Google App Engine Photo Upload Using Blobstore - Python

gistfile1.py

import webapp2
import jinja2
import os
from google.appengine.ext import blobstore
from google.appengine.ext.webapp import blobstore_handlers
from models import UserPicfayAsset
import json

jinja_environment = jinja2.Environment(autoescape=True,
                                       loader=jinja2.FileSystemLoader(
	                                       os.path.join(os.path.dirname(__file__), 'templates')))

class PhotoUploadFormHandler(webapp2.RequestHandler):
    def get(self):
        upload_url = blobstore.create_upload_url('/upload_photo')

        self.response.headers['Content-Type'] = 'application/json'
        obj = {
            'uploadURL': upload_url
        }
        self.response.out.write(json.dumps(obj))


class PhotoUploadHandler(blobstore_handlers.BlobstoreUploadHandler):
    def post(self):
        try:
            upload = self.get_uploads()[0]

            user_photo = UserPicfayAsset(blob_key=upload.key())
            user_photo.put()

            self.response.headers['Content-Type'] = 'application/json'
            obj = {'imageURL': ('/view_photo/%s' % upload.key())}
            self.response.out.write(json.dumps(obj))

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


class ViewPhotoHandler(blobstore_handlers.BlobstoreDownloadHandler):
    def get(self, photo_key):
        if not blobstore.get(photo_key):
            self.error(404)
        else:
            self.send_blob(photo_key)


app = webapp2.WSGIApplication([
    ('/upload_photo', PhotoUploadHandler),
    ('/upload_url', PhotoUploadFormHandler),
    ('/view_photo/([^/]+)?', ViewPhotoHandler)
], debug=False)