privilege: handle username with "@" correctly for role(RBAC) related code

[tiancaiamao]

What problem does this PR solve?

Issue Number: close #59552

Problem Summary:

What changed and how does it work?

The old code use key = username + "@" + host, and also split by "@" to get back the username.
This is not stable enough when the username itself contains "@"

Change key from username + "@" + host to {username, host} struct makes the code more robust.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[tiprow]

Hi @tiancaiamao. Thanks for your PR.

PRs from untrusted users cannot be marked as trusted with /ok-to-test in this repo meaning untrusted PR authors can never trigger tests themselves. Collaborators can still trigger tests on the PR using /test all.

I understand the commands that are listed here.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[codecov]

Codecov Report

Attention: Patch coverage is 96.77419% with 1 line in your changes missing coverage. Please review.

Project coverage is 73.4831%. Comparing base (4cf94a7) to head (7e88b0c).
Report is 4 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #59739        +/-   ##
================================================
+ Coverage   72.9611%   73.4831%   +0.5219%     
================================================
  Files          1697       1699         +2     
  Lines        468962     469633       +671     
================================================
+ Hits         342160     345101      +2941     
+ Misses       105734     103513      -2221     
+ Partials      21068      21019        -49     

Flag	Coverage Δ
integration	43.0231% <96.7741%> (?)
unit	72.2930% <96.7741%> (+0.1411%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	45.0701% <ø> (-0.0462%)	⬇️

[tiancaiamao]

/test check-dev2

[tiprow]

@tiancaiamao: Cannot trigger testing until a trusted user reviews the PR and leaves an /ok-to-test message.

Details

In response to this:

/test check-dev2

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[zimulala]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: lance6716, zimulala

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [lance6716,zimulala]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-02-25 12:57:41.356126912 +0000 UTC m=+360609.309285178: ☑️ agreed by lance6716.
• 2025-02-26 02:36:21.530089199 +0000 UTC m=+409729.483247464: ☑️ agreed by zimulala.