Google App Engine (Python) - Uploading a file (image)

Albraa picture Albraa · Aug 23, 2013 · Viewed 8.3k times · Source

I want the user to be able to upload images to Google App Engine. I have the following (Python):

class ImageData(ndb.Model):
     name = ndb.StringProperty(indexed=False)
     image = ndb.BlobProperty()

Information is submitted by the user using a form (HTML):

<form name = "input" action = "/register" method = "post">
    name: <input type = "text" name = "name">
    image: <input type = "file" name = "image">
</form>

Which is then processed by:

class AddProduct(webapp2.RequestHandler):
    def post(self):
        imagedata = ImageData(parent=image_key(image_name))
        imagedata.name = self.request.get('name')
        imagedata.image = self.request.get('image')
        imagedata.put()

However, when I try to upload an image, lets say "Book.png", I get the error: BadValueError: Expected str, got u'Book.png'

Any idea what is going on? I have been working with GAE for quite some time, but this is the first time I had to use blobs.

I used this link: https://developers.google.com/appengine/docs/python/images/usingimages which uses db, not ndb. I also tried storing the image in a variable first like in the link: storedInfo = self.request.get('image') and then storing it: imagedata.image = ndb.Blob(storedInfo) Which ALSO gives me an error: AttributeError: 'module' object has no attribute 'Blob' Thanks in advance.

Answer

Orane picture Orane · May 28, 2014

Had the same prob.

just replace

imagedata.image = self.request.get('image')

with:

imagedata.image = str(self.request.get('image'))

also your form needs to have enctype="multipart/form-data

<form name = "input" action = "/register" method = "post" enctype="multipart/form-data">