Add missing main API file

internal/metricRouter/metricApi.go

@@ -0,0 +1,232 @@
+package metricRouter
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"sync"
+	"time"
+
+	cclog "github.com/ClusterCockpit/cc-metric-collector/internal/ccLogger"
+	lp "github.com/ClusterCockpit/cc-metric-collector/internal/ccMetric"
+	mct "github.com/ClusterCockpit/cc-metric-collector/internal/multiChanTicker"
+	"github.com/gorilla/mux"
+)
+
+type statsApiConfig struct {
+	PublishCollectorState bool   `json:"publish_collectorstate"`
+	Host                  string `json:"bindhost"`
+	Port                  string `json:"port"`
+}
+
+// Metric cache data structure
+type statsApi struct {
+	name     string
+	input    chan lp.CCMetric
+	indone   chan bool
+	outdone  chan bool
+	config   statsApiConfig
+	wg       *sync.WaitGroup
+	statsWg  sync.WaitGroup
+	ticker   mct.MultiChanTicker
+	tickchan chan time.Time
+	server   *http.Server
+	router   *mux.Router
+	lock     sync.Mutex
+	baseurl  string
+	stats    map[string]map[string]int64
+	outStats map[string]map[string]int64
+}
+
+type StatsApi interface {
+	Start()
+	Close()
+	StatsFunc(w http.ResponseWriter, r *http.Request)
+}
+
+var statsApiServer *statsApi = nil
+
+func (a *statsApi) updateStats(point lp.CCMetric) {
+	switch point.Name() {
+	case "_stats":
+		if name, nok := point.GetMeta("source"); nok {
+			var compStats map[string]int64
+			var ok bool
+
+			if compStats, ok = a.stats[name]; !ok {
+				a.stats[name] = make(map[string]int64)
+				compStats = a.stats[name]
+			}
+			for k, v := range point.Fields() {
+				switch value := v.(type) {
+				case int:
+					compStats[k] = int64(value)
+				case uint:
+					compStats[k] = int64(value)
+				case int32:
+					compStats[k] = int64(value)
+				case uint32:
+					compStats[k] = int64(value)
+				case int64:
+					compStats[k] = int64(value)
+				case uint64:
+					compStats[k] = int64(value)
+				default:
+					cclog.ComponentDebug(a.name, "Unusable stats for", k, ". Values should be int64")
+				}
+			}
+			a.stats[name] = compStats
+		}
+	}
+}
+
+func (a *statsApi) Start() {
+	a.ticker.AddChannel(a.tickchan)
+	a.wg.Add(1)
+	a.statsWg.Add(1)
+	go func() {
+		a.stats = make(map[string]map[string]int64)
+		defer a.statsWg.Done()
+		for {
+			select {
+			case <-a.indone:
+				cclog.ComponentDebug(a.name, "INPUT DONE")
+				close(a.indone)
+				return
+			case p := <-a.input:
+				a.lock.Lock()
+				a.updateStats(p)
+				a.lock.Unlock()
+			}
+		}
+	}()
+	a.statsWg.Add(1)
+	go func() {
+		a.outStats = make(map[string]map[string]int64)
+		defer a.statsWg.Done()
+		a.lock.Lock()
+		for comp, compData := range a.stats {
+			var outData map[string]int64
+			var ok bool
+			if outData, ok = a.outStats[comp]; !ok {
+				outData = make(map[string]int64)
+			}
+			for k, v := range compData {
+				outData[k] = v
+			}
+			a.outStats[comp] = outData
+		}
+		a.lock.Unlock()
+		for {
+			select {
+			case <-a.outdone:
+				cclog.ComponentDebug(a.name, "OUTPUT DONE")
+				close(a.outdone)
+				return
+			case <-a.tickchan:
+				a.lock.Lock()
+				for comp, compData := range a.stats {
+					var outData map[string]int64
+					var ok bool
+					if outData, ok = a.outStats[comp]; !ok {
+						outData = make(map[string]int64)
+					}
+					for k, v := range compData {
+						outData[k] = v
+					}
+					a.outStats[comp] = outData
+				}
+				a.lock.Unlock()
+			}
+		}
+	}()
+	a.statsWg.Add(1)
+	go func() {
+		defer a.statsWg.Done()
+		err := a.server.ListenAndServe()
+		if err != nil && err.Error() != "http: Server closed" {
+			cclog.ComponentError(a.name, err.Error())
+		}
+		cclog.ComponentDebug(a.name, "SERVER DONE")
+	}()
+	cclog.ComponentDebug(a.name, "STARTED")
+}
+
+func (a *statsApi) StatsFunc(w http.ResponseWriter, r *http.Request) {
+	data, err := json.Marshal(a.outStats)
+	if err == nil {
+		w.Header().Set("Content-Type", "application/json")
+		io.WriteString(w, string(data))
+	}
+}
+
+// Close finishes / stops the metric cache
+func (a *statsApi) Close() {
+	cclog.ComponentDebug(a.name, "CLOSE")
+	a.indone <- true
+	a.outdone <- true
+	a.server.Shutdown(context.Background())
+	// wait for close of channel r.done
+	<-a.indone
+	<-a.outdone
+	a.statsWg.Wait()
+	a.wg.Done()
+
+	//a.wg.Wait()
+}
+
+func NewStatsApi(ticker mct.MultiChanTicker, wg *sync.WaitGroup, statsApiConfigfile string) (StatsApi, error) {
+	a := new(statsApi)
+	a.name = "StatsApi"
+	a.config.Host = "localhost"
+	a.config.Port = "8080"
+	configFile, err := os.Open(statsApiConfigfile)
+	if err != nil {
+		cclog.ComponentError(a.name, err.Error())
+		return nil, err
+	}
+	defer configFile.Close()
+	jsonParser := json.NewDecoder(configFile)
+	err = jsonParser.Decode(&a.config)
+	if err != nil {
+		cclog.ComponentError(a.name, err.Error())
+		return nil, err
+	}
+	a.input = make(chan lp.CCMetric)
+	a.ticker = ticker
+	a.tickchan = make(chan time.Time)
+	a.wg = wg
+	a.indone = make(chan bool)
+	a.outdone = make(chan bool)
+	a.router = mux.NewRouter()
+	a.baseurl = fmt.Sprintf("%s:%s", a.config.Host, a.config.Port)
+	a.server = &http.Server{Addr: a.baseurl, Handler: a.router}
+	if a.config.PublishCollectorState {
+		a.router.HandleFunc("/", a.StatsFunc)
+	}
+	statsApiServer = a
+	return a, nil
+}
+
+func ComponentStatInt(component string, key string, value int64) {
+	if statsApiServer == nil {
+		return
+	}
+	y, err := lp.New("_stats", map[string]string{}, map[string]string{"source": component}, map[string]interface{}{key: value}, time.Now())
+	if err == nil {
+		statsApiServer.input <- y
+	}
+}
+
+func ComponentStatString(component string, key string, value int64) {
+	if statsApiServer == nil {
+		return
+	}
+	y, err := lp.New("_stats", map[string]string{}, map[string]string{"source": component}, map[string]interface{}{key: value}, time.Now())
+	if err == nil {
+		statsApiServer.input <- y
+	}
+}