feat: add monitoring retention controls

go-backend/internal/monitoring/retention.go

@@ -0,0 +1,48 @@
+package monitoring
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+const (
+	ConfigMonitorRetentionDays  = "monitor_retention_days"
+	DefaultMonitorRetentionDays = 7
+	MinMonitorRetentionDays     = 1
+	MaxMonitorRetentionDays     = 3650
+)
+
+func MonitoringRetentionDaysFromConfigMap(cfg map[string]string) int {
+	if cfg == nil {
+		return DefaultMonitorRetentionDays
+	}
+	days, err := parseMonitoringRetentionDays(cfg[ConfigMonitorRetentionDays])
+	if err != nil {
+		return DefaultMonitorRetentionDays
+	}
+	return days
+}
+
+func NormalizeMonitoringRetentionDays(value string) (string, error) {
+	days, err := parseMonitoringRetentionDays(value)
+	if err != nil {
+		return "", err
+	}
+	return strconv.Itoa(days), nil
+}
+
+func parseMonitoringRetentionDays(value string) (int, error) {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return 0, fmt.Errorf("监控数据保留天数不能为空")
+	}
+	days, err := strconv.Atoi(trimmed)
+	if err != nil {
+		return 0, fmt.Errorf("监控数据保留天数必须是整数")
+	}
+	if days < MinMonitorRetentionDays || days > MaxMonitorRetentionDays {
+		return 0, fmt.Errorf("监控数据保留天数必须在 %d 到 %d 之间", MinMonitorRetentionDays, MaxMonitorRetentionDays)
+	}
+	return days, nil
+}

go-backend/internal/monitoring/retention_test.go

@@ -0,0 +1,40 @@
+package monitoring
+
+import "testing"
+
+func TestMonitoringRetentionDaysFromConfigMap(t *testing.T) {
+	tests := []struct {
+		name string
+		cfg  map[string]string
+		want int
+	}{
+		{"missing uses default", nil, 7},
+		{"valid custom", map[string]string{ConfigMonitorRetentionDays: "3"}, 3},
+		{"trimmed custom", map[string]string{ConfigMonitorRetentionDays: " 30 "}, 30},
+		{"invalid uses default", map[string]string{ConfigMonitorRetentionDays: "abc"}, 7},
+		{"too small uses default", map[string]string{ConfigMonitorRetentionDays: "0"}, 7},
+		{"too large uses default", map[string]string{ConfigMonitorRetentionDays: "3651"}, 7},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := MonitoringRetentionDaysFromConfigMap(tc.cfg); got != tc.want {
+				t.Fatalf("expected %d, got %d", tc.want, got)
+			}
+		})
+	}
+}
+
+func TestNormalizeMonitoringRetentionDays(t *testing.T) {
+	for _, value := range []string{"1", "7", "3650", " 30 "} {
+		if got, err := NormalizeMonitoringRetentionDays(value); err != nil || got == "" {
+			t.Fatalf("expected %q valid, got value=%q err=%v", value, got, err)
+		}
+	}
+
+	for _, value := range []string{"", "0", "-1", "3651", "abc", "1.5"} {
+		if got, err := NormalizeMonitoringRetentionDays(value); err == nil {
+			t.Fatalf("expected %q invalid, got value=%q", value, got)
+		}
+	}
+}