路由系统

1 常见操作

通俗的语言来表示：URL -> 函数对应关系

2 路由源码分析

2.1 路由定义的本质

from django.urls import path, re_path
from apps.www import views

from django.urls import URLPattern
from django.urls.resolvers import RoutePattern

urlpatterns = [

    URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
    path('login/', views.login, name='n1'),

    # http://127.0.0.1:8000/info/2222/
    # http://127.0.0.1:8000/info/2222/?a1=1&b1=2
    # path('info/<int:v1>/', views.info),

    # http://127.0.0.1:8000/other/11/wupeiqi/
    # http://127.0.0.1:8000/other/222/alex/
    # path('other/<int:v1>/<str:v2>/', views.other),

    # path('xx/<path:v2>/', views.xx),
    # path('xx/<uuid:v2>/', views.xx),

    # http://127.0.0.1:8000/yy/2014-11-11
    # re_path(r'yy/(\d{4})-(\d{2})-(\d{2})/', views.yy),
]

• 编写路由

• 启动项目时

  urlpatterns = [
  	对象(URL地址、函数）,
  	对象(URL地址、函数）,
  	对象,
  	对象,
  	对象，
  	URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
  ]
  
  # 内部路由匹配的时，默认执行：
  URLPattern.resolve
      self.pattern.match()
      return ResolverMatch(...)
      
  # 进阶操作
  # 路由系统中的扩展点：
  	URLPattern.resolve
  	RoutePattern.match
  	自定义ResolverMatch类
  

• 用户浏览器访问

  http://127.0.0.1:8000/login/
  

• django的源码内部，一定会匹配，获得相应的视图函数

  http://127.0.0.1:8000 /login/
  
  urlpatterns = [
  	对象(URL地址、函数）,
  	对象(URL地址、函数）,
  	对象,
  	对象,
  	对象
  ]
  

  urlconf = 'day006.urls'
  resolver = URLResolver(RegexPattern(r"^/"), urlconf)
  
  resolver_match = resolver.resolve(request.path_info)
  
  callback, callback_args, callback_kwargs = resolver_match
  

• 执行视图函数

  urlpatterns = [
      path('login/', views.login),
      path('info/<int:v1>/', views.info),
  ]
  

  urlpatterns = [
      URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
      URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
      URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
      URLPattern(RoutePattern("login/", name=None, is_endpoint=True), views.login, None, None),
  ]
  

• 源码内部路由匹配的时，是怎么做的？

  URLPattern.resolve
  	RoutePattern.match
  

  def resolve(self, path):
      match = self.pattern.match(path)
      if match:
          new_path, args, captured_kwargs = match
          # Pass any default args as **kwargs.
          kwargs = {**captured_kwargs, **self.default_args}
          return ResolverMatch(
              self.callback,
              args,
              kwargs,
              self.pattern.name,
              route=str(self.pattern),
              captured_kwargs=captured_kwargs,
              extra_kwargs=self.default_args,
          )
  
  

  
      def match(self, path):
          match = self.regex.search(path)
          if match:
              # RoutePattern doesn't allow non-named groups so args are ignored.
              kwargs = match.groupdict()
              for key, value in kwargs.items():
                  converter = self.converters[key]
                  try:
                      kwargs[key] = converter.to_python(value)
                  except ValueError:
                      return None
              return path[match.end() :], (), kwargs
          return None
  
  

2.3 name别名

path('login/', views.login, name='n1'),
URLPattern(RoutePattern("login/", name="n1", is_endpoint=True), views.login, None, "n1"),

def login(request):
    return HttpResponse("欢迎登陆")

from django.urls import reverse

result = reverse("n1")
print(result) # "login/"

path('api/auth/login/<int:v1>/', views.login, name='n1'),

def login(request,v1):
    return HttpResponse("欢迎登陆")

from django.urls import reverse

result = reverse("n1",kwargs={"v1":123})
print(result) # "/api/auth/login/123/"

result = reverse("n1",kwargs={"v1":999})
print(result) # "/api/auth/login/999/"

name存在的意义？例如：用户登录登录程序

/api/auth/login/         ->   函数登录
/api/user/account/      ->    函数账单

path('api/auth/login/',  views.login,  name='n1'),
path('api/user/account/', views.account, name='n2'),

def login(request):
    # 当用户登录成功之后，需要让用户跳转到 /api/user/account/ 页面
    # return redirect("/api/user/account/")
    
	# url = reverse("n2")   # "/api/user/account/"
    # return redirect(url)

	return redirect("n2")
    
def account(request):
    return HttpResponse("用户信息")

name存在的意义？例如：权限管理

A用户有权访问的网址：
	/api/auth/login/ 
	/api/user/account/
	/api/user/order/
	/api/user/order/<int:v1>/
	
B用户有权访问的网址：
	/api/user/account/
	/api/user/order/
	/api/user/order/<int:v1>/

A用户有权访问的网址：
	n1
	n2
	n3
	
B用户有权访问的网址：
	n2
	n3