[web2py] Check upload file size before actual file data uploading

[Exeption]

Hi,

Already have asked 
here<http://stackoverflow.com/questions/12668310/check-upload-file-size-before-actual-file-data-uploading>,
 
but no reply.

I will duplicate my question here:

In my web2py controller I'm accessing file data like:

vfile = request.post_vars.video.file

But how can I check Content-Length *before* actual file data will be 
uploaded? It is not a good idea for me to check file size after file 
already uploaded.

NOTE: I'm not using FORM() helper and database but just raw regular file 
upload. Is there any way to hook into web2py internals to do what I need?


Thanks!

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