[JENKINS-71244] Avoid relative link in update center

[Bananeweizen]

See JENKINS-71244.

• convert the relative link to an absolute one, since it might be used in different contexts
• update all message bundles to use the new format argument

Note: To my mind, all relative URLs in properties files are a bad design choice, since the related code may be used from different context URLs. It would probably be rather easy to detect such issues with a regex checkstyle rule looking for href=". in properties files. If core maintainers agree, I could raise a separate issue for that.

Testing done

I've run a developer instance with this change. But I have not been able to force the update center error on my local machine. So Jenkins still runs, but the actual change is untested.

Proposed changelog entries

• JENKINS-71244: Fix update center proxy configuration hyperlink in error messages

Proposed upgrade guidelines

N/A

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[NotMyFault]

Thanks for the PR! I have tested issue described on the master branch via

diff --git a/core/src/main/java/hudson/model/UpdateCenter.java b/core/src/main/java/hudson/model/UpdateCenter.java
index b9ca1d2001..7fb5a2ce89 100644
--- a/core/src/main/java/hudson/model/UpdateCenter.java
+++ b/core/src/main/java/hudson/model/UpdateCenter.java
@@ -1680,6 +1680,7 @@ public class UpdateCenter extends AbstractModelObject implements Saveable, OnMas
 
                 connectionStates.put(ConnectionStatus.UPDATE_SITE, ConnectionStatus.CHECKING);
                 statuses.add(Messages.UpdateCenter_Status_CheckingJavaNet());
+                statuses.add(Messages.UpdateCenter_Status_UnknownHostException("yo"));
 
                 config.checkUpdateCenter(this, site.getUrl());
 

to replicate the problem the issue linked describes, without messing with networking.
The URL to the proxy configuration page is resolved properly:

I'm not confident this PR addresses an actual issue, given I can't replicate the issue described.

[Bananeweizen]

@NotMyFault I'm not exactly sure, but it looks like you are on the main page of the update center when trying to reproduce, right? If I remember it right from the issue, I was actually installing updates (i.e. my screenshot shows pluginManager/updates). Since that error message can appear on pages with different depth from the root, a fixed relative address (as before the patch) cannot work in all cases.

[NotMyFault]

I was actually installing updates

I see, you were on /manage/pluginManager/updates/. On this view, I can replicate the issue with the patch I added above, on the master branch and verify the change proposed working.

I recommend removing the leading slash in the .properties files because Jenkins.get().getRootUrl() adds a trailing slash to all URLs creating a double slash: http://localhost:8085//manage/pluginManager/advanced

[Bananeweizen]

I recommend removing the leading slash in the .properties files because Jenkins.get().getRootUrl() adds a trailing slash to all URLs creating a double slash: http://localhost:8085//manage/pluginManager/advanced

Done. I also like it when such things are cleaned up. :) And I'll have to remember your trick of not even fiddling with the network if it's easily possible to just trigger the error condition in (additional) code. Thanks for that.

I didn't rebase, assuming that simplifies your review and you'll probably rebase on submit anyway. Please tell me if that doesn't fit to typical Jenkins project workflows.

[NotMyFault]

I didn't rebase, assuming that simplifies your review and you'll probably rebase on submit anyway. Please tell me if that doesn't fit to typical Jenkins project workflows.

No worries, all good. We don't do that during the review phase, given it detaches code comments, slows the time-to-merge down for no good reason, and generally causes more harm than good.
To maintain a clean history, PRs are squashed, typically.

[timja]

.

[timja]

/label ready-for-merge

---

This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!

[daniel-beck]

This breaks links when the UI is not accessed through the configured root URL.

[NotMyFault]

This breaks links when the UI is not accessed through the configured root URL.

Would you recommend a change independent of #getRootUrl?

[daniel-beck]

Would you recommend a change independent of #getRootUrl?

This should use Jenkins#getRootUrlFromRequest, or StaplerRequest#getContextPath (like the Jelly variable rootURL).

[daniel-beck]

This should use Jenkins#getRootUrlFromRequest, or StaplerRequest#getContextPath (like the Jelly variable rootURL).

JENKINS-71905 documents the problem this change causes.

FTR using #getRootUrlFromRequest would also be incorrect, as the full error message is kinda persisted and not recomputed in every request. StaplerRequest#getContextPath may work though, as long as nobody is crazy enough to use different context paths depending on the domain.