Consistent Issue getting HTTP Header using preRenderView

[NCIDevRonR]

In our application, we go through a pre-render step, get a subjectDN value from the header when our user opens the app, and we authenticate the user from there, then navigate to the first application page. From the day I first inherited our codebase in PrimeFaces version 6.2 through our current updates in PF version 14, we've had this issue where if the user navigates super-fast to our page, they see our error screen. If they reload the page right after, they see our main screen. I've reproduced our issue here. What can I do to resolve this?

[melloware]

1. PreRenderView was the old way you might want to try ViewAction instead see BalusC's explanation: https://stackoverflow.com/a/9844616/502366 or a better one: https://stackoverflow.com/a/6377957/502366

2. What do you mean by navigates super fast?

[NCIDevRonR]

I mean if I set up the same header in the browser that the filter expects, I can get different results depending on how soon after I open my browser I attempt to navigate to the test app. If I wait a few seconds, I get the welcome screen. If I navigate as soon as the browser comes up, I get the error screen.

[melloware]

have you debugged the Filter with log lines to see whether the header is set or not? The Filter in theory should RUN before the JSF code in your preRenderView (in theory).

[NCIDevRonR]

I've just added a System.out to check subjectDN for null just before the if, and I see what I expected to see. When I navigate quickly to the page, there's a null in subjectDN and I see the error page, and when I wait a few seconds before navigating onto the page, subjectDN is populated, and I see the welcome page.

[NCIDevRonR]

I have updated my test app with a ViewAction, and I've set it up to retry 15 times if the subjectDN handshake fails. The original issue still exits. If the user navigates immediately upon opening the browser, the back-end tries 15 times unsuccessfully to handshake with subjectDN. If the user waits five seconds after opening the browser and then navigates to the test page, the back-end succeeds in handshaking with subjectDN the first time. Is there a way to rewrite the retry loop, to maximize the likelihood of a successful retry?

[melloware]

not sure i still can't explain why that is even happening.