修复代理与日志链路的可靠性问题

db/clickhouse_test.go

@@ -214,6 +214,26 @@ func TestClosePreventsConcurrentConnectFromPublishing(t *testing.T) {
 	}
 }
 
+func TestOldGenerationCannotMarkReplacementUnhealthy(t *testing.T) {
+	pool := &Pool{conn: newFakeClickHouseConn(), healthy: true, generation: 1}
+	oldGeneration := pool.Generation()
+
+	pool.mu.Lock()
+	pool.conn = newFakeClickHouseConn()
+	pool.generation++
+	pool.healthy = true
+	pool.mu.Unlock()
+
+	pool.MarkUnhealthyGeneration(oldGeneration)
+	if !pool.Healthy() {
+		t.Fatal("old connection failure marked replacement connection unhealthy")
+	}
+	pool.MarkUnhealthyGeneration(pool.Generation())
+	if pool.Healthy() {
+		t.Fatal("current connection failure did not mark pool unhealthy")
+	}
+}
+
 func assertNonDestructiveMigration(t *testing.T, statements []string) {
 	t.Helper()
 	if len(statements) == 0 || !strings.Contains(strings.ToUpper(statements[0]), "CREATE TABLE IF NOT EXISTS") {