[JENKINS-60393] Ensure all plugins are loaded to configure the defaults

[Dohbedoh]

See JENKINS-60393: the configuration of the defaults in the constructor of the GlobalConfiguration may cause the loading to fail on startup in some cases

Proposed changelog entries

• Ensure all plugin are loaded before setting global defaults

Submitter checklist

• JIRA issue is well described
• Changelog entry appropriate for the audience affected by the change (users or developer, depending on the change).
  * Use the Internal: prefix if the change has no user-visible impact (API, test frameworks, etc.)
• Appropriate autotests or explanation to why this change has no tests

@fcojfernandez @rsandell

[varyvol]

The change looks good, but given this comes from a bug I think it's worth to have an automated test.

[fcojfernandez]

@Dohbedoh I've been doing some testing and I've found weird this:

1. Install from scratch
2. Go to Manage Jenkins > Configure and remove all the Health Metrics
3. Save
4. Enter again. The Health Metrics are there again

Shouldn't they be removed?

[rsandell]

I don't remember the implications of having both after and before rules in the same initializer. But I guess you've verified it works as intended?

[Dohbedoh]

I have tested this yes. I am not sure how to create a test for the initialization though ?
The real fix is to perform the auto configuration outside the constructor and when plugins are loaded: after = InitMilestone.EXTENSIONS_AUGMENTED. I do believe that this is enough. I added the before = InitMilestone.JOB_LOADED because I feel this is consistent (the global metrics will be used on Folder's creation)

[Dohbedoh]

@fcojfernandez You are right. Apparently when you remove all metrics, no healthMetrics attributes is included in the JSON at all. And the bind just does nothing. I need to override the GlobalConfiguration#configure method.

[Dohbedoh]

@varyvol @rsandell @fcojfernandez any idea how I can write a test for the component initialization problem ?

[varyvol]

@Dohbedoh I think if you tried to create a folder, then something was logged? I'd say that's what you need to automate.

[rsandell]

Missed save() ?

Maybe simpler to

this.setHealthMetrics(Collections.emptyList());
req.bindJSON(this, json);
this.save();

?

[rsandell]

ah I see now the call to save() in setHealthMetrics

[Dohbedoh]

yeah this would save() twice

[fcojfernandez]

Manual testing seems to be OK. @varyvol 's comment is the only one missing:

@Dohbedoh I think if you tried to create a folder, then something was logged? I'd say that's what you need to automate.

[Dohbedoh]

We would need to cause the circular dependency first though. It cause the component to not be loaded (AbstractFolderConfiguration#get thows an IllegalStateException). So maybe I can create an anonymous class with an @Initializer to cause this ?