python-需要帮助来处理Google App Engine Blobstore的上传表单

我正在尝试学习blobstore API …,我能够成功上传文件并将其取回,但是我没有运气尝试将上传表单与常规网络表单结合使用,从而能够关联其他功能文件的相关信息,例如文件的昵称.

以下是我一直在玩的一个简单应用程序的代码.它基于google提供的示例.

#!/usr/bin/env python
#

import os
import urllib

from google.appengine.ext import blobstore
from google.appengine.ext import webapp
from google.appengine.ext.webapp import blobstore_handlers
from google.appengine.ext.webapp import template
from google.appengine.ext.webapp.util import run_wsgi_app
from google.appengine.ext import db

class StoredFiles(db.Model):
    nickname = db.StringProperty()
    blobkey = blobstore.BlobReferenceProperty()

    @staticmethod
    def get_all():
        query = db.Query(StoredFiles)
        files = query.get()

        return files


def doRender(handler, page, templatevalues=None):
    path = os.path.join(os.path.dirname(__file__), page)
    handler.response.out.write(template.render(path, templatevalues))

class MainHandler(webapp.RequestHandler):
    def get(self):

        allfiles = StoredFiles.get_all()

        upload_url = blobstore.create_upload_url('/upload')

        templatevalues = {
                'allfiles': allfiles,
                'upload_url': upload_url,

            }
        doRender(self, 'index.html', templatevalues)

class UploadHandler(blobstore_handlers.BlobstoreUploadHandler):
    def post(self):
        upload_files = self.get_uploads('file')
        blob_info = upload_files[0]

        self.redirect('/save/%s' % blob_info.key())

class SaveHandler(webapp.RequestHandler):

    def get(self, resource):

        newFile = StoredFiles()
        newFile.nickname = self.request.get('nickname')
        resource = str(urllib.unquote(resource))
        newFile.blobkey = resource

        newFile.put()

        self.redirect('/')

class ServeHandler(blobstore_handlers.BlobstoreDownloadHandler):
    def get(self, resource):
        resource = str(urllib.unquote(resource))
        blob_info = blobstore.BlobInfo.get(resource)
        self.send_blob(blob_info)

def main():
    application = webapp.WSGIApplication(
          [('/', MainHandler),
           ('/upload', UploadHandler),
           ('/save/([^/]+)?', SaveHandler),
          ], debug=True)
    run_wsgi_app(application)

if __name__ == '__main__':
  main()

根据文档,blobstore处理程序应该通过blob键传递,并将表单的其余部分传递给该处理程序,并将其重定向到… blob键可以正常通过,但是没有其他方法.

有人可以指出我要搞砸的地方,还是可以指向介绍此用例的优秀教程？

解决方法:

问题是当您将请求重定向到“ / save /％s”时,您发布的表单数据会丢失,这很正常.

而不是重定向,您应该将代码放在UploadHandler中,如下所示(未经测试的代码)：

class UploadHandler(blobstore_handlers.BlobstoreUploadHandler):
    def post(self):
        try:
            upload_files = self.get_uploads('file')
            blob_info = upload_files[0]

            newFile = StoredFiles()
            newFile.nickname = self.request.get('nickname')
            newFile.blobkey = blob_info.key()
            newFile.put()

            self.redirect('/')
        except:
            self.redirect('/upload_failure.html')

请参阅文档中的此页面,以获取类似示例：http://code.google.com/appengine/docs/python/tools/webapp/blobstorehandlers.html#BlobstoreUploadHandler

标签：blobstore,google-app-engine,python
来源： https://codeday.me/bug/20191105/1997505.html