標籤:業務 inf http請求 ike ISE __name__ 方式 roc 基本
Django請求的生命週期是指:當使用者在訪問該url路徑是,在伺服器Django後台都發生了什麼。
用戶端發送Http請求給服務端,Http請求是一堆字串,其內容是:
訪問:http://crm.oldboy.com:8080/login.html,用戶端發送Http請求
1.路由映射,匹配路由(從上到下,匹配到就停止),對應相應views中的業務函數
url(r‘^login.html‘, views.login),
2.匹配成功後,執行views下的對應函數:(FBV)
def login(req): print(‘req.body‘,req.body) print("GET",req.GET) message=‘‘ if req.method == "POST": print(req.body) print(req.POST) user = req.POST.get("username") pwd = req.POST.get("password") count = models.Administrator.objects.filter(username=user,password=pwd).count() if count: red = redirect("/index.html") timeout = datetime.datetime.now()+datetime.timedelta(seconds=3) red.set_cookie(‘username‘,user,expires=timeout) return red else: message = "使用者名稱或密碼錯誤" return render(req,"login.html",{‘msg‘:message})View Code
URL --> 函數 ====> FBV(Function-based views) 基於函數的視圖
URL --> 類 ====> CBV (Class-based views) 基於類的視圖
FBV:在Django中使用較多,在其他架構中多使用CBV,例如tornado,還有PHP的多種架構等
Django中CBV使用:
首先需要設定views中的類:
from django.views import Viewclass CBV(View):
#根據要求標頭中的request method進行自動執行get和post def get(self,request): return render(request,"cbv_login.html") def post(self,request): return HttpResponse("<h1>cbv_post</h1>")
然後修改urls檔案路由:
urlpatterns = [ url(r"cbv",views.CBV.as_view())]
模板檔案:
<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title></head><body><form action="/cbv" method="post"> {% csrf_token %} <div> <label for="user">使用者名稱:</label> <input type="text" id="user" name="username"/> </div> <div> <label for="pwd">密碼:</label> <input type="password" id="pwd" name="password"/> </div> <div> <label></label> <input type="submit" value="登入"> <label>{{ msg }}</label> </div></form></body></html>cbv_login.html
使用url訪問預設是get方式,顯示cbv_login.html頁面,提交頁面,進入post頁面,顯示cbv_post資料
get還是post,是由於要求標頭中的Request Method:擷取,從而找到對應方法。使用反射尋找,來執行對應方法。
1.由Request URL請求去擷取路徑,與urls進行匹配,找到對應的類2.由請求體得到:Request Method:GET3.獲得類中方法 方法名 = getattr(對象,"GET") 方法名() #執行對應函數
源碼查看:
@classonlymethod def as_view(cls, **initkwargs): """ Main entry point for a request-response process.要求-回應的主進入點,在url解析時調用 """ for key in initkwargs: #cls.http_method_names: #[u‘get‘, u‘post‘, u‘put‘, u‘patch‘, u‘delete‘, u‘head‘, u‘options‘, u‘trace‘] if key in cls.http_method_names: raise TypeError("You tried to pass in the %s method name as a " "keyword argument to %s(). Don‘t do that." % (key, cls.__name__)) if not hasattr(cls, key): raise TypeError("%s() received an invalid keyword %r. as_view " "only accepts arguments that are already " "attributes of the class." % (cls.__name__, key)) #print(cls) #<class ‘app1.views.CBV‘> def view(request, *args, **kwargs): self = cls(**initkwargs) #執行個體化CBV對象 if hasattr(self, ‘get‘) and not hasattr(self, ‘head‘): self.head = self.get self.request = request #print(request) <WSGIRequest: GET ‘/cbv‘> #print(request.method) GET self.args = args self.kwargs = kwargs return self.dispatch(request, *args, **kwargs)#調用dispatch方法,將<WSGIRequest: GET ‘/cbv‘>傳入 view.view_class = cls view.view_initkwargs = initkwargs # take name and docstring from class update_wrapper(view, cls, updated=()) # and possible attributes set by decorators # like csrf_exempt from dispatch update_wrapper(view, cls.dispatch, assigned=()) return view def dispatch(self, request, *args, **kwargs): # Try to dispatch to the right method; if a method doesn‘t exist, # defer to the error handler. Also defer to the error handler if the # request method isn‘t on the approved list. if request.method.lower() in self.http_method_names: handler = getattr(self, request.method.lower(), self.http_method_not_allowed) #去調用對應的函數 else: handler = self.http_method_not_allowed return handler(request, *args, **kwargs)
推薦:介紹——基於類的視圖(class-based view)
3.業務處理
-----根據個人需求自訂
-----對於架構:基本操作是操作資料庫
---pymysql (原生)
---SQLAlchemy
---Django中orm
-----響應內容:返回給使用者的結果:回應標頭和響應體
我們寫的HTTPResponse是寫在響應體中
回應標頭的定製:
def post(self,request): ret = HttpResponse("<h1>post</h1>")
#下面為佈建要求頭 ret[‘h1‘] =‘v1‘ ret.set_cookie(‘c1‘,‘v1‘) ret.set_cookie(‘c2‘,‘v2‘) ‘‘‘ 回應標頭:h1=v1 cookies:c1=v1;c2=v2 響應體:<h1>post</h1> 要求標頭資訊: Content-Length:13 Content-Type:text/html; charset=utf-8 Date:Wed, 28 Mar 2018 13:54:53 GMT h1:v1 Server:WSGIServer/0.1 Python/2.7.10 Set-Cookie:c2=v2; Path=/ Set-Cookie:c1=v1; Path=/ X-Frame-Options:SAMEORIGIN ‘‘‘ return ret
python---django要求-回應的生命週期(FBV和CBV含義)