FileSystem API was introduced in AppEngine last year. A great feature. I tried using it more than a couple of times and ended up with one problem or the other. Some of the notable issues include:
- What should be the filename during create and save? The name given during create was only name-part and cannot be used during read. Read must use fullpath.
- If you use fullpath, you cannot use it to delete the file.
After a bunch of experiments, I concluded that it is best to use BlobKey
.