server: Simplify passing logger setup by passing only logger

[serathius]

Follow up from #12326
cc @ptabor

[codecov-commenter]

Codecov Report

Merging #12968 (41ed748) into main (7ba53c7) will increase coverage by 5.02%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##             main   #12968      +/-   ##
==========================================
+ Coverage   62.73%   67.76%   +5.02%     
==========================================
  Files         417      404      -13     
  Lines       33332    32750     -582     
==========================================
+ Hits        20910    22192    +1282     
+ Misses      10338     8584    -1754     
+ Partials     2084     1974     -110     

Flag	Coverage Δ
all	67.76% <83.33%> (+5.02%)	⬆️

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

Impacted Files	Coverage Δ
server/config/config.go	74.24% <ø> (+34.84%)	⬆️
server/embed/config.go	70.52% <ø> (+24.83%)	⬆️
server/embed/etcd.go	69.13% <ø> (+3.00%)	⬆️
server/embed/config_logging.go	75.53% <66.66%> (+26.21%)	⬆️
server/etcdserver/raft.go	87.20% <100.00%> (+6.11%)	⬆️
raft/quorum/quorum.go	0.00% <0.00%> (-100.00%)	⬇️
raft/tracker/state.go	0.00% <0.00%> (-100.00%)	⬇️
...ver/proxy/grpcproxy/adapter/lock_client_adapter.go	0.00% <0.00%> (-100.00%)	⬇️
client/v3/namespace/lease.go	0.00% <0.00%> (-69.24%)	⬇️
server/proxy/grpcproxy/election.go	6.25% <0.00%> (-68.75%)	⬇️
... and 205 more

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[lilic]

Nice!

Curious should we mention this in the release notes, as its an exposed server configuration, or what do we consider as public API breaking changes?

[ptabor]

I think that exported properties of the 'embed' package has not changed, so its an internal change.

[gyuho]

I think that exported properties of the 'embed' package has not changed, so its an internal change.

If we are going to ignore the logging fields from embed.Config, can we highlight these in CHANGELOG and maybe remove those fields in 3.6?

[ptabor]

embed.Config never accepted loggerCore & loggerConfig publicly:

etcd/server/embed/config.go

Lines 381 to 383 in ddc4f47

	loggerCore zapcore.Core
	loggerWriteSyncer zapcore.WriteSyncer

The way to configure it was to pass:

etcd/server/embed/config.go

Line 368 in ddc4f47

ZapLoggerBuilder func(*Config) error

So the breaking change already happened in: eafbc8c where the signature got simplified.
Will provide small PR that brings back the compatiblity.

[ptabor]

Brought back the original API (and changelog in #12973)