Can't read files from BlobStore

Question

I have been trying to write and read files directly from the BlobStore, but it just doesnt work. The issue is I open the file like file = fileService.getBlobFile(blobKey); and it doesn't throw any exception but right in the next line I call readChannel = fileService.openReadChannel(file, false); and that one throws a FileNotFoundException.

I'm confused as to why the first line did not throw the exception.

Here is the same issue

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Answer 1

I haven't had any problems with writes or deletes, but I too get a FileNotFoundException when using openReadChannel(...) with an AppEngineFile.

I've tried using an AppEngineFile created from its constructor taking a complete path. I've tried using an AppEngineFile obtained from getBlobFile(...) like you do above. Either way, when the AppEngineFile is passed to openReadChannel(...) a FileNotFoundException is thrown.

My workaround was to let BlobstoreService.serve(...) do all the work of reading and sending the file. I suspect that using the FileService to read from an AppEngineFile isn't supported yet (I'm using 1.6.0), so reads must be done via the BlobstoreService (serve(...), fetchData(...), BlobstoreInputStream).