[Python知识库]【Django框架】——23 Django视图 05 HttpResponse对象

HttpRequest对象由Django创建，HttpResponse对象由开发?员创建。

class HttpResponse(HttpResponseBase):
    """
    An HTTP response class with a string as content.

    This content that can be read, appended to, or replaced.
    """

    streaming = False

    def __init__(self, content=b'', *args, **kwargs):
        super().__init__(*args, **kwargs)
        # Content is a bytestring. See the `content` property methods.
        self.content = content

    def __repr__(self):
        return '<%(cls)s status_code=%(status_code)d%(content_type)s>' % {
            'cls': self.__class__.__name__,
            'status_code': self.status_code,
            'content_type': self._content_type_for_repr,
        }

    def serialize(self):
        """Full HTTP message, including headers, as a bytestring."""
        return self.serialize_headers() + b'\r\n\r\n' + self.content

    __bytes__ = serialize

    @property
    def content(self):
        return b''.join(self._container)

    @content.setter
    def content(self, value):
        # Consume iterators upon assignment to allow repeated iteration.
        if hasattr(value, '__iter__') and not isinstance(value, (bytes, str)):
            content = b''.join(self.make_bytes(chunk) for chunk in value)
            if hasattr(value, 'close'):
                try:
                    value.close()
                except Exception:
                    pass
        else:
            content = self.make_bytes(value)
        # Create a list of properly encoded bytestrings to support write().
        self._container = [content]

    def __iter__(self):
        return iter(self._container)

    def write(self, content):
        self._container.append(self.make_bytes(content))

    def tell(self):
        return len(self.content)

    def getvalue(self):
        return self.content

    def writable(self):
        return True

    def writelines(self, lines):
        for line in lines:
            self.write(line)

1. HttpResponse

可以使?django.http.HttpResponse来构造响应对象。

HttpResponse(content=响应体, content_type=响应体数据类型, status=状态码)

也可通过HttpResponse对象属性来设置响应体、响应体数据类型、状态码：

• content：表示返回的内容。

• status_code：返回的HTTP响应状态码。 响应头可以直接将HttpResponse对象当做字典进?响应头键值对的设置：

response = HttpResponse('bei ji de san ha !')
response['bei ji de san ha !'] = 'Python'

# ?定义响应头bei ji de san ha, 值为Python

示例：

from django.shortcuts import render
from django.http import HttpResponse

# Create your views here.


def response(request):
    return HttpResponse(content='Hello HttpResponse', content_type=str, status=400)

或者：

from django.shortcuts import render
from django.http import HttpResponse

# Create your views here.


def response(request):
    # return HttpResponse(content='Hello HttpResponse', content_type=str, status=400)
    response = HttpResponse('bei ji de san ha !')
    response.status_code = 400
    response['bei ji de san ha !'] = 'Python'
    return respons

2. HttpResponse?类

Django提供了?系列HttpResponse的?类，可以快速设置状态码。

HttpResponseRedirect 301
HttpResponsePermanentRedirect 302
HttpResponseNotModified 304
HttpResponseBadRequest 400
HttpResponseNotFound 404
HttpResponseForbidden 403
HttpResponseNotAllowed 405
HttpResponseGone 410
HttpResponseServerError 500

示例：HttpResponseRedirect 301

视图函数：

from django.shortcuts import render
from django.http import HttpResponse, HttpResponseRedirect

# Create your views here.


def response(request):
    return HttpResponseRedirect('/hrv/')


def httpResponseView(request):
    return HttpResponse('Hello Django HttpResponse')

路由：

# -*- coding: utf-8 -*-
# @File  : urls.py
# @author: 北极的三哈
# @email : Flymeawei@163.com
# @Time  : 2022/10/31 上午2:35
""""""
from django.urls import path, re_path
from papp import views


urlpatterns = [
    path('response/', views.response),
    path('hrv/', views.httpResponseView),
]

访问：127.0.0.1:8000/response/

响应：http://127.0.0.1:8000/hrv/

3. JsonResponse

class JsonResponse(HttpResponse):
    """
    An HTTP response class that consumes data to be serialized to JSON.

    :param data: Data to be dumped into json. By default only ``dict`` objects
      are allowed to be passed due to a security flaw before EcmaScript 5. See
      the ``safe`` parameter for more information.
    :param encoder: Should be a json encoder class. Defaults to
      ``django.core.serializers.json.DjangoJSONEncoder``.
    :param safe: Controls if only ``dict`` objects may be serialized. Defaults
      to ``True``.
    :param json_dumps_params: A dictionary of kwargs passed to json.dumps().
    """

    def __init__(self, data, encoder=DjangoJSONEncoder, safe=True,
                 json_dumps_params=None, **kwargs):
        if safe and not isinstance(data, dict):
            raise TypeError(
                'In order to allow non-dict objects to be serialized set the '
                'safe parameter to False.'
            )
        if json_dumps_params is None:
            json_dumps_params = {}
        kwargs.setdefault('content_type', 'application/json')
        data = json.dumps(data, cls=encoder, **json_dumps_params)
        super().__init__(content=data, **kwargs)

若要返回json数据，可以使?JsonResponse来构造响应对象，作?：

• 帮助我们将数据转换为json字符串

• 设置响应头Content-Type为application/json

from django.shortcuts import render
from django.http import HttpResponse, JsonResponse

# Create your views here.


def response(request):
    # return HttpResponse(content='Hello HttpResponse', content_type=str, status=400)

    # response = HttpResponse('bei ji de san ha !')
    # response.status_code = 400
    # response['bei ji de san ha !'] = 'Python'
    # return response

    return JsonResponse({'uname': 'san ha', 'age': 22})

访问：http://127.0.0.1:8000/response/

JSON

原始数据

头

4. redirect重定向

def redirect(to, *args, permanent=False, **kwargs):
    """
    Return an HttpResponseRedirect to the appropriate URL for the arguments
    passed.

    The arguments could be:

        * A model: the model's `get_absolute_url()` function will be called.

        * A view name, possibly with arguments: `urls.reverse()` will be used
          to reverse-resolve the name.

        * A URL, which will be used as-is for the redirect location.

    Issues a temporary redirect by default; pass permanent=True to issue a
    permanent redirect.
    """
    redirect_class = HttpResponsePermanentRedirect if permanent else HttpResponseRedirect
    return redirect_class(resolve_url(to, *args, **kwargs))

视图函数：

from django.shortcuts import render
from django.http import HttpResponse, JsonResponse, HttpResponseRedirect
from django.shortcuts import redirect

# Create your views here.


def response(request):
    # return HttpResponse(content='Hello HttpResponse', content_type=str, status=400)

    # response = HttpResponse('bei ji de san ha !')
    # response.status_code = 400
    # response['bei ji de san ha !'] = 'Python'
    # return response

    # return JsonResponse({'uname': 'san ha', 'age': 22})

    # return HttpResponseRedirect('/hrv/')
    
    return redirect('/hrv/')


def httpResponseView(request):
    return HttpResponse('Hello Django HttpResponse')

路由：

# -*- coding: utf-8 -*-
# @File  : urls.py
# @author: 北极的三哈
# @email : Flymeawei@163.com
# @Time  : 2022/10/31 上午2:35
""""""
from django.urls import path, re_path
from papp import views


urlpatterns = [
    path('response/', views.response),
    path('hrv/', views.httpResponseView),
]

访问：127.0.0.1:8000/response/

响应：http://127.0.0.1:8000/hrv/