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Question

I am trying to create a webservice which will send and receive large files, as part of a storage solution for remote backups.

When a request is received by the webserver it needs to be authenticated before it stores the data.

At the moment I'm considering sending sending authentication methods in the headers and the actual content in the body. Fairly standard.

However I would like to know, due to the size of the body, if it is possible to authenticate the headers, and possibly respond to the request/drop the connection before completely receiving the body, if the request cannot be validated?

I haven't started implementing yet, but I am leaning towards an implementation using Golang. There will be an nginx server in front of it, in case it makes any difference.

Edit:

Maybe I haven't been clear enough, in my original question, but the main focus should be: Is it possible to figure out if a request is authenticated before receiving the entire payload and possibly drop the connection/respond if that is not the case?

Like.. Is it possible to interpret the request as a stream, where you can act on just the first part, even though the rest of the payload hasn't arrived yet.

Sorry for the confusion.

Answer 1

If you post the file as the body of your request you can use an auth header to validate without waiting for the file to fully upload.

You can then use io.Copy to copy from the request body to a file.

_, err := io.Copy(someFile, req.Body)

Don't use 'multipart/form-data' the http pkg will get in your way if you do. Posting the file as the body will let you access the contents of the request body as a stream and io.Copy will manage the copy to the file in a sensible way.