url %}

2.在Python代码中，使用django.core.urlresolvers.reverse()方法

3.在更高一层级的处理url中，用get_absolute_url()方法

新一个项目diango

访问longin页面跳转到 index页面

app01 views.py 

from django.shortcuts import render,redirect,HttpResponse

def index(request):
    return HttpResponse('Index')

def login(request):
    return HttpResponse('longin')

urls.py 

from django.conf.urls import url
from app01 import views

urlpatterns = [
    url(r'^index/', views.index),
    url(r'^login/', views.login),

]

在平常做法

views.py

def login(request):
    return redirect('/index/')

如果usr 很长 
urlpatterns = [
    url(r'^index/xxxxx/xxx/xxx/xxx/xx/', views.index),
    url(r'^login/', views.login),
]

可以用平常做法：

 app01 views.py

def login(request):
    return redirect('/index/xxxxx/xxx/xxx/xxx/xx/')

这种方法看上去不是那么的友好, 我们用usl 别名的方式

 导入reverse 

app01/views.py

from django.urls import reverse
def login(request):
    url = ('inx')
    return redirect(url)

urls.py

urlpatterns = [
    url(r'^index/xxxxx/xxx/xxx/xxx/xx/', views.index,name='inx'),
]

通过 usl名称，反向生成usl 

include方法来实现路由转发功能

urls.py

url(r'^cmdb/', include’(crm.urls)’),

 crm/urls.py 

from django.conf.urls import url,include
from django.contrib import admin
from crm import views
urlpatterns = [
    url(r'^hosts/', views.hosts,name='hosts'),
]

crm/views.py

def hosts(request):
   return HttpResponse('主机列表')

通过这个cmdb前缀分发，分发到自己的urls中，好处可以将各种的业务拆分

反向生成时，使用reverse(‘namespace:name’)

 新建app,  monitor 、openstack , 

url(r'^monitor/', include('monitor.urls',namespace='m')),
url(r'^openstack/', include('openstack.urls',namespace='o')),

monitor/ulrs.py

from django.conf.urls import url,include
from django.contrib import admin
from monitor import views
urlpatterns = [
    url(r'^hosts/', views.hosts,name='hosts'),
]

monitor/views.py

from django.shortcuts import render,HttpResponse
def hosts(request):
    return HttpResponse('监控系统，主机列表')

openstack /ulrs.py

from django.conf.urls import url,include
from django.contrib import admin
from openstack import views
urlpatterns = [
    url(r'^hosts/', views.hosts,name='hosts'),
]

openstack /views.py

from django.shortcuts import render,HttpResponse

def hosts(request):
    return HttpResponse('OpenStack，主机列表')

登录成功时跳转到 openstack/主机列表页面

def login(request):
    return HttpResponse('Login')
    # 跳转到 openstack主机列表页面
    # return redirect('/openstack/hosts/')
    url = reverse('o:hosts')

include本质 【就是元组，一级一级做分发】

 urls.py

from monitor import views as mviews
from openstack import views as oviews
    # /monitor/hosts/
    url(r'^login/', views.login),
        url(r'^monitor/', ([
                                url(r'^hosts/',mviews.hosts,name='hhhhh'),
                                url(r'^c1/',mviews.hosts),
                                url(r'^x1/', ([
                                                url(r'^xxx1/',mviews.hosts),
                                                url(r'^xxx2/',mviews.hosts,name='xx2'),
                                                url(r'^xxx3/',mviews.hosts),
                                                url(r'^xxx4/',mviews.hosts),
                                            ],None,None)),
                                url(r'^c2/',mviews.hosts),
                                url(r'^c3/',mviews.hosts),
                            ],None,'mm')),
        url(r'^openstack/', ([
                                url(r'^hosts/',oviews.hosts,name='hhhhh'),
                                url(r'^c1/',oviews.hosts),
                                url(r'^c2/',oviews.hosts),
                                url(r'^c3/',oviews.hosts),
                            ],None,'oo')),
]

views.py

    # 跳转到 openstack主机列表页面
     url = reverse('oo:hhhhh')
     url = reverse('mm:uu:xx2')

动态生成url

views.py

def login(request):
    return HttpResponse('Login')

urls.py

urlpatterns = [
    url(r'^login/', views.login),
]

for i in range(10):
    temp = []
    for j in range(5):
        temp.append(url(r'^inner_%s/' % j, views.login))
    v = url(r'^login_%s/' %i, (temp,None,None))
    urlpatterns.append(v)