1 files changed, 205 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/modules/consul/collect_metrics.go b/src/go/collectors/go.d.plugin/modules/consul/collect_metrics.go
new file mode 100644
index 000000000..8dcfe1838
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/modules/consul/collect_metrics.go
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package consul
+
+import (
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+
+	"github.com/netdata/netdata/go/go.d.plugin/pkg/prometheus"
+)
+
+func (c *Consul) collectMetricsPrometheus(mx map[string]int64) error {
+	mfs, err := c.prom.Scrape()
+	if err != nil {
+		return err
+	}
+
+	// Key Metrics (https://developer.hashicorp.com/consul/docs/agent/telemetry#key-metrics)
+
+	// prometheus metrics are messy:
+	// - if 'disable_hostname' is false (default):
+	//   - consul_autopilot_failure_tolerance => consul_hostname_autopilot_failure_tolerance
+	//   - both are exposed
+	//   - only the one with the hostname has the correct value
+	// - 1.14.3 (it probably has something to do with cloud management version):
+	//   - runtime_sys_bytes => runtime_sys_bytes_sys_bytes; consul_autopilot_healthy => consul_autopilot_healthy_healthy
+	//   - both are exposed
+	//   - only the one with the double name has the correct value
+
+	if c.isServer() {
+		c.collectSummary(mx, mfs, "raft_thread_main_saturation")
+		c.collectSummary(mx, mfs, "raft_thread_fsm_saturation")
+		c.collectSummary(mx, mfs, "raft_boltdb_logsPerBatch")
+		c.collectSummary(mx, mfs, "kvs_apply")
+		c.collectSummary(mx, mfs, "txn_apply")
+		c.collectSummary(mx, mfs, "raft_boltdb_storeLogs")
+		c.collectSummary(mx, mfs, "raft_rpc_installSnapshot") // make sense for followers only
+		c.collectSummary(mx, mfs, "raft_commitTime")          // make sense for leader only
+		c.collectSummary(mx, mfs, "raft_leader_lastContact")  // make sense for leader only
+
+		c.collectCounter(mx, mfs, "raft_apply", precision) // make sense for leader only
+		c.collectCounter(mx, mfs, "raft_state_candidate", 1)
+		c.collectCounter(mx, mfs, "raft_state_leader", 1)
+
+		c.collectGaugeBool(mx, mfs, "autopilot_healthy", "autopilot_healthy_healthy")
+		c.collectGaugeBool(mx, mfs, "server_isLeader", "server_isLeader_isLeader")
+		c.collectGauge(mx, mfs, "autopilot_failure_tolerance", 1, "autopilot_failure_tolerance_failure_tolerance")
+		c.collectGauge(mx, mfs, "raft_fsm_lastRestoreDuration", 1)
+		c.collectGauge(mx, mfs, "raft_leader_oldestLogAge", 1, "raft_leader_oldestLogAge_oldestLogAge")
+		c.collectGauge(mx, mfs, "raft_boltdb_freelistBytes", 1, "raft_boltdb_freelistBytes_freelistBytes")
+
+		if isLeader, ok := c.isLeader(mfs); ok {
+			if isLeader && !c.hasLeaderCharts {
+				c.addLeaderCharts()
+				c.hasLeaderCharts = true
+			}
+			if !isLeader && c.hasLeaderCharts {
+				c.removeLeaderCharts()
+				c.hasLeaderCharts = false
+			}
+			if !isLeader && !c.hasFollowerCharts {
+				c.addFollowerCharts()
+				c.hasFollowerCharts = true
+			}
+			if isLeader && c.hasFollowerCharts {
+				c.removeFollowerCharts()
+				c.hasFollowerCharts = false
+			}
+		}
+	}
+
+	c.collectGauge(mx, mfs, "system_licenseExpiration", 3600, "system_licenseExpiration_licenseExpiration")
+
+	c.collectCounter(mx, mfs, "client_rpc", 1)
+	c.collectCounter(mx, mfs, "client_rpc_exceeded", 1)
+	c.collectCounter(mx, mfs, "client_rpc_failed", 1)
+
+	c.collectGauge(mx, mfs, "runtime_alloc_bytes", 1, "runtime_alloc_bytes_alloc_bytes")
