add requests/errors to stats

debug/stats/default.go

@@ -1,18 +1,50 @@
 package stats
 
 import (
+	"runtime"
+	"sync"
+	"time"
+
 	"github.com/micro/go-micro/util/ring"
 )
 
 type stats struct {
+	// used to store past stats
 	buffer *ring.Buffer
+
+	sync.RWMutex
+	started  int64
+	requests uint64
+	errors   uint64
+}
+
+func (s *stats) snapshot() *Stat {
+	s.RLock()
+	defer s.RUnlock()
+
+	var mstat runtime.MemStats
+	runtime.ReadMemStats(&mstat)
+
+	now := time.Now().Unix()
+
+	return &Stat{
+		Timestamp: now,
+		Started:   s.started,
+		Uptime:    now - s.started,
+		Memory:    mstat.Alloc,
+		GC:        mstat.PauseTotalNs,
+		Threads:   uint64(runtime.NumGoroutine()),
+		Requests:  s.requests,
+		Errors:    s.errors,
+	}
 }
 
 func (s *stats) Read() ([]*Stat, error) {
 	// TODO adjustable size and optional read values
-	buf := s.buffer.Get(1)
+	buf := s.buffer.Get(60)
 	var stats []*Stat
 
+	// get a value from the buffer if it exists
 	for _, b := range buf {
 		stat, ok := b.Value.(*Stat)
 		if !ok {
@@ -21,6 +53,9 @@ func (s *stats) Read() ([]*Stat, error) {
 		stats = append(stats, stat)
 	}
 
+	// get a snapshot
+	stats = append(stats, s.snapshot())
+
 	return stats, nil
 }
 
@@ -29,10 +64,26 @@ func (s *stats) Write(stat *Stat) error {
 	return nil
 }
 
+func (s *stats) Record(err error) error {
+	s.Lock()
+	defer s.Unlock()
+
+	// increment the total request count
+	s.requests++
+
+	// increment the error count
+	if err != nil {
+		s.errors++
+	}
+
+	return nil
+}
+
 // NewStats returns a new in memory stats buffer
 // TODO add options
 func NewStats() Stats {
 	return &stats{
-		buffer: ring.New(1024),
+		started: time.Now().Unix(),
+		buffer:  ring.New(60),
 	}
 }

debug/stats/stats.go

@@ -7,6 +7,8 @@ type Stats interface {
 	Read() ([]*Stat, error)
 	// Write a stat snapshot
 	Write(*Stat) error
+	// Record a request
+	Record(error) error
 }
 
 // A runtime stat
@@ -23,4 +25,12 @@ type Stat struct {
 	Threads uint64
 	// Garbage collection in nanoseconds
 	GC uint64
+	// Total requests
+	Requests uint64
+	// Total errors
+	Errors uint64
 }
+
+var (
+	DefaultStats = NewStats()
+)