django框架的使用及其梳理系列二

路由源码流程

#urls.py中ctrl+鼠标点击
path = partial(_path, Pattern=RoutePattern)

#partial的功能:
from functools import partial

def _path(v1, v2, v3):
    return v1 + v2 + v3

path = partial(_path, v3=55)
print(path(11, 22))

_path:

def _path(route, view, kwargs=None, name=None, Pattern=None):
    if isinstance(view, (list, tuple)):
        # For include(...) processing.
        pattern = Pattern(route, is_endpoint=False)
        #
        return URLResolver(
            pattern,
            urlconf_module,
            kwargs,
            app_name=app_name,
            namespace=namespace,
        )

#本质
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),
]

urlpattern和routepattern:

class URLPattern:
    def __init__(self, pattern, callback, default_args=None, name=None):
        self.pattern = pattern
        self.callback = callback  # the view
        self.default_args = default_args or {}
        self.name = name
        
class RoutePattern(CheckURLMixin):
    regex = LocaleRegexDescriptor('_route')

    def __init__(self, route, name=None, is_endpoint=False):
        self._route = route
        self._regex_dict = {}
        self._is_endpoint = is_endpoint
        self.name = name
        self.converters = _route_to_regex(str(route), is_endpoint)[1]

项目启动：

wsgi.py

#call方法就是程序的入口
class WSGIHandler(base.BaseHandler):
    request_class = WSGIRequest

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.load_middleware()

    def __call__(self, environ, start_response):
        set_script_prefix(get_script_name(environ))
        signals.request_started.send(sender=self.__class__, environ=environ)
        request = self.request_class(environ)
        response = self.get_response(request)

        response._handler_class = self.__class__

看到：

response = self.get_response(request)

再进get_response, middleware_chain:

进入handler：

跳过异步的函数,看

 callback, callback_args, callback_kwargs = self.resolve_request(request)
    
匹配成功：
 # Resolve the view, and assign the match object back to the request.
        resolver_match = resolver.resolve(request.path_info)
        request.resolver_match = resolver_match
        return resolver_match

1.resolver = get_resolver(), 即return URLResolver(RegexPattern(r'^/'), urlconf)
2.resolver.resolve路由匹配
3.request.resolver_match = 返回的resolver_match

进入resolve_request:

name别名：

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

from django.urls import reverse

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

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/"

意义：

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

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")