Django REST framework 源码剖析-渲染器图解(Renderers)

Django REST framework 源码剖析-渲染器图解(Renderers)

  • 在Django REST framework (DRF) 中,渲染器(Renderers)组件承担着将后端响应数据转换为客户端可解析的格式的职责。它们是数据序列化的关键部分,确保服务器以客户端所能理解的方式返回数据。渲染器会根据客户端请求中的 Accept头来选择适当的格式, 将响应数据转换为JSON、XML、HTML等不同格式, 以适应不同类型的客户端需求。

视图调用源码

  • rest_framework.views
python 复制代码
class APIView(View):

    # The following policies may be set at either globally, or per-view.
    renderer_classes = api_settings.DEFAULT_RENDERER_CLASSES

JSONRenderer源码

  • rest_framework.renderers
python 复制代码
class JSONRenderer(BaseRenderer):
    """
    Renderer which serializes to JSON.
    """
    media_type = 'application/json'
    format = 'json'
    charset = None

TemplateHTMLRenderer源码

  • rest_framework.renderers
python 复制代码
class TemplateHTMLRenderer(BaseRenderer):
    """
    An HTML renderer for use with templates.

    The data supplied to the Response object should be a dictionary that will
    be used as context for the template.

    The template name is determined by (in order of preference):

    1. An explicit `.template_name` attribute set on the response.
    2. An explicit `.template_name` attribute set on this class.
    3. The return result of calling `view.get_template_names()`.

    For example:
        data = {'users': User.objects.all()}
        return Response(data, template_name='users.html')

    For pre-rendered HTML, see StaticHTMLRenderer.
    """
    media_type = 'text/html'
    format = 'html'
    charset = 'utf-8'

StaticHTMLRenderer源码

  • rest_framework.renderers
python 复制代码
class StaticHTMLRenderer(TemplateHTMLRenderer):
    """
    An HTML renderer class that simply returns pre-rendered HTML.

    The data supplied to the Response object should be a string representing
    the pre-rendered HTML content.

    For example:
        data = '<html><body>example</body></html>'
        return Response(data)

    For template rendered HTML, see TemplateHTMLRenderer.
    """
    media_type = 'text/html'
    format = 'html'
    charset = 'utf-8'

HTMLFormRenderer源码

  • rest_framework.renderers
python 复制代码
class HTMLFormRenderer(BaseRenderer):
    """
    Renderers serializer data into an HTML form.

    If the serializer was instantiated without an object then this will
    return an HTML form not bound to any object,
    otherwise it will return an HTML form with the appropriate initial data
    populated from the object.

    Note that rendering of field and form errors is not currently supported.
    """
    media_type = 'text/html'
    format = 'form'
    charset = 'utf-8'

BrowsableAPIRenderer源码

  • rest_framework.renderers
python 复制代码
class BrowsableAPIRenderer(BaseRenderer):
    """
    HTML renderer used to self-document the API.
    """
    media_type = 'text/html'
    format = 'api'
    charset = 'utf-8'

AdminRenderer源码

  • rest_framework.renderers
python 复制代码
class AdminRenderer(BrowsableAPIRenderer):
    template = 'rest_framework/admin.html'
    format = 'admin'

DocumentationRenderer源码

  • rest_framework.renderers
python 复制代码
class DocumentationRenderer(BaseRenderer):
    media_type = 'text/html'
    format = 'html'
    charset = 'utf-8'

SchemaJSRenderer源码

  • rest_framework.renderers
python 复制代码
class SchemaJSRenderer(BaseRenderer):
    media_type = 'application/javascript'
    format = 'javascript'
    charset = 'utf-8'

MultiPartRenderer源码

  • rest_framework.renderers
python 复制代码
class MultiPartRenderer(BaseRenderer):
    media_type = 'multipart/form-data; boundary=BoUnDaRyStRiNg'
    format = 'multipart'
    charset = 'utf-8'

CoreJSONRenderer源码

  • rest_framework.renderers
python 复制代码
class CoreJSONRenderer(BaseRenderer):
    media_type = 'application/coreapi+json'
    charset = None
    format = 'corejson'

