add observer

internal/util/stats/stats.go

@@ -0,0 +1,62 @@
+package stats
+
+import (
+	"sync"
+
+	"github.com/go-gost/core/observer"
+	"github.com/go-gost/x/stats"
+)
+
+type HandlerStats struct {
+	service string
+	stats   map[string]*stats.Stats
+	mu      sync.RWMutex
+}
+
+func NewHandlerStats(service string) *HandlerStats {
+	return &HandlerStats{
+		service: service,
+		stats:   make(map[string]*stats.Stats),
+	}
+}
+
+func (p *HandlerStats) Stats(client string) *stats.Stats {
+	p.mu.RLock()
+	pstats := p.stats[client]
+	p.mu.RUnlock()
+	if pstats != nil {
+		return pstats
+	}
+
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	pstats = p.stats[client]
+	if pstats == nil {
+		pstats = &stats.Stats{}
+	}
+	p.stats[client] = pstats
+
+	return pstats
+}
+
+func (p *HandlerStats) Events() (events []observer.Event) {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+
+	for k, v := range p.stats {
+		if !v.IsUpdated() {
+			continue
+		}
+		events = append(events, stats.StatsEvent{
+			Kind:         "handler",
+			Service:      p.service,
+			Client:       k,
+			TotalConns:   v.Get(stats.KindTotalConns),
+			CurrentConns: v.Get(stats.KindCurrentConns),
+			InputBytes:   v.Get(stats.KindInputBytes),
+			OutputBytes:  v.Get(stats.KindOutputBytes),
+			TotalErrs:    v.Get(stats.KindTotalErrs),
+		})
+	}
+	return
+}