Generate blob upload URL from Blob Key googleblobstore

Question

I am trying to upload blob to google blob store I am using this method to get upload Key

BlobKey key = blobstoreService.createGsBlobKey("/gs/saad");

I wonder how to create upload URL from this key ?

I know that i can get URL directly using the line bellow

String blobUploadUrl = blobstoreService.createUploadUrl("/saad");

but in this case I can't get the blob key which I need to store in my database in order to be able to download the file later.

Answer 1

You're going about this the wrong way. You don't create a BlobKey first, you retrieve the key after uploading.

So you will:

1- Create an upload URL:

String blobUploadUrl = blobstoreService.createUploadUrl("/saad");

2- Upload to the URL (POST from your app/form).

3- After the upload, /saad will be called automatically. You should have a POST handler mapped to /saad. From there, you retrieve the blobs uploaded from the HttpServletRequest object using blobstoreService.getBlobInfos(request) or blobstoreService.getUploads(request).

See Uploading a blob for more info.