Remaining errors.Is for error equality checks

[redwrasse]

This PR follows up on #18510 to replace the rest of error equality/inequality checks with errors.Is, which is robust to error wrapping (https://pkg.go.dev/errors#pkg-overview).

Note I believe there are a number of cases of explicit error strings substring matching in tests for that are not covered in this PR. This PR just changes explicit err == and err != to errors.Is and !errors.Is.

@ivanvc

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: redwrasse
Once this PR has been reviewed and has the lgtm label, please assign wenjiaswe for approval. For more information see the Kubernetes Code Review Process.

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

Needs approval from an approver in each of these files:

• OWNERS

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

[k8s-ci-robot]

Hi @redwrasse. Thanks for your PR.

I'm waiting for a etcd-io member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

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.

[redwrasse]

@ivanvc let me know if you see any missing cases. this PR also builds on top of #18510, so we could also close that one and just work on this PR.

[redwrasse]

Seeing some package name conflicts, let me fix

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

Attention: Patch coverage is 61.70213% with 18 lines in your changes missing coverage. Please review.

Project coverage is 68.80%. Comparing base (4a11ca6) to head (799b315).
Report is 2 commits behind head on main.

❗ Current head 799b315 differs from pull request most recent head 1775d5e

Please upload reports for the commit 1775d5e to get more accurate results.

Files with missing lines	Patch %	Lines
server/etcdserver/api/v2discovery/discovery.go	0.00%	1 Missing and 1 partial ⚠️
server/etcdserver/api/v3discovery/discovery.go	0.00%	1 Missing and 1 partial ⚠️
server/etcdserver/api/v3rpc/watch.go	50.00%	1 Missing and 1 partial ⚠️
server/etcdserver/server.go	66.66%	2 Missing ⚠️
client/v3/client.go	66.66%	0 Missing and 1 partial ⚠️
client/v3/experimental/recipes/key.go	50.00%	1 Missing ⚠️
etcdctl/ctlv3/command/auth_command.go	0.00%	1 Missing ⚠️
pkg/proxy/server.go	50.00%	1 Missing ⚠️
server/etcdserver/api/rafthttp/snapshot_sender.go	0.00%	0 Missing and 1 partial ⚠️
server/etcdserver/api/v3rpc/lease.go	83.33%	0 Missing and 1 partial ⚠️
... and 4 more

❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

Files with missing lines	Coverage Δ
client/v3/watch.go	93.24% <100.00%> (-1.00%)	⬇️
server/etcdserver/api/rafthttp/pipeline.go	97.40% <100.00%> (ø)
server/etcdserver/api/rafthttp/stream.go	81.58% <100.00%> (-0.24%)	⬇️
server/etcdserver/api/v3compactor/periodic.go	90.24% <100.00%> (ø)
server/etcdserver/api/v3rpc/util.go	51.61% <100.00%> (ø)
server/lease/leasehttp/http.go	64.18% <100.00%> (+2.02%)	⬆️
client/v3/client.go	84.89% <66.66%> (ø)
client/v3/experimental/recipes/key.go	75.34% <50.00%> (ø)
etcdctl/ctlv3/command/auth_command.go	0.00% <0.00%> (ø)
pkg/proxy/server.go	60.95% <50.00%> (+0.67%)	⬆️
... and 10 more

... and 19 files with indirect coverage changes

@@            Coverage Diff             @@
##             main   #18551      +/-   ##
==========================================
+ Coverage   68.73%   68.80%   +0.07%     
==========================================
  Files         420      420              
  Lines       35470    35470              
==========================================
+ Hits        24381    24406      +25     
+ Misses       9668     9647      -21     
+ Partials     1421     1417       -4     

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 4a11ca6...1775d5e. Read the comment docs.

[henrybear327]

/ok-to-test

[redwrasse]

goimports error, i'll fix it

[k8s-ci-robot]

@redwrasse: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-etcd-unit-test-386	1775d5e	link	true	/test pull-etcd-unit-test-386
pull-etcd-integration-1-cpu-amd64	1775d5e	link	true	/test pull-etcd-integration-1-cpu-amd64

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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. I understand the commands that are listed here.

[ivanvc]

Hi @redwrasse, thanks for the pull request. Due to its size and ease of review, would you be able to help us break it into multiple smaller PRs? I suggest one per module, i.e., client, contrib, etcdctl, etc...

I also suggest waiting for #18510 to be merged so you can continue working on it after we have the maintainers' approval and get it merged into main.

Thanks again, Samir.

[ivanvc]

Link to #18576

[redwrasse]

@ivanvc sounds good, I'll hold off for now and if we move forward I can help with a separate PR per-module.

[ivanvc]

@redwrasse, is it okay to assign you to our new parent issue for this? (#18576) If that's ok, you can comment /assign on that issue, and k8s-bot will assign it to you.