mscluster: add shared volumes collector and update documentation (#2301)

Signed-off-by: EisenbergD <dominik.eisenberg@beiersdorf.com>
Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>
Co-authored-by: EisenbergD <dominik.eisenberg@beiersdorf.com>
Co-authored-by: Jan-Otto Kröpke <mail@jkroepke.de>

internal/collector/mscluster/mscluster.go

@@ -38,6 +38,7 @@ const (
 	subCollectorNode          = "node"
 	subCollectorResource      = "resource"
 	subCollectorResourceGroup = "resourcegroup"
+	subCollectorSharedVolumes = "shared_volumes"
 )
 
 type Config struct {
@@ -52,6 +53,7 @@ var ConfigDefaults = Config{
 		subCollectorNode,
 		subCollectorResource,
 		subCollectorResourceGroup,
+		subCollectorSharedVolumes,
 	},
 }
 
@@ -62,6 +64,7 @@ type Collector struct {
 	collectorNode
 	collectorResource
 	collectorResourceGroup
+	collectorSharedVolumes
 
 	config    Config
 	miSession *mi.Session
@@ -156,6 +159,12 @@ func (c *Collector) Build(_ *slog.Logger, miSession *mi.Session) error {
 		}
 	}
 
+	if slices.Contains(c.config.CollectorsEnabled, subCollectorSharedVolumes) {
+		if err := c.buildSharedVolumes(); err != nil {
+			errs = append(errs, fmt.Errorf("failed to build shared_volumes collector: %w", err))
+		}
+	}
+
 	return errors.Join(errs...)
 }
 
@@ -166,10 +175,10 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 		return nil
 	}
 
-	errCh := make(chan error, 5)
+	errCh := make(chan error, 6)
 
 	wg := sync.WaitGroup{}
-	wg.Add(5)
+	wg.Add(6)
 
 	go func() {
 		defer wg.Done()
@@ -226,6 +235,16 @@ func (c *Collector) Collect(ch chan<- prometheus.Metric) error {
 		}()
 	}()
 
+	go func() {
+		defer wg.Done()
+
+		if slices.Contains(c.config.CollectorsEnabled, subCollectorSharedVolumes) {
+			if err := c.collectSharedVolumes(ch); err != nil {
+				errCh <- fmt.Errorf("failed to collect shared_volumes metrics: %w", err)
+			}
+		}
+	}()
+
 	wg.Wait()
 	close(errCh)
 

internal/collector/mscluster/mscluster_shared_volumes.go

@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: Apache-2.0
+//
+// Copyright The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build windows
+
+package mscluster
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/prometheus-community/windows_exporter/internal/mi"
+	"github.com/prometheus-community/windows_exporter/internal/types"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const nameSharedVolumes = Name + "_shared_volumes"
+
+type collectorSharedVolumes struct {
+	sharedVolumesMIQuery mi.Query
+
+	sharedVolumesInfo      *prometheus.Desc
+	sharedVolumesTotalSize *prometheus.Desc
+	sharedVolumesFreeSpace *prometheus.Desc
+}
+
+// msClusterDiskPartition represents the MSCluster_DiskPartition WMI class
+type msClusterDiskPartition struct {
+	Name       string `mi:"Name"`
+	Path       string `mi:"Path"`
+	TotalSize  uint64 `mi:"TotalSize"`
+	FreeSpace  uint64 `mi:"FreeSpace"`
+	Volume     string `mi:"VolumeLabel"`
+	VolumeGuid string `mi:"VolumeGuid"`
+}
+
+func (c *Collector) buildSharedVolumes() error {
+	sharedVolumesMIQuery, err := mi.NewQuery("SELECT Name, Path, TotalSize, FreeSpace, VolumeLabel, VolumeGuid FROM MSCluster_DiskPartition")
+	if err != nil {
+		return fmt.Errorf("failed to create WMI query: %w", err)
+	}
+
+	c.sharedVolumesMIQuery = sharedVolumesMIQuery
+
+	c.sharedVolumesInfo = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, nameSharedVolumes, "info"),
+		"Cluster Shared Volumes information (value is always 1)",
+		[]string{"name", "path", "volume_guid"},
+		nil,
+	)
+
+	c.sharedVolumesTotalSize = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, nameSharedVolumes, "total_bytes"),
+		"Total size of the Cluster Shared Volume in bytes",
+		[]string{"name", "volume_guid"},
+		nil,
+	)
+
+	c.sharedVolumesFreeSpace = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, nameSharedVolumes, "free_bytes"),
+		"Free space on the Cluster Shared Volume in bytes",
+		[]string{"name", "volume_guid"},
+		nil,
+	)
+
+	var dst []msClusterDiskPartition
+	if err := c.miSession.Query(&dst, mi.NamespaceRootMSCluster, c.sharedVolumesMIQuery); err != nil {
+		return fmt.Errorf("WMI query failed: %w", err)
+	}
+
+	return nil
+}
+
+func (c *Collector) collectSharedVolumes(ch chan<- prometheus.Metric) error {
+	var dst []msClusterDiskPartition
+	if err := c.miSession.Query(&dst, mi.NamespaceRootMSCluster, c.sharedVolumesMIQuery); err != nil {
+		return fmt.Errorf("WMI query failed: %w", err)
+	}
+
+	for _, partition := range dst {
+		volume := strings.TrimRight(partition.Volume, " ")
+
+		ch <- prometheus.MustNewConstMetric(
+			c.sharedVolumesInfo,
+			prometheus.GaugeValue,
+			1.0,
+			volume,
+			partition.Path,
+			partition.VolumeGuid,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.sharedVolumesTotalSize,
+			prometheus.GaugeValue,
+			float64(partition.TotalSize)*1024*1024, // Convert from KB to bytes
+			volume,
+			partition.VolumeGuid,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.sharedVolumesFreeSpace,
+			prometheus.GaugeValue,
+			float64(partition.FreeSpace)*1024*1024, // Convert from KB to bytes
+			volume,
+			partition.VolumeGuid,
+		)
+	}
+
+	return nil
+}