Motivation is as follows:
- etcdctl we only depend on clientv3 APIs, no dependencies of bolt, backend, mvcc, file-layout
- etcdctl can be officially supported across wide range of versions, while etcdutl is pretty specific to file format at particular version.
it's step towards desired modules layout, documented in: https://etcd.io/docs/next/dev-internal/modules/
clientv3 logs (especially tests) were poluted with unattributed to testing.T log lines:
```
{"level":"warn","ts":"2021-04-29T12:42:11.055+0200","logger":"etcd-client","caller":"v3/retry_interceptor.go:64","msg":"retrying of unary invoker failed","target":"etcd-endpoints://0xc0000fafc0/#initially=[unix://localhost:m10]","attempt":0,"error":"rpc error: code = ResourceExhausted desc = etcdserver: mvcc: database space exceeded"}
```
The reasons were 2 fold:
- Interceptors were copying logger before "WithLogger" could modify it.
- We were not propagating the loggers in a few testing contexts.
ClusterVersionSet, ClusterMemberAttrSet, DowngradeInfoSet functions are
writing both to V2store and backend. Prior this CL there were
in a branch not executed if shouldApplyV3 was false,
e.g. during restore when Backend is up-to-date (has high
consistency-index) while v2store requires replay from WAL log.
The most serious consequence of this bug was that v2store after restore
could have different index (revision) than the same exact store before restore,
so potentially different content between replicas.
Also this change is supressing double-applying of Membership
(ClusterConfig) changes on Backend (store v3) - that lackilly are not
part of MVCC/KeyValue store, so they didn't caused Revisions to be
bumped.
Inspired by jingyih@ comment:
https://github.com/etcd-io/etcd/pull/12820#issuecomment-815299406
We make v2 client code a module go.etcd.io/etcd/client/v2.
Pretty mechanical change that can be summarized as:
mkdir client/v2
cd client/v2 && git mod init go.etcd.io/etcd/client/v2
git mv client/*.go client/v2/
find -name '*.go' | xargs sed -i --follow-symlinks 's|/v3/client["]|/client/v2\"|g'
+ fixing changelog, bom, go.mod etc.
"snapshot" Restore/Status code was the only remaining dependency of client on 'server'
code. The code is solelly used by etcdctl. Long-term the snapshot code
should be migrated to 'etcdadm' style of tool such that we can
distinguish tool solelly depending on networking API vs. tools that
operation on etcd files directly.
We left snapshot.Save() code in clientv3.snapshot package, such that
clients can benefits from automated download&safe to file snapshot
functionality over the wire.
This CL fixes:
COVERDIR=./coverage PASSES="build_cov" && go test --tags cov -v ./tests/e2e
and is part of the effort to make:
COVERDIR=coverage PASSES="build_cov cov" ./test
fully pass.
The args passed to ./bin/etcd_test and ./bin/etcdctl_test binaries were
mismatched. The protocol of passing the arguments using
environment variables has been replaces with proper passing of flags.
How the measurement of coverage by e2e tests works:
1. COVERDIR=./coverage PASSES="build_cov" are generating
./bin/etcd_test and ./bin/etcdctl_test binaries.
2. These binaries are tests (as coverage can be computed only for
tests) [see ./main_test.go ./etcdctl/main_test.go], but this tests are
running the main logic of the server and uppon termination (or SIGTERM
signal) are writting proper .coverprofile files in the $COVERDIR folder.
The binaries used to take arguments using env variables, but its not
needed any longer. The binaries can consume any command line arguments
that either test (so --test.fooo) or the original binary can consume.
3. The tests/e2e (when compiled with the --tags cov) are starting the
_test binaries instead of the original binaries, such that the coverage
is being collected.
This change makes the etcd package compatible with the existing Go
ecosystem for module versioning.
Used this tool to update package imports:
https://github.com/KSubedi/gomove
This changes have started at etcdctl under auth.go, and make changes to stub out everything down into the internal raft. Made changes to the .proto files and regenerated them so that the local version would build successfully.
