如何使用 Django REST Framework 返回生成的文件下载？

Question

我需要将生成的文件下载作为 Django REST Framework 响应返回。我尝试了以下方法：

def retrieve(self, request, *args, **kwargs):
    template = webodt.ODFTemplate('test.odt')
    queryset = Pupils.objects.get(id=kwargs['pk'])
    serializer = StudentSerializer(queryset)
    context = dict(serializer.data)
    document = template.render(Context(context))
    doc = converter().convert(document, format='doc')
    res = HttpResponse(
        FileWrapper(doc),
        content_type='application/msword'
    )
    res['Content-Disposition'] = u'attachment; filename="%s_%s.zip"' % (context[u'surname'], context[u'name'])
    return res

但它返回一个 msword 文档为json。

如何让它开始作为文件下载？

Answer 1

这是一个直接从 DRF 返回文件下载的示例。诀窍是使用自定义渲染器，以便您可以直接从视图返回响应：

from django.http import FileResponse
from rest_framework import viewsets, renderers
from rest_framework.decorators import action

class PassthroughRenderer(renderers.BaseRenderer):
    """
        Return data as-is. View should supply a Response.
    """
    media_type = ''
    format = ''
    def render(self, data, accepted_media_type=None, renderer_context=None):
        return data

class ExampleViewSet(viewsets.ReadOnlyModelViewSet):
    queryset = Example.objects.all()

    @action(methods=['get'], detail=True, renderer_classes=(PassthroughRenderer,))
    def download(self, *args, **kwargs):
        instance = self.get_object()

        # get an open file handle (I'm just using a file attached to the model for this example):
        file_handle = instance.file.open()

        # send file
        response = FileResponse(file_handle, content_type='whatever')
        response['Content-Length'] = instance.file.size
        response['Content-Disposition'] = 'attachment; filename="%s"' % instance.file.name

        return response

请注意，我使用的是自定义端点 download 而不是默认端点 retrieve，因为这样可以很容易地仅为此端点而不是整个视图集覆盖渲染器——而且它往往是有意义的对于列表和详细信息，无论如何都会返回常规 JSON。如果您想有选择地返回文件下载，您可以向自定义渲染器添加更多逻辑。

Answer 2

这可能对你有用：

file_path = file_url
FilePointer = open(file_path,"r")
response = HttpResponse(FilePointer,content_type='application/msword')
response['Content-Disposition'] = 'attachment; filename=NameOfFile'

return response.

前端代码请参考this

Answer 3

我正在使用 DRF，我找到了一个下载文件的视图代码，就像

from rest_framework import generics
from django.http import HttpResponse
from wsgiref.util import FileWrapper

class FileDownloadListAPIView(generics.ListAPIView):

    def get(self, request, id, format=None):
        queryset = Example.objects.get(id=id)
        file_handle = queryset.file.path
        document = open(file_handle, 'rb')
        response = HttpResponse(FileWrapper(document), content_type='application/msword')
        response['Content-Disposition'] = 'attachment; filename="%s"' % queryset.file.name
        return response

而 url.py 将是

path('download/<int:id>/',FileDownloadListAPIView.as_view())

我在前端使用 React.js，我得到了类似的响应

handleDownload(id, filename) {
  fetch(`http://127.0.0.1:8000/example/download/${id}/`).then(
    response => {
      response.blob().then(blob => {
      let url = window.URL.createObjectURL(blob);
      let a = document.createElement("a");
      console.log(url);
      a.href = url;
      a.download = filename;
      a.click();
    });
  });
}

在我成功下载了一个也可以正确打开的文件之后，我希望这能正常工作。谢谢

Answer 4

我通过将文件保存在媒体文件夹中并将其链接发送到前端解决了我的问题。

@permission_classes((permissions.IsAdminUser,))
class StudentDocxViewSet(mixins.RetrieveModelMixin, viewsets.GenericViewSet):
    def retrieve(self, request, *args, **kwargs):
        template = webodt.ODFTemplate('test.odt')
        queryset = Pupils.objects.get(id=kwargs['pk'])
        serializer = StudentSerializer(queryset)
        context = dict(serializer.data)
        document = template.render(Context(context))
        doc = converter().convert(document, format='doc')
        p = u'docs/cards/%s/%s_%s.doc' % (datetime.now().date(), context[u'surname'], context[u'name'])
        path = default_storage.save(p, doc)
        return response.Response(u'/media/' + path)

并像在我的前端（AngularJS SPA）中一样处理这个

$http(req).success(function (url) {
    console.log(url);
    window.location = url;
})

Answer 5

对我来说，使用 Python 3.6、Django 3.0 和 DRF 3.10，问题来自使用错误的响应类型。我需要使用django.http.HttpResponse，如下所示：

from django.http import HttpResponse
...
with open('file.csv', 'r') as file:
    response = HttpResponse(file, content_type='text/csv')
    response['Content-Disposition'] = 'attachment; filename=file.csv'
    return response

Answer 6

在models.py中

class Attachment(models.Model):
    file = models.FileField(upload_to=attachment_directory_path, blank=True, null=True)
    ...

    @property
    def filename(self):
        return self.file.name.split('/')[-1:][0]

在views.py中

import mimetypes
from django.http import FileResponse


class AttachmentViewSet(ModelViewSet):
    ...

    @action(methods=['GET'], detail=True)
    def download(self, request, **kwargs):
        att = self.get_object()
        file_handle = att.file.open()

        mimetype, _ = mimetypes.guess_type(att.file.path)
        response = FileResponse(file_handle, content_type=mimetype)
        response['Content-Length'] = att.file.size
        response['Content-Disposition'] = "attachment; filename={}".format(att.filename)
        return response

在前端，我使用 axios 下载文件。 api 是 axios 客户端。

export function fileDownload(url, filename){
  return api.get(url, { responseType: 'blob' })
    .then((response)=>{
      const url = window.URL.createObjectURL(new Blob([response.data]));
      const link = document.createElement('a');
      link.href = url;
      link.setAttribute('download', filename);
      document.body.appendChild(link);
      link.click();
    })
}

希望对你有帮助