跨域（my）

CORS跨域请求

CORS即Cross Origin Resource Sharing 跨域资源共享，

那么跨域请求还分为两种，一种叫简单请求，一种是复杂请求~~

简单请求

HTTP方法是下列方法之一

　　HEAD， GET，POST

HTTP头信息不超出以下几种字段

　　Accept， Accept-Language， Content-Language， Last-Event-ID

　　Content-Type只能是下列类型中的一个

　　　　application/x-www-from-urlencoded

　　　　multipart/form-data

　　　　text/plain

任何一个不满足上述要求的请求，即会被认为是复杂请求~~

复杂请求会先发出一个预请求，我们也叫预检，OPTIONS请求~~

浏览器的同源策略

跨域是因为浏览器的同源策略导致的，也就是说浏览器会阻止非同源的请求~

那什么是非同源呢~~即域名不同，端口不同都属于非同源的~~~

浏览器只阻止表单以及ajax请求，并不会阻止src请求，所以我们的cnd，图片等src请求都可以发~~

Ajax跨域现象

urls.py:

 

from django.conf.urls import url
from django.contrib import admin
from .views import jsonp1

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^jsonp1',jsonp1)
]
View Code

 

views.py

from django.http import HttpResponse

def jsonp1(request):
    return HttpResponse("hello")
View Code

创建 .html 当做前端：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.js"></script>
<body>
<button id="btn">点我向后端发送数据</button>
<script>

    $("#btn").click(function(){
        $.ajax({
            url:"http://127.0.0.1:8000/jsonP1" ,  //后端的路由地址

            success:function(data){
                console.log(data)
            }
        })

                            })
</script>
</body>
</html>
jsonp2

 

 

解决跨域

JSONP

jsonp的实现原理是根据浏览器不阻止src请求入手~来实现的~~

urls.py:

from django.conf.urls import url
from django.contrib import admin
from .views import jsonp1

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^jsonp1',jsonp1)
]
View Code

views.py:

from django.http import HttpResponse

def jsonp1(request):

    ret = "handlerResponse('hello555')"
    return HttpResponse(ret)
View Code

jsonp2.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.js"></script>
<body>
<button id="btn">点我向后端发送数据</button>
<script>



   // 页面加载完成执行的方法
    window.onload = function () {
        let ele = document.createElement("script");
        // 给标签加src属性
        ele.src = "http://127.0.0.1:8001/jsonp1";
        // 把标签放到页面上
         document.body.insertBefore(ele, null)
    }

    function handlerResponse(data) {
        alert(data)
    }
</script>
</body>
</html>
View Code

===========================

views.py:

from django.http import HttpResponse

def jsonp1(request):
    callback = request.GET.get("callback","")#获取callback

    # ret = "handlerResponse('hello555')"
    ret = callback + "('hello')"
    return HttpResponse(ret)
View Code

jsonp2.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.js"></script>
<body>
<button id="btn">点我向后端发送数据</button>
<script>


    function handlerResponse(data) {
        alert(data)
    }
   // 页面加载完成执行的方法
    window.onload = function () {
        let ele = document.createElement("script");
        // 给标签加src属性
        ele.src = "http://127.0.0.1:8001/jsonp1?callback=handlerResponse";
        // 把标签放到页面上
         document.body.insertBefore(ele, null)
    }


</script>
</body>
</html>
View Code

添加响应头

settings.py注释中间件csrf

注册中间件：'middlewares.MyCors'

 urls.py:

from django.conf.urls import url
from django.contrib import admin
from .views import jsonp1

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^jsonp1',jsonp1)
]
View Code

 

jsonp2.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.js"></script>
<body>
<button id="btn">点我向后端发送数据</button>
<script>



    $("#btn").click(function () {
        $.ajax({
            url: "http://127.0.0.1:8001/jsonp1",
            type: "post",
            contentType: "application/json",
            data: {"name": "liangshuang"},
            success: function (data) {
                console.log(data)
            }
        })
    })








</script>
</body>
</html>
View Code

views.py

from django.http import HttpResponse

def jsonp1(request):
    callback = request.GET.get("callback","")#获取callback

    # ret = "handlerResponse('hello555')"
    ret = callback + "('hello')"
    print(ret)
    return HttpResponse(ret)
View Code

在项目下创建middlewares.py定义中间件

# -*- coding: utf-8 -*-
# __author__ = "maple"
from django.middleware.security import SecurityMiddleware
from django.utils.deprecation import MiddlewareMixin


class MyCors(MiddlewareMixin):
    def process_response(self, request, response):
        # 简单请求
        response["Access-Control-Allow-Origin"] = "*"
        # 复杂请求 会先发送预检请求 OPTIONS
        if request.method == "OPTIONS":
            response["Access-Control-Allow-Headers"] = "Content-Type"
            response["Access-Control-Allow-Methods"] = "POST, PUT, PATCH, DELETE"
        return response
View Code

 

posted on 2018-11-02 21:56  liangliang123456  阅读(131)  评论(0)  编辑  收藏  举报

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