KNOX-3171 - Remove trailing slash for yarn proxy rewrite

[Kimahriman]

(It is very important that you created an Apache Knox JIRA for this change and that the PR title/commit message includes the Apache Knox JIRA ID!)

What changes were proposed in this pull request?

Remove trailing slash is YARN proxy rewrite rules which now cause issues with Spark 4.0.0 UI. I don't see any other rewrite rules for YARN including a trailing slash, so not sure why the proxy ones ever needed to.

(Please fill in changes proposed in this fix)

How was this patch tested?

Manual tested locally.

Before:

After:

Please review Knox Contributing Process before opening a pull request.

[smolnar82]

Hi @moresandeep !

Whenever you have time, can you please review this change?

Thanks!

[smolnar82]

@Kimahriman - I see you modified both 2.7.0 and 3.0.0 too. Does it mean you tested both versions?

[Kimahriman]

@Kimahriman - I see you modified both 2.7.0 and 3.0.0 too. Does it mean you tested both versions?

3.0.0 is for the V2 UI, and yeah confirmed it also has the issue and this also fixes in the same way.

[moresandeep]

@Kimahriman looks like this is for newer version of Yarn instead of updating 3.0.0 can you create a new version 4.0.0 and make changes there? We want to make sure that older version work as well and there is no regression.

[Kimahriman]

It's not related to the version of YARN, it's a new version of spark that hits an edge case that has probably always existed. I don't see why you would ever want to insert a trailing slash when it didn't already exist, and I don't see any of the other rewrites for either of those services that do the same thing