Upload a file in Google App Engine and making it downloadable

问题

I am new with google app engine and I want to use it as a server to enable people download a file. I have gone through the tutorials in python. I didnt find anything to actually guide me how to upload files to the server for this purpose.

回答1:

The Blobstore tutorial gives an example for just this use case. That link provides this code: an application that lets users upload files and then immediately download them:

#!/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

class MainHandler(webapp.RequestHandler):
    def get(self):
        upload_url = blobstore.create_upload_url('/upload')
        self.response.out.write('<html><body>')
        self.response.out.write('<form action="%s" method="POST" enctype="multipart/form-data">' % upload_url)
        self.response.out.write("""Upload File: <input type="file" name="file"><br> <input type="submit" 
            name="submit" value="Submit"> </form></body></html>""")

class UploadHandler(blobstore_handlers.BlobstoreUploadHandler):
    def post(self):
        upload_files = self.get_uploads('file')  # 'file' is file upload field in the form
        blob_info = upload_files[0]
        self.redirect('/serve/%s' % blob_info.key())

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),
           ('/serve/([^/]+)?', ServeHandler),
          ], debug=True)
    run_wsgi_app(application)

if __name__ == '__main__':
  main()

回答2:

You can also check in a very good GAE/python app from Nick Johnson's blog that has a nice interface and also enables multiple uploads if you need. I've taken that code to build for my apps that need something like a file system and managing blobs solves that.

来源：https://stackoverflow.com/questions/8498771/upload-a-file-in-google-app-engine-and-making-it-downloadable

标签

python

google-app-engine

blobstore