// server lists all metrics that could be returned for the requested path.
//
// The (repeatable) `buckets` query parameter is a list of bucket names (or it
// could be a comma separated value) to return metrics with a bucket label.
// Bucket metrics will be returned only for the provided buckets. If no buckets
// parameter is provided, no bucket metrics are returned.

		}
		return nil
	}
}

// MetricsGroup - represents a group of metrics. It includes a `MetricsLoaderFn`
// function that provides a way to load the metrics from the system. The metrics
// are cached and refreshed after a given timeout.
//
// For metrics with a `bucket` dimension, a list of buckets argument is required
// to collect the metrics.
//
// It implements the prometheus.Collector interface for metric groups without a

	// Queued operations
	Queued InQueueMetric `json:"queued"`
	// Proxy stats
	Proxied ProxyMetric `json:"proxied"`
	// replication metrics summary for each site replication peer
	Metrics map[string]SRMetric `json:"replMetrics"`
	// uptime of node being queried for site replication metrics
	Uptime int64 `json:"uptime"`

)

// loadAPIRequestsHTTPMetrics - reads S3 HTTP metrics.
//
// This is a `MetricsLoaderFn`.
//
// This includes node level S3 HTTP metrics.
//
// This function currently ignores `opts`.
func loadAPIRequestsHTTPMetrics(ctx context.Context, m MetricValues, _ *metricsCache) error {
	// Collect node level S3 HTTP metrics.
	httpStats := globalHTTPStats.toServerHTTPStats(false)

type InQueueStats struct {
	nowBytes   int64 `json:"-"`
	nowCount   int64 `json:"-"`
	histCounts metrics.Histogram
	histBytes  metrics.Histogram
}

func newInQueueStats(r metrics.Registry, lbl string) InQueueStats {
	histCounts := metrics.NewHistogram(metrics.NewUniformSample(100))
	histBytes := metrics.NewHistogram(metrics.NewUniformSample(100))

	r.Register("replication.queue.counts."+lbl, histCounts)

		"Count of online drives in the cluster")
	healthDrivesCountMD = NewGaugeMD(healthDrivesCount,
		"Count of all drives in the cluster")
)

// loadClusterHealthDriveMetrics - `MetricsLoaderFn` for cluster storage drive metrics
// such as online, offline and total drives.
func loadClusterHealthDriveMetrics(ctx context.Context, m MetricValues,
	c *metricsCache,
) error {
	clusterDriveMetrics, _ := c.clusterDriveMetrics.Get()

	usageVersionCountDistribution = "version_count_distribution"
)

var (
	usageSinceLastUpdateSecondsMD = NewGaugeMD(usageSinceLastUpdateSeconds,
		"Time since last update of usage metrics in seconds")
	usageTotalBytesMD = NewGaugeMD(usageTotalBytes,
		"Total cluster usage in bytes")
	usageObjectsCountMD = NewGaugeMD(usageObjectsCount,
		"Total cluster objects count")

	ilmVersionsScannedMD                = NewCounterMD(versionsScanned, "Total number of object versions checked for ILM actions since server start")
)

// loadILMMetrics - `MetricsLoaderFn` for ILM metrics.
func loadILMMetrics(_ context.Context, m MetricValues, _ *metricsCache) error {
	if globalExpiryState != nil {
		m.Set(expiryPendingTasks, float64(globalExpiryState.PendingTasks()))
	}
	if globalTransitionState != nil {

)

// loadClusterIAMMetrics - `MetricsLoaderFn` for cluster IAM metrics.
func loadClusterIAMMetrics(_ context.Context, m MetricValues, _ *metricsCache) error {
	m.Set(lastSyncDurationMillis, float64(atomic.LoadUint64(&globalIAMSys.LastRefreshDurationMilliseconds)))
	pluginAuthNMetrics := globalAuthNPlugin.Metrics()
	m.Set(pluginAuthnServiceFailedRequestsMinute, float64(pluginAuthNMetrics.FailedRequests))

)

// loadClusterNotificationMetrics - `MetricsLoaderFn` for cluster notification metrics.
func loadClusterNotificationMetrics(_ context.Context, m MetricValues, _ *metricsCache) error {
	if globalEventNotifier == nil {
		return nil
	}

	nstats := globalEventNotifier.targetList.Stats()