Merge flags-refactor branch to main

[mounicasruthi]

Description

This PR merges the changes from previous flag refactor PRs as part of the ongoing effort to standardize CLI flag naming conventions across Vitess by replacing underscores (_) with dashes (-).

The motivation for this change is tracked in #17880, and the standardization helps improve consistency and align with the best practices.

This merge includes the following completed PRs:

#17964 — Refactor vstream_dynamic_packet_size and vstream_packet_size flags to use dashes

• Migrated 4 flags from _ to -
• Count before: 1488 (_) / 572 (-) → after: 1484 (_) / 576 (-)

---

#17975 — Standardize topo flags to use hyphen-based naming

• Migrated all topology-related flags (e.g., --topo-global-server-address, --topo-zk-tls-key, etc.).
• Count before: 1484 (_) / 576 (-) → after: 1366 (_) / 694 (-)
• 118 flags migrated.

---

#18009 — Refactor grpc flags for standardized naming

• Migrated all GRPC-related flags to the dashed format.
• Count before: 1366 (_) / 694 (-) → after: 1132 (_) / 948 (-)
• 234 flags migrated

---

#18064 — Refactor flags - Part 3

• Migrated a set of commonly reused flags across multiple components (appearing in ≥3 binaries).
• Count before: 1132 (_) / 948 (-) → after: 738 (_) / 1342 (-)
• 394 flags migrated

---

#18095 — Refactor flags - Part 4

• Migrated another set of commonly reused flags across multiple components (appearing in ≥3 binaries).
• Count before: 738 (_) / 1342 (-) → after: 465 (_) / 1615 (-)
• 273 flags migrated

---

Helper File

To support this migration, a new utility file go/vt/utils/flags.go was created.

• Wraps flag registration (SetFlagIntVar, SetFlagBoolVar, etc.)
• Automatically registers both dashed and underscored versions.
• Marks the underscored version as deprecated and hidden, while encouraging the dashed variant.
• Includes testing utilities to validate that both forms are handled correctly in tests.

Future Plan

As mentioned in the original proposal:

• v23 and v24 will support both _ and - variants of flags to give users time to adapt.
• v25 will remove support for underscores in flag names entirely.
• This phased approach ensures backward compatibility while allowing Vitess to make its flag usage consistent.

Related Issue(s)

#17880

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

• Ensure that the Pull Request has a descriptive title.
• Ensure there is a link to an issue (except for internal cleanup and flaky test fixes), new features should have an RFC that documents use cases and test cases.

Tests

• Bug fixes should have at least one unit or end-to-end test, enhancement and new features should have a sufficient number of tests.

Documentation

• Apply the release notes (needs details) label if users need to know about this change.
• New features should be documented.
• There should be some code comments as to why things are implemented the way they are.
• There should be a comment at the top of each new or modified test to explain what the test does.

New flags

• Is this flag really necessary?
• Flag names must be clear and intuitive, use dashes (-), and have a clear help text.

If a workflow is added or modified:

• Each item in Jobs should be named in order to mark it as required.
• If the workflow needs to be marked as required, the maintainer team must be notified.

Backward compatibility

• Protobuf changes should be wire-compatible.
• Changes to _vt tables and RPCs need to be backward compatible.
• RPC changes should be compatible with vitess-operator
• If a flag is removed, then it should also be removed from vitess-operator and arewefastyet, if used there.
• vtctl command output order should be stable and awk-able.

[codecov]

Codecov Report

Attention: Patch coverage is 78.44828% with 75 lines in your changes missing coverage. Please review.

Project coverage is 67.47%. Comparing base (c3daef3) to head (49333a0).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
go/vt/vttest/vtprocess.go	50.00%	9 Missing ⚠️
go/cmd/vtcombo/cli/main.go	0.00%	6 Missing ⚠️
go/cmd/vtgate/cli/cli.go	0.00%	6 Missing ⚠️
go/cmd/vtbackup/cli/vtbackup.go	0.00%	5 Missing ⚠️
go/vt/discovery/healthcheck.go	0.00%	4 Missing ⚠️
go/vt/utils/flags.go	93.54%	4 Missing ⚠️
go/vt/vtgate/grpcvtgateservice/server.go	20.00%	4 Missing ⚠️
go/cmd/mysqlctl/command/root.go	0.00%	3 Missing ⚠️
go/cmd/mysqlctld/cli/mysqlctld.go	0.00%	3 Missing ⚠️
go/vt/mysqlctl/mycnf_flag.go	85.00%	3 Missing ⚠️
... and 15 more

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #18280   +/-   ##
=======================================
  Coverage   67.46%   67.47%           
=======================================
  Files        1602     1603    +1     
  Lines      262245   262329   +84     
=======================================
+ Hits       176930   177010   +80     
- Misses      85315    85319    +4     

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[deepthi]

This is great! LGTM.
The only thing we are missing right now is an announcement in the release notes. That should go into https://github.com/vitessio/vitess/blob/main/changelog/23.0/23.0.0/summary.md
Technically we don't have to block this PR merge on that though. It can be done in the follow up PRs that are already queued up.

[deepthi]

@rohit-nayak-ps we need to regenerate the website docs. Should we defer that until the remaining work is complete?

[rohit-nayak-ps]

@rohit-nayak-ps we need to regenerate the website docs. Should we defer that until the remaining work is complete?

Let's defer till we have merged everything.