Problems uploading blobs onto App Engine

Question

Hi i'm trying to upload some mp3s as blobs using the Complete Sample App code provided in the App Engine tutorial here and i'm getting the following error `HTTP ERROR 404

Problem accessing /_ah/upload/ag5jb2xsZWN0aXZlZ3dhcHIbCxIVX19CbG9iVXBsb2FkU2Vzc2lvbl9fGHQM. Reason:

No upload session: ag5jb2xsZWN0aXZlZ3dhcHIbCxIVX19CbG9iVXBsb2FkU2Vzc2lvbl9fGHQM`

Anyone have any ideas why i'm getting this? Tried running locally and even tried deploying the App and still having issues!

score 2 · Answer 1 · answered Apr 28 '12 at 19:43

2

Do not press the back botton and try to upload file.Use to hit the url in browser every time.

answered Apr 28 '12 at 19:43

soumitra chatterjee

2,268
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What I want is to press back button and try to upload the next file? So what is the solution for it? And how to display the image in a new tab instead of the same page? – Samitha Chathuranga Mar 07 '14 at 06:36

score 1 · Answer 2 · answered Mar 17 '14 at 14:04

For each upload of file to the blob, the blob url is unique. For the first time, when you upload a file, you might be creating one blob url, using

blobstoreService.createUploadUrl("/yourServerURL");

Now, when you try to upload next file, you are clicking back button and you are trying to use the same blob session which you have created for the first file. That is the reason, you are facing the "No upload Session" error.

The solution could be, you can create a new blob url when you click the back button. Do some work around to create a new blob url upon clicking the back button.

Hope this helps.

Thanks.

score 0 · Accepted Answer · answered Apr 12 '11 at 19:48

0

Seems to be a bug with SDK 1.4.3 This seems to work just fine with SDK 1.4.2

Does this resolve your problem?

answered Apr 12 '11 at 19:48

user704785

16

I have app engine SDK 1.8.8 and I still have the same error. It works fine at the first file upload. But when I try to upload another image, by going back one step on the browser to the uploading page, above error massage is shown. It seems that no servelets are run when I try to upload the 2nd one. By the jsp itself , the error gives. Please help. – Samitha Chathuranga Mar 07 '14 at 06:33

Problems uploading blobs onto App Engine

3 Answers3