Fix replication tests

[tristaZero]

• If this pull request closes/resolves/fixes an existing issue, replace the issue number. Fixes [BYDB-Replica] Add integration test for BanyanDB replication resilience skywalking#13229.
• Update the CHANGES log.

[Copilot]

Pull request overview

This PR adds a replication integration test suite to verify that the BanyanDB cluster can survive node failures when data is replicated across multiple nodes. The test creates a cluster with 3 data nodes and a replication factor of 2, then simulates a node failure and verifies data is still accessible.

Key Changes:

• Adds new replication test suite with setup for a 3-node cluster with replication factor of 2
• Introduces entity_replicated test case to verify query functionality after node failure
• Creates replicated_group configuration with replicas: 2 setting

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
test/integration/replication/replication_test.go	Main test file that verifies cluster survives node failure and data remains accessible
test/integration/replication/replication_suite_test.go	Test suite setup with 3 data nodes, etcd server, and schema preloading
test/cases/measure/data/want/entity_replicated.yaml	Expected query results for the replicated data test case
test/cases/measure/data/input/entity_replicated.yaml	Query specification for testing replicated measure data
test/cases/measure/data/input/entity_replicated.ql	Query language definition for the replicated data test
test/cases/init.go	Adds data initialization for service_traffic in replicated_group
pkg/test/measure/testdata/measures/service_traffic_replicated.json	Measure schema definition for service_traffic in replicated_group
pkg/test/measure/testdata/groups/replicated.json	Group configuration with replicas=2 for replication testing
CHANGES.md	Documents addition of replication integration test

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[Copilot]

The dataNodeClosers variable is accessed in the test but is not properly shared across test processes. In Ginkgo's SynchronizedBeforeSuite, the first function runs once on process 1 and returns serialized data to other processes via the second function. Package-level variables set in the first function are not accessible in tests running in other processes.

The dataNodeClosers slice should be serialized and passed through the suite configuration (like liaisonAddr, etcdEndpoint, and now), but since closers are functions that cannot be serialized, the test architecture needs to be reconsidered.

One solution is to avoid stopping nodes in parallel tests, or ensure this specific test doesn't run in parallel mode. Another approach is to store node information (like node IDs) instead of closers and implement a shutdown mechanism through the test framework.

[Copilot]

The cleanup logic in deferFunc will attempt to close data nodes that may have already been stopped during test execution (line 83-84 in replication_test.go). When a test calls dataNodeClosers[0]() and then removes it from the slice, the deferFunc will still iterate over the remaining closers, but if tests fail or multiple tests run, this could lead to attempting to close already-closed nodes or missing nodes that should be closed.

Consider implementing idempotent close operations or tracking which nodes have been closed to avoid double-closure issues. Additionally, ensure that node closures in tests don't interfere with the cleanup process.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 46.25%. Comparing base (3530dd9) to head (555aaf2).
⚠️ Report is 91 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #893      +/-   ##
==========================================
+ Coverage   45.97%   46.25%   +0.27%     
==========================================
  Files         328      367      +39     
  Lines       55505    56483     +978     
==========================================
+ Hits        25520    26124     +604     
+ Misses      27909    27854      -55     
- Partials     2076     2505     +429     

Flag	Coverage Δ
banyand	49.52% <ø> (?)
bydbctl	81.91% <ø> (?)
fodc	90.65% <ø> (?)
pkg	29.08% <ø> (?)

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated no new comments.

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