[Zope] BUG: Conflict competing write causes loss of form input

[Jim Fulton]

"Li Dongfeng (RA of H. Wong)" wrote:
> 
> If you create new object in a form action, and the form action
> takes noticable time to finish, this bug may appear if two
> person is submitting the form simutaneously.
> One of the persons may lose his form input.
> 
> These steps can reproduce this bug:

(snip excellent research)

> In addition to the loss of form input bug,  any suggestion on
> a work around of the conflict competing write problem?

I just checked in a fix for this.  I neglected to reset
the request body (a file-like object) when retrying the
request.

The fix entailed adding:

        self.stdin.seek(0)

to the start of the HTTPRequest.retry method in
lib/python/ZPublisher/HTTPRequest.py.

Thanks for reporting this. Nice research.

Jim

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