How does Django determine the source of the request?

Django can determine the source of a request by using the attributes of the request object. Here are some commonly used attributes:

1. The request.META.get(‘HTTP_REFERER’) method returns a string containing the source page where the user clicked the link to access the current page. If the user directly visits the current page or enters it through bookmarks, browser history, etc., the value of this property will be an empty string.
2. request.get_host(): returns a string containing the hostname of the current request. For example, if the user is accessing http://example.com/mypage, the value of this attribute will be example.com.
3. request.META.get(‘REMOTE_ADDR’): returns the user’s IP address.
4. request.META.get(‘HTTP_USER_AGENT’): Returns a string containing the user’s browser agent.

Based on the values of these attributes, you can determine the source of access, such as:

def my_view(request):
    referer = request.META.get('HTTP_REFERER')
    host = request.get_host()
    remote_addr = request.META.get('REMOTE_ADDR')
    user_agent = request.META.get('HTTP_USER_AGENT')

    # 判断是否为直接访问
    if referer == '':
        # 处理直接访问的情况
        pass

    # 判断是否为外部链接
    if 'example.com' not in referer and host != 'example.com':
        # 处理外部链接的情况
        pass

    # 判断是否为特定IP地址
    if remote_addr == '127.0.0.1':
        # 处理特定IP地址的情况
        pass

    # 判断用户的浏览器类型
    if 'Mozilla' in user_agent:
        # 处理Mozilla浏览器的情况
        pass

    # 其他判断逻辑...

Please note that request.META is a dictionary containing all the metadata for the HTTP request. You can refer to the Django official documentation for more information on the request object and the META attribute.