1 files changed, 160 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/cockroachdb/collect.go b/src/go/collectors/go.d.plugin/modules/cockroachdb/collect.go
new file mode 100644
index 000000000..0cdc2d1d8
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/modules/cockroachdb/collect.go
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package cockroachdb
+
+import (
+	"errors"
+
+	"github.com/netdata/netdata/go/go.d.plugin/pkg/prometheus"
+	"github.com/netdata/netdata/go/go.d.plugin/pkg/stm"
+)
+
+func validCockroachDBMetrics(scraped prometheus.Series) bool {
+	return scraped.FindByName("sql_restart_savepoint_count_internal").Len() > 0
+}
+
+func (c *CockroachDB) collect() (map[string]int64, error) {
+	scraped, err := c.prom.ScrapeSeries()
+	if err != nil {
+		return nil, err
+	}
+
+	if !validCockroachDBMetrics(scraped) {
+		return nil, errors.New("returned metrics aren't CockroachDB metrics")
+	}
+
+	mx := collectScraped(scraped, metrics)
+	calcUsableCapacity(mx)
+	calcUnusableCapacity(mx)
+	calcTotalCapacityUsedPercentage(mx)
+	calcUsableCapacityUsedPercentage(mx)
+	calcRocksDBCacheHitRate(mx)
+	calcActiveReplicas(mx)
+	calcCPUUsagePercent(mx)
+
+	return stm.ToMap(mx), nil
+}
+
+const precision = 1000
+
+func collectScraped(scraped prometheus.Series, metricList []string) map[string]float64 {
+	mx := make(map[string]float64)
+	for _, name := range metricList {
+		if ms := scraped.FindByName(name); ms.Len() == 1 {
+			if isMetricFloat(name) {
+				mx[name] = ms.Max() * precision
+			} else {
+				mx[name] = ms.Max()
+			}
+		}
+	}
+	return mx
+}
+
+func calcUsableCapacity(mx map[string]float64) {
+	if !hasAll(mx, metricCapacityAvailable, metricCapacityUsed) {
+		return
+	}
+	available := mx[metricCapacityAvailable]
+	used := mx[metricCapacityUsed]
+
+	mx[metricCapacityUsable] = available + used
+}
+
+func calcUnusableCapacity(mx map[string]float64) {
+	if !hasAll(mx, metricCapacity, metricCapacityAvailable, metricCapacityUsed) {
+		return
+	}
+	total := mx[metricCapacity]
+	available := mx[metricCapacityAvailable]
+	used := mx[metricCapacityUsed]
+
+	mx[metricCapacityUnusable] = total - (available + used)
+}
+
+func calcTotalCapacityUsedPercentage(mx map[string]float64) {
+	if !hasAll(mx, metricCapacity, metricCapacityUnusable, metricCapacityUsed) {
+		return
+	}
+	total := mx[metricCapacity]
+	unusable := mx[metricCapacityUnusable]
+	used := mx[metricCapacityUsed]
+
+	if mx[metricCapacity] == 0 {
+		mx[metricCapacityUsedPercentage] = 0
+	} else {
+		mx[metricCapacityUsedPercentage] = (unusable + used) / total * 100 * precision
+	}
+}
+
+func calcUsableCapacityUsedPercentage(mx map[string]float64) {
+	if !hasAll(mx, metricCapacityUsable, metricCapacityUsed) {
+		return
+	}
+	usable := mx[metricCapacityUsable]
+	used := mx[metricCapacityUsed]
+
+	if usable == 0 {
+		mx[metricCapacityUsableUsedPercentage] = 0
+	} else {
+		mx[metricCapacityUsableUsedPercentage] = used / usable * 100 * precision
+	}
+}
+
+func calcRocksDBCacheHitRate(mx map[string]float64) {
+	if !hasAll(mx, metricRocksDBBlockCacheHits, metricRocksDBBlockCacheMisses) {
+		return
+	}
+	hits := mx[metricRocksDBBlockCacheHits]
+	misses := mx[metricRocksDBBlockCacheMisses]
+
+	if sum := hits + misses; sum == 0 {
+		mx[metricRocksDBBlockCacheHitRate] = 0
+	} else {
+		mx[metricRocksDBBlockCacheHitRate] = hits / sum * 100 * precision
+	}
+}
+
+func calcActiveReplicas(mx map[string]float64) {
+	if !hasAll(mx, metricReplicasQuiescent) {
+		return
+	}
+	total := mx[metricReplicas]
+	quiescent := mx[metricReplicasQuiescent]
+
+	mx[metricReplicasActive] = total - quiescent
+}
+
+func calcCPUUsagePercent(mx map[string]float64) {
+	if hasAll(mx, metricSysCPUUserPercent) {
+		mx[metricSysCPUUserPercent] *= 100
+	}
+	if hasAll(mx, metricSysCPUSysPercent) {
+		mx[metricSysCPUSysPercent] *= 100
+	}
+	if hasAll(mx, metricSysCPUCombinedPercentNormalized) {
+		mx[metricSysCPUCombinedPercentNormalized] *= 100
+	}
+}
+
+func isMetricFloat(name string) bool {
+	// only Float metrics (see NewGaugeFloat64 in the cockroach repo):
+	// - GcPausePercent, CPUUserPercent, CPUCombinedPercentNorm, AverageQueriesPerSecond, AverageWritesPerSecond
+	switch name {
+	case metricSysCPUUserPercent,
+		metricSysCPUSysPercent,
+		metricSysCPUCombinedPercentNormalized,
+		metricRebalancingQueriesPerSecond,
+		metricRebalancingWritesPerSecond:
+		return true
+	}
+	return false
+}
+
+func hasAll(mx map[string]float64, key string, rest ...string) bool {
+	_, ok := mx[key]
+	if len(rest) == 0 {
+		return ok
+	}
+	return ok && hasAll(mx, rest[0], rest[1:]...)
+}