全局渲染器配置示例

python 复制代码
REST_FRAMEWORK = {
	'DEFAULT_RENDERER_CLASSES': [
        'rest_framework.renderers.JSONRenderer',
        'rest_framework.renderers.BrowsableAPIRenderer',
    ]
}

局部解析器配置示例

python 复制代码
from django.contrib.auth.models import User
from rest_framework.renderers import JSONRenderer
from rest_framework.response import Response
from rest_framework.views import APIView

class UserCountView(APIView):
    """
    A view that returns the count of active users in JSON.
    """
    renderer_classes = [JSONRenderer]

    def get(self, request, format=None):
        user_count = User.objects.filter(active=True).count()
        content = {'user_count': user_count}
        return Response(content)

基于函数视图的解析器配置示例

python 复制代码
from rest_framework.decorators import api_view, renderer_classes
from rest_framework.response import Response
from myproject.models import User


@api_view(['GET'])
@renderer_classes([JSONRenderer])
def user_count_view(request, format=None):
    """
    A view that returns the count of active users in JSON.
    """
    user_count = User.objects.filter(active=True).count()
    content = {'user_count': user_count}
    return Response(content)

自定义渲染器示例

  • data 请求数据,由 Response() 实例化设置。
  • accepted_media_type 内容协商阶段确定的可接受的媒体类型。
  • renderer_context 视图提供的上下文信息字典。
python 复制代码
from django.utils.encoding import smart_unicode
from rest_framework import renderers


class PlainTextRenderer(renderers.BaseRenderer):
    media_type = 'text/plain'
    format = 'txt'

    def render(self, data, media_type=None, renderer_context=None):
        return data.encode(self.charset)

高级渲染器用法

python 复制代码
from rest_framework.decorators import api_view, renderer_classes
from rest_framework.response import Response
from myproject.models import User
from myproject.serializer import UserSerializer


@api_view(('GET',))
@renderer_classes((TemplateHTMLRenderer, JSONRenderer))
def list_users(request):
    """
    可以返回系统中用户的 JSON 或 HTML 表示的视图。
    """
    queryset = Users.objects.filter(active=True)

    if request.accepted_renderer.format == 'html':
	    # TemplateHTMLRenderer 采用上下文字典,并且还需要 template_name 名称。
	    # 它不需要序列化。
        data = {'users': queryset}
        return Response(data, template_name='list_users.html')

    # JSONRenderer 需要正常的序列化数据。
    serializer = UserSerializer(instance=queryset)
    data = serializer.data
    return Response(data)
相关推荐
言之。19 小时前
Django中的软删除
数据库·django·sqlite
java1234_小锋21 小时前
[免费]基于Python的协同过滤电影推荐系统(Django+Vue+sqlite+爬虫)【论文+源码+SQL脚本】
python·django·电影推荐系统·协同过滤
百锦再1 天前
脚本语言的大浪淘沙或百花争艳
java·开发语言·人工智能·python·django·virtualenv·pygame
dreams_dream1 天前
企业级 Django 日志配置示例
数据库·django·sqlite
计算机学长felix1 天前
基于Django的“酒店推荐系统”设计与开发(源码+数据库+文档+PPT)
数据库·python·mysql·django·vue
言之。1 天前
深入解析Django重定向机制
数据库·django·sqlite
BYSJMG1 天前
计算机毕业设计选题:基于Spark+Hadoop的健康饮食营养数据分析系统【源码+文档+调试】
大数据·vue.js·hadoop·分布式·spark·django·课程设计
计算机毕业设计木哥2 天前
计算机毕业设计 基于Python+Django的医疗数据分析系统
开发语言·hadoop·后端·python·spark·django·课程设计
XiaoMu_0012 天前
基于Django+Vue3+YOLO的智能气象检测系统
python·yolo·django
计算机毕业设计木哥2 天前
计算机毕设选题:基于Python+Django的B站数据分析系统的设计与实现【源码+文档+调试】
java·开发语言·后端·python·spark·django·课程设计