[SPARK-11338][WebUI] Prepend app links on HistoryPage with uiRoot path

[ckadner]

SPARK-11338: HistoryPage not multi-tenancy enabled ...

• HistoryPage.scala ...prepending all page links with the web proxy (uiRoot) path
• HistoryServerSuite.scala ...adding a test case to verify all site-relative links are prefixed when the environment variable APPLICATION_WEB_PROXY_BASE (or System property spark.ui.proxyBase) is set

[BryanCutler]

I took a look, LGTM

[holdenk]

I've taken a first look, and it looks good pending tests. Could maybe @andrewor14 or @vanzin or @tsudukim take a look (since it seems like you are some of the more recent contributors to this part of the history server) / whitelist or trigger jenkins tests

[holdenk]

@ckadner one question is would it make sense to simply always prepend inside of makepagelink instead of doing this change everywhere? Looking at the other pages though it seems that most them do it this way so maybe there is a good reason.

[vanzin]

+1 to @holdenk's comment. If you're changing all invocations of makePageLink it might be easier to just change makePageLink itself.

[andrewor14]

ok to test

[SparkQA]

Test build #44589 has finished for PR 9291 at commit 8bcb3dc.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[ckadner]

@holdenk @vanzin, thank you for your comments! I just pushed an update to my fix.

[SparkQA]

Test build #44618 has finished for PR 9291 at commit d054bd7.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[ckadner]

@vanzin, @andrewor14, if you are okay with this fix, do you think it could still make it into 1.6?

[vanzin]

nit: this line should be indented now.

[vanzin]

Couple of nits, otherwise LGTM.

[ckadner]

@vanzin -- I pushed the nit pickity fixes 🔍 -- Thanks :-)

[SparkQA]

Test build #44754 has finished for PR 9291 at commit 01d2f35.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[vanzin]

Merging to master.

[ckadner]

@vanzin -- Thank you!