Fix cluster peer HTTP SRV discovery when no HTTPS records exist

[brandond]

embed: Fix cluster peer HTTP SRV discovery

Fixed issue where peer SRV discovery failed if no HTTPS endpoints were discovered. HTTP endpoints were never added to the address list due to a bad error check, and the _etcd-server-ssl._tcp.<domain> failure masked the subsequent success of lookups for _etcd-server._tcp.<domain>

Fixes #11321

[codecov-io]

Codecov Report

Merging #11776 into master will decrease coverage by 0.28%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master   #11776      +/-   ##
==========================================
- Coverage   66.65%   66.36%   -0.29%     
==========================================
  Files         403      403              
  Lines       36881    36881              
==========================================
- Hits        24582    24477     -105     
- Misses      10811    10906      +95     
- Partials     1488     1498      +10     

Impacted Files	Coverage Δ
embed/config.go	54.12% <0.00%> (ø)
auth/store.go	58.84% <0.00%> (-19.53%)	⬇️
pkg/netutil/netutil.go	61.47% <0.00%> (-7.38%)	⬇️
clientv3/namespace/watch.go	87.87% <0.00%> (-6.07%)	⬇️
etcdserver/api/v3rpc/lease.go	77.21% <0.00%> (-5.07%)	⬇️
proxy/grpcproxy/watcher.go	89.79% <0.00%> (-4.09%)	⬇️
clientv3/leasing/cache.go	87.77% <0.00%> (-3.89%)	⬇️
pkg/testutil/recorder.go	77.77% <0.00%> (-3.71%)	⬇️
etcdserver/util.go	95.23% <0.00%> (-3.58%)	⬇️
clientv3/leasing/txn.go	88.09% <0.00%> (-3.18%)	⬇️
... and 18 more

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[xorjain]

Thanks a lot for this fix @brandond .

Can someone from the team please merge this change? Thanks in advance.

[der-eismann]

Yeah, we also really need this PR merged so we can finally upgrade our cluster.

[brandond]

Is there anything I can do to help move this forward? I realize pulling in multierr might be controversial, I'm open to alternate approaches to wrapping or combining the errors.

[trivigy]

@brandond have you been able to find a workaround in the meantime? Or did you endup just using your own fork?

[brandond]

@trivigy yeah I'm just running off a local fork.

[der-eismann]

@gyuho could you (or another maintainer) maybe have a look? We finally want to upgrade.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed after 21 days if no further activity occurs. Thank you for your contributions.

[der-eismann]

Not stale

[ptabor]

I'm sorry for not looking at this earlier. Thank you for the fix.

Could you, please:

• Rebase this
• Add a regression test for this scenario.

[brandond]

Rebased and requested changes made. I'll take a look at how to best mock the SRV responses for a proper test.

[ptabor]

Thank you for the iteration.

• Please run ./script/fix.sh, as go.mod -> go.sum went out of sync, and that's the reason why the test fails.
• Is it possible to add a regression test for this scenario ?

[brandond]

@ptabor go.sum should be fixed now. I added some tests for both sections of the codebase that I touched; hopefully that looks good? I'm not sure how to get codecov to update.

[ptabor]

Thank you for fix.
Don't worry about code cov.
[edit: In ~30min there should be link at the end of this test output: https://travis-ci.com/github/etcd-io/etcd/jobs/479950649]

Hopefully last thing to update: There is inconsistency in go.mod's that break PASSES="fmt" ./test.sh

FAIL: inconsistent versions for depencency: go.uber.org/multierr
  - go.uber.org/multierr@v1.5.0 from: go.etcd.io/etcd/client/v3
  - go.uber.org/multierr@v1.6.0 from: go.etcd.io/etcd/server/v3
FAIL: inconsistent dependencies

[brandond]

I have no idea where any of that is coming from, the only go.mod that references multierr is in server. I'm going to see if squashing my changes and then doing a clean set of go.mod changes fixes this.

[brandond]

Well I fixed that but now CodeQL appears to be failing due to some transient github error?

[ptabor]

Thank you !