+	c.collectGauge(mx, mfs, "runtime_sys_bytes", 1, "runtime_sys_bytes_sys_bytes")
+	c.collectGauge(mx, mfs, "runtime_total_gc_pause_ns", 1, "runtime_total_gc_pause_ns_total_gc_pause_ns")
+
+	return nil
+}
+
+func (c *Consul) isLeader(mfs prometheus.MetricFamilies) (bool, bool) {
+	var mf *prometheus.MetricFamily
+	for _, v := range []string{"server_isLeader_isLeader", "server_isLeader"} {
+		if mf = mfs.GetGauge(c.promMetricNameWithHostname(v)); mf != nil {
+			break
+		}
+		if mf = mfs.GetGauge(c.promMetricName(v)); mf != nil {
+			break
+		}
+	}
+
+	if mf == nil {
+		return false, false
+	}
+
+	return mf.Metrics()[0].Gauge().Value() == 1, true
+}
+
+func (c *Consul) collectGauge(mx map[string]int64, mfs prometheus.MetricFamilies, name string, mul float64, aliases ...string) {
+	var mf *prometheus.MetricFamily
+	for _, v := range append(aliases, name) {
+		if mf = mfs.GetGauge(c.promMetricNameWithHostname(v)); mf != nil {
+			break
+		}
+		if mf = mfs.GetGauge(c.promMetricName(v)); mf != nil {
+			break
+		}
+	}
+
+	if mf == nil {
+		return
+	}
+
+	v := mf.Metrics()[0].Gauge().Value()
+
+	if !math.IsNaN(v) {
+		mx[name] = int64(v * mul)
+	}
+}
+
+func (c *Consul) collectGaugeBool(mx map[string]int64, mfs prometheus.MetricFamilies, name string, aliases ...string) {
+	var mf *prometheus.MetricFamily
+	for _, v := range append(aliases, name) {
+		if mf = mfs.GetGauge(c.promMetricNameWithHostname(v)); mf != nil {
+			break
+		}
+		if mf = mfs.GetGauge(c.promMetricName(v)); mf != nil {
+			break
+		}
+	}
+
+	if mf == nil {
+		return
+	}
+
+	v := mf.Metrics()[0].Gauge().Value()
+
+	if !math.IsNaN(v) {
+		mx[name+"_yes"] = boolToInt(v == 1)
+		mx[name+"_no"] = boolToInt(v == 0)
+	}
+}
+
+func (c *Consul) collectCounter(mx map[string]int64, mfs prometheus.MetricFamilies, name string, mul float64) {
+	mf := mfs.GetCounter(c.promMetricName(name))
+	if mf == nil {
+		return
+	}
+
+	v := mf.Metrics()[0].Counter().Value()
+
+	if !math.IsNaN(v) {
+		mx[name] = int64(v * mul)
+	}
+}
+
+func (c *Consul) collectSummary(mx map[string]int64, mfs prometheus.MetricFamilies, name string) {
+	mf := mfs.GetSummary(c.promMetricName(name))
+	if mf == nil {
+		return
+	}
+
+	m := mf.Metrics()[0]
+
+	for _, q := range m.Summary().Quantiles() {
+		v := q.Value()
+		// MaxAge is 10 seconds (hardcoded)
+		// https://github.com/hashicorp/go-metrics/blob/b6d5c860c07ef6eeec89f4a662c7b452dd4d0c93/prometheus/prometheus.go#L227
+		if math.IsNaN(v) {
+			v = 0
+		}
+
+		id := fmt.Sprintf("%s_quantile=%s", name, formatFloat(q.Quantile()))
+		mx[id] = int64(v * precision * precision)
+	}
+
+	mx[name+"_sum"] = int64(m.Summary().Sum() * precision)
+	mx[name+"_count"] = int64(m.Summary().Count())
+}
+
+func (c *Consul) promMetricName(name string) string {
+	px := c.cfg.DebugConfig.Telemetry.MetricsPrefix
+	return px + "_" + name
+}
+
+var forbiddenCharsReplacer = strings.NewReplacer(" ", "_", ".", "_", "=", "_", "-", "_", "/", "_")
+
+// controlled by 'disable_hostname'
+// https://developer.hashicorp.com/consul/docs/agent/config/config-files#telemetry-disable_hostname
+func (c *Consul) promMetricNameWithHostname(name string) string {
+	px := c.cfg.DebugConfig.Telemetry.MetricsPrefix
+	node := forbiddenCharsReplacer.Replace(c.cfg.Config.NodeName)
+
+	return px + "_" + node + "_" + name
+}
+
+func formatFloat(v float64) string {
+	return strconv.FormatFloat(v, 'f', -1, 64)
+}