Full file SHA256 checksum? about tus-ruby-server HOT 5 CLOSED

I implemented a custom storage backend for all this which was the easiest way IMHO.

Resumable SHA256 can be achieved by using FFI and dumping/reading the memory of the SHA256_CTX into a file to resume processing, it obviously depends on chunk order.

Thanks for your support and implementation of the server!

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If all individual chunks passed checksum validation, doesn't that mean the whole upload passed it too? Why is additionally validating the total checksum at the end needed?

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Thanks for the fast reply!

It is meant for post-processing and later reference - i.e. we keep the checksum in a journal, use it for signing the document etc in the application. It is not meant for validating the upload but rather for later usage in the application where it would be very handy to have it computed on the fly instead of having to do a full pass later on when the file is uploaded.

We did use the nginx-upload-module which provides this (but does not provide chunk based resumable upload) so I'm looking into a way to provide this as well.

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Aha, I understand. For the request body IO objects that are rewindable (depends on the web server and its configuration), a hook triggered after upload might work. The only thing is that I don't know how you would resume calculating the hash between requests.

Alternatively, it could be possible to override the #patch_file method on the storage object, and update the info hash passed as the argument there after upload.

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Thanks for this information - is the hook "after_upload" already available?

Resume calculating the hash would work by dumping/reading the OpenSSL SHA256_CTX context but I see now that with ruby, I can not get hold of it in an easy way..

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