Use atomic.Bool for OnFlushEnd callback test (#827)

The OnFlushStart/OnFlushEnd context-propagation check used a plain
bool. On Windows the flush can complete within a single clock tick, so
use atomic.Bool to avoid a data race flagged by CI.

Bump cluster.wait-ready sleep from 2s to 3s to reduce false negatives
on slower CI runners.

Signed-off-by: Sean Chittenden <sean.chittenden@crowdstrike.com>

Author: sean-

CHANGELOG.md

@@ -157,7 +157,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ### Fixed
 
-- Fix bulk indexer HTML-escaping `_id` and `routing` values containing `<`, `>`, or `&` characters, causing OpenSearch to store escaped values (e.g., `\u003croot_account\u003e` stored instead of `<root_account>`), leading to duplicate documents, unreachable data on read-by-ID paths, and potential shard routing mismatches. Present since the `json.Marshal` migration in 2021 (commit `3da59092`). Replace `json.Marshal` with `json.NewEncoder` + `SetEscapeHTML(false)` in `opensearchutil.worker.writeMeta` and `opensearchutil.JSONReader`; replace per-worker `aux []byte` with `sync.Pool`-backed `*bytes.Buffer`; add table-driven test coverage for `writeMeta` edge cases ([#824](https://github.com/opensearch-project/opensearch-go/pull/824))
+- Fix bulk indexer HTML-escaping `_id` and `routing` values containing `<`, `>`, or `&` characters, causing OpenSearch to store escaped values (e.g., `\u003croot_account\u003e` stored instead of `<root_account>`), leading to duplicate documents, unreachable data on read-by-ID paths, and potential shard routing mismatches. Present since the `json.Marshal` migration in 2021 (commit `3da59092`). Replace `json.Marshal` with `json.NewEncoder` + `SetEscapeHTML(false)` in `opensearchutil.worker.writeMeta` and `opensearchutil.JSONReader`; replace per-worker `aux []byte` with `sync.Pool`-backed `*bytes.Buffer`; add table-driven test coverage for `writeMeta` edge cases and refactor remaining `TestBulkIndexer` subtests to table-driven `require`-based style ([#824](https://github.com/opensearch-project/opensearch-go/pull/824))
 - Fix pool replacement orphaning resurrection goroutines during node discovery, causing connections to become permanently dead with no active health checker ([#786](https://github.com/opensearch-project/opensearch-go/pull/786))
 - Extract `newMultiServerPoolFromClientWithLock` as single source of truth for Client-to-pool settings propagation ([#786](https://github.com/opensearch-project/opensearch-go/pull/786))
 - Fix discovery pool wipe when all cluster nodes time out during `/_nodes/http` fan-out: parse `_nodes` metadata envelope and return `errDiscoveryEmpty` when `successful == 0`, preserving the existing connection pool for retry ([#821](https://github.com/opensearch-project/opensearch-go/pull/821))

Makefile

@@ -437,7 +437,7 @@ cluster.wait-ready: ## Poll cluster until health status is green or yellow
 				else \
 					printf "\033[33m⋯ Waiting for cluster to respond (attempt $$ATTEMPT/$$MAX_ATTEMPTS)\033[0m\n"; \
 					ATTEMPT=$$((ATTEMPT + 1)); \
-					sleep 2; \
+					sleep 3; \
 					continue; \
 				fi; \
 			fi; \
@@ -464,7 +464,7 @@ cluster.wait-ready: ## Poll cluster until health status is green or yellow
 				printf "\033[33m⋯ Waiting for cluster to respond (attempt $$ATTEMPT/$$MAX_ATTEMPTS)\033[0m\n"; \
 			fi; \
 			ATTEMPT=$$((ATTEMPT + 1)); \
-			sleep 2; \
+			sleep 3; \
 		done; \
 		printf "\033[31m✗ Cluster failed to become ready after $$MAX_ATTEMPTS attempts\033[0m\n"; \
 		printf "\033[2m\n--- Diagnostic Information ---\033[0m\n"; \

opensearchutil/bulk_indexer_internal_test.go

@@ -708,7 +708,7 @@ func TestBulkIndexerCallbacks(t *testing.T) {
 				}}})
 				flushIndex := testutil.MustUniqueString(t, "test-flush")
 
-				var flushEndCalled bool
+				var flushEndCalled atomic.Bool
 				bi, _ := NewBulkIndexer(BulkIndexerConfig{
 					Client: client,
 					Index:  flushIndex,
@@ -717,7 +717,7 @@ func TestBulkIndexerCallbacks(t *testing.T) {
 					},
 					OnFlushEnd: func(ctx context.Context) {
 						if v, ok := ctx.Value(contextKey("flushing")).(bool); ok && v {
-							flushEndCalled = true
+							flushEndCalled.Store(true)
 						}
 					},
 				})
@@ -729,7 +729,7 @@ func TestBulkIndexerCallbacks(t *testing.T) {
 				require.NoError(t, bi.Close(context.Background()))
 
 				require.Equal(t, uint64(1), bi.Stats().NumAdded, "NumAdded")
-				require.True(t, flushEndCalled, "OnFlushEnd should have been called with the context from OnFlushStart")
+				require.True(t, flushEndCalled.Load(), "OnFlushEnd should have been called with the context from OnFlushStart")
 			},
 		},
 		{