Add collector for monitoring the execution of cc-metric-collector itself (#81)

* Add collector to monitor execution of cc-metric-collector itself

* Register SelfCollector

* Fix import paths for moved packages

collectors/selfMetric.go

@@ -0,0 +1,144 @@
+package collectors
+
+import (
+	"encoding/json"
+	"runtime"
+	"syscall"
+	"time"
+
+	cclog "github.com/ClusterCockpit/cc-metric-collector/pkg/ccLogger"
+	lp "github.com/ClusterCockpit/cc-metric-collector/pkg/ccMetric"
+)
+
+type SelfCollectorConfig struct {
+	MemStats   bool `json:"read_mem_stats"`
+	GoRoutines bool `json:"read_goroutines"`
+	CgoCalls   bool `json:"read_cgo_calls"`
+	Rusage     bool `json:"read_rusage"`
+}
+
+type SelfCollector struct {
+	metricCollector
+	config SelfCollectorConfig // the configuration structure
+	meta   map[string]string   // default meta information
+	tags   map[string]string   // default tags
+}
+
+func (m *SelfCollector) Init(config json.RawMessage) error {
+	var err error = nil
+	m.name = "SelfCollector"
+	m.setup()
+	m.parallel = true
+	m.meta = map[string]string{"source": m.name, "group": "Self"}
+	m.tags = map[string]string{"type": "node"}
+	if len(config) > 0 {
+		err = json.Unmarshal(config, &m.config)
+		if err != nil {
+			cclog.ComponentError(m.name, "Error reading config:", err.Error())
+			return err
+		}
+	}
+	m.init = true
+	return err
+}
+
+func (m *SelfCollector) Read(interval time.Duration, output chan lp.CCMetric) {
+	timestamp := time.Now()
+
+	if m.config.MemStats {
+		var memstats runtime.MemStats
+		runtime.ReadMemStats(&memstats)
+
+		y, err := lp.New("total_alloc", m.tags, m.meta, map[string]interface{}{"value": memstats.TotalAlloc}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_alloc", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapAlloc}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_sys", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapSys}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_idle", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapIdle}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_inuse", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapInuse}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_released", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapReleased}, timestamp)
+		if err == nil {
+			y.AddMeta("unit", "Bytes")
+			output <- y
+		}
+		y, err = lp.New("heap_objects", m.tags, m.meta, map[string]interface{}{"value": memstats.HeapObjects}, timestamp)
+		if err == nil {
+			output <- y
+		}
+	}
+	if m.config.GoRoutines {
+		y, err := lp.New("num_goroutines", m.tags, m.meta, map[string]interface{}{"value": runtime.NumGoroutine()}, timestamp)
+		if err == nil {
+			output <- y
+		}
+	}
+	if m.config.CgoCalls {
+		y, err := lp.New("num_cgo_calls", m.tags, m.meta, map[string]interface{}{"value": runtime.NumCgoCall()}, timestamp)
+		if err == nil {
+			output <- y
+		}
+	}
+	if m.config.Rusage {
+		var rusage syscall.Rusage
+		err := syscall.Getrusage(syscall.RUSAGE_SELF, &rusage)
+		if err == nil {
+			sec, nsec := rusage.Utime.Unix()
+			t := float64(sec) + (float64(nsec) * 1e-9)
+			y, err := lp.New("rusage_user_time", m.tags, m.meta, map[string]interface{}{"value": t}, timestamp)
+			if err == nil {
+				y.AddMeta("unit", "seconds")
+				output <- y
+			}
+			sec, nsec = rusage.Stime.Unix()
+			t = float64(sec) + (float64(nsec) * 1e-9)
+			y, err = lp.New("rusage_system_time", m.tags, m.meta, map[string]interface{}{"value": t}, timestamp)
+			if err == nil {
+				y.AddMeta("unit", "seconds")
+				output <- y
+			}
+			y, err = lp.New("rusage_vol_ctx_switch", m.tags, m.meta, map[string]interface{}{"value": rusage.Nvcsw}, timestamp)
+			if err == nil {
+				output <- y
+			}
+			y, err = lp.New("rusage_invol_ctx_switch", m.tags, m.meta, map[string]interface{}{"value": rusage.Nivcsw}, timestamp)
+			if err == nil {
+				output <- y
+			}
+			y, err = lp.New("rusage_signals", m.tags, m.meta, map[string]interface{}{"value": rusage.Nsignals}, timestamp)
+			if err == nil {
+				output <- y
+			}
+			y, err = lp.New("rusage_major_pgfaults", m.tags, m.meta, map[string]interface{}{"value": rusage.Majflt}, timestamp)
+			if err == nil {
+				output <- y
+			}
+			y, err = lp.New("rusage_minor_pgfaults", m.tags, m.meta, map[string]interface{}{"value": rusage.Minflt}, timestamp)
+			if err == nil {
+				output <- y
+			}
+		}
+
+	}
+}
+
+func (m *SelfCollector) Close() {
+	m.init = false
+}