Is it possible for a POSTed form's data to remain intact across a form-login authentication scheme? The servlet spec says for login-form authentication, it will "save the URL path" that triggers the authentication, and use it after the user successfully is authenticated.
I'm guessing that ambiguity will lead to server mismatches--some being able to reconstruct the full request after authentication, while others only reconstruct the request but miss the message body.
On a related note, after the user gets authenticated, is there any difference between the original request and the one that you see after authentication? Will, for example, the referring URLs be identical, or will the final one be changed to reflect some bizarre authentication URL the container comes up with?
First of all, POST contains 2 types of data to worry about: the URL itself, plus the data stream that was POSTed. That's different from GET, where the URL is all you get (discounting side stuff like cookies).
Your URL may get rewritten when you authenticate to add session ID info, but the core URL should not. If you use the URL data extraction services that should make for minimal effect. If you're doing the parsing yourself, YMMV.
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