需要使用Google App Engine處理上傳表單的幫助Blobstore

Question

我正在嘗試學習blobstore API ...並且我能夠成功上傳文件並將它們還原回來，但我沒有嘗試將其合併一個帶有常規web窗體的上傳表單，能夠與文件關聯額外信息，例如文件的暱稱。

以下是我一直在玩的簡單應用程序的代碼。它基於谷歌提供的示例。

#!/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() 

根據該文檔，Blob存儲區進行處理程序應該通過Blob鍵和表格的其餘部分其重定向到... Blob鍵通就好傳來的處理程序，但沒有別的是。

有人可以指出我搞亂了什麼或指向我描述這個用例的好教程嗎？

Answer 1

問題是，當您將請求重定向到「/ save /％s」時，發佈的表單數據會丟失，這是正常的。

而不是重定向的，你應該把你的代碼中UploadHandler，像這樣（未測試的代碼）：

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') 

一個類似的例子請參閱從文檔此頁：http://code.google.com/appengine/docs/python/tools/webapp/blobstorehandlers.html#BlobstoreUploadHandler