Save bootstrap trace events in a circular buffer (#16823)

cmd/bootstrap-messages_test.go

@@ -0,0 +1,60 @@
+// Copyright (c) 2015-2023 MinIO, Inc.
+//
+// This file is part of MinIO Object Storage stack
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package cmd
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestBootstrap(t *testing.T) {
+	// Bootstrap events exceed bootstrap messages limit
+	bsTracer := &bootstrapTracer{}
+	for i := 0; i < bootstrapMsgsLimit+10; i++ {
+		bsTracer.Record(fmt.Sprintf("msg-%d", i))
+	}
+
+	traceInfos := bsTracer.Events()
+	if len(traceInfos) != bootstrapMsgsLimit {
+		t.Fatalf("Expected length of events %d but got %d", bootstrapMsgsLimit, len(traceInfos))
+	}
+
+	// Simulate the case where bootstrap events were updated a day ago
+	bsTracer.lastUpdate = time.Now().UTC().Add(-25 * time.Hour)
+	bsTracer.DropEvents()
+	if !bsTracer.Empty() {
+		t.Fatalf("Expected all bootstrap events to have been dropped, but found %d events", len(bsTracer.Events()))
+	}
+
+	// Fewer than 4K bootstrap events
+	for i := 0; i < 10; i++ {
+		bsTracer.Record(fmt.Sprintf("msg-%d", i))
+	}
+	events := bsTracer.Events()
+	if len(events) != 10 {
+		t.Fatalf("Expected length of events %d but got %d", 10, len(events))
+	}
+	for i, traceInfo := range bsTracer.Events() {
+		msg := fmt.Sprintf("msg-%d", i)
+		if !strings.HasSuffix(traceInfo.Message, msg) {
+			t.Fatalf("Expected %s but got %s", msg, traceInfo.Message)
+		}
+	}
+}