Fix NSX SDK list handling to fetch all paginated results

[wolfchkov]

Fix for NSX plugin.

Description

NSX SDK list operations are pageable: the API returns a non-null and non-empty cursor field when more pages are available. The previous implementation only fetched the first page and ignored pagination.

This change updates the list retrieval flow to:

• follow the cursor chain until no further pages exist
• accumulate items from all pages
• return a single merged result to the caller

This ensures that list operations return the complete dataset rather than just the first page.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• [ x] Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)
• Build/CI
• [x ] Test (unit or integration test code)

Feature/Enhancement Scale or Bug Severity

Feature/Enhancement Scale

• Major
• [ x] Minor

Bug Severity

• BLOCKER
• [ x] Critical
• Major
• Minor
• Trivial

Screenshots (if appropriate):

How Has This Been Tested?

How did you try to break this feature and the system with this change?

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[codecov]

Codecov Report

❌ Patch coverage is 25.85034% with 109 lines in your changes missing coverage. Please review.
✅ Project coverage is 17.46%. Comparing base (3c64847) to head (070b956).
⚠️ Report is 471 commits behind head on main.

Files with missing lines	Patch %	Lines
...va/org/apache/cloudstack/service/NsxApiClient.java	0.00%	106 Missing ⚠️
...va/org/apache/cloudstack/service/PagedFetcher.java	92.68%	0 Missing and 3 partials ⚠️

Additional details and impacted files

@@ Coverage Diff @@## main #12241 +/- ##
============================================
+ Coverage 3.58% 17.46% +13.88% - Complexity 0 15525 +15525 
============================================
Files 445 5914 +5469 Lines 37552 529493 +491941 Branches 6914 64685 +57771 ============================================
+ Hits 1347 92488 +91141 - Misses 36039 426584 +390545 - Partials 166 10421 +10255 

Flag	Coverage Δ
uitests	3.58% <ø> (ø)
unittests	18.52% <25.85%> (?)

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[Copilot]

Pull request overview

This PR fixes NSX SDK list operations to properly handle pagination by following cursor chains until all pages are fetched. Previously, only the first page of results was retrieved, which could lead to incomplete data when the result set exceeded a single page.

Key Changes:

• Introduced a new PagedFetcher utility class that implements cursor-based pagination logic
• Updated multiple list operations in NsxApiClient to use PagedFetcher for complete result retrieval
• Added comprehensive unit tests for the pagination functionality

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
PagedFetcher.java	New utility class implementing cursor-based pagination with a fluent builder pattern for fetching all pages of results
PagedFetcherTest.java	Comprehensive unit tests covering single-page, multi-page, and edge cases for the pagination logic
NsxApiClient.java	Updated list operations (NAT rules, transport zones, segment ports, LB monitors, groups, services, etc.) to use PagedFetcher; refactored methods to return Optional for cleaner null handling; improved logging consistency

---

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[Pearl1594]

code lgtm.

[Pearl1594]

@blueorangutan package

[blueorangutan]

@Pearl1594 a [SL] Jenkins job has been kicked to build packages. It will be bundled with KVM, XenServer and VMware SystemVM templates. I'll keep you posted as I make progress.

[wolfchkov]

This fix is currently undergoing testing. When the test results are ready, I will update the description accordingly.

[blueorangutan]

Packaging result [SF]: ✔️ el8 ✔️ el9 ✔️ el10 ✔️ debian ✔️ suse15. SL-JID 16006

[nvazquez]

Hi @wolfchkov@ZhyliaievD this PR seems to be fixing the same issue as #12834. Please advise which one should be kept and we can close the other one.

[weizhouapache]

#12834 has been merged

closing this