first commit

api.go

@@ -0,0 +1,161 @@
+package metric
+
+import (
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/facebookgo/stats"
+)
+
+var (
+	// pkgClis stores pkgClients
+	pkgClis = map[string]*pkgClient{}
+	// pkgClis protects pkgClis
+	pkgClisLock = sync.RWMutex{}
+	// default counter paramters
+	counterParams = struct {
+		window, bucket time.Duration
+	}{window: 15 * time.Minute, bucket: time.Minute}
+	// default histogram parameters
+	histogramParams = struct {
+		window, bucket time.Duration
+	}{window: 5 * time.Minute, bucket: time.Minute}
+)
+
+// Counter defines interface for counter
+type Counter interface {
+	// Incr increments value to the counter
+	Incr(value float64)
+	// Snapshot return the snapshot of the counter
+	Snapshot() CounterSnapshot
+}
+
+// Histogram defines interface for counter
+type Histogram interface {
+	// Update add value to the histogram
+	Update(value float64)
+	// Snapshot returns the snapshot of the histogrom
+	Snapshot() HistSnapshot
+}
+
+// Snapshot includes CounterSnapshot, HistogramSnapshot and name
+type Snapshot interface {
+	CounterSnapshot
+	HistSnapshot
+	// HasHistogram returns whether this snapshot contains histogram
+	HasHistogram() bool
+	// Pkg returns the package of Histogram
+	Pkg() string
+	// Name returns the package of Histogram Name
+	Name() string
+}
+
+// CounterSnapshot defines interface for accessing counter with following methods
+type CounterSnapshot interface {
+	// SliceIn returns statistics of each bucket in the given duration
+	SliceIn(dur time.Duration) []Bucket
+	// AggrIn returns aggregration statistics in the given duration
+	AggrIn(dur time.Duration) Bucket
+}
+
+// HistSnapshot represents a snapshot of a histogram
+type HistSnapshot interface {
+	// List histogram bins
+	Bins() []Bin
+	// Return export percentail values of the histogram
+	Percentiles([]float64) ([]float64, int64)
+}
+
+// Bucket represents the snapshot of a counter bucket, including
+// statistics values like count, sum, average, min, max and bucket start/end
+// time.
+type Bucket struct {
+	Count float64
+	Sum   float64
+	Min   float64
+	Max   float64
+	Avg   float64
+	Start time.Time
+	End   time.Time
+}
+
+// Bin represents the snapshot of a histogram bin, including bin couner and
+// its lower and upper bound
+type Bin struct {
+	Count int64
+	Lower float64
+	Upper float64
+}
+
+// NewClient creates an instance of facebookgo/stats implementation with
+// the given pkg name and preifx.
+func NewClient(pkg, prefix string) stats.Client {
+	pkgClisLock.Lock()
+	defer pkgClisLock.Unlock()
+
+	pc, ok := pkgClis[pkg]
+	if !ok {
+		pc = newClient(pkg)
+		pkgClis[pkg] = pc
+	}
+	if prefix == "" {
+		return pc
+	}
+	if !strings.HasSuffix(prefix, ".") {
+		prefix += "."
+	}
+	return stats.PrefixClient([]string{prefix}, pc)
+}
+
+// GetSnapshot returns shapshot of counters and histograms matched the
+// given pkg and name
+func GetSnapshot(qpkg string, qname string) []Snapshot {
+	pkgClisLock.RLock()
+	defer pkgClisLock.RUnlock()
+
+	snapshots := []Snapshot{}
+	for _, pc := range pkgClis {
+		if qpkg != "*" && !strings.Contains(pc.pkg, qpkg) {
+			continue
+		}
+		snapshots = append(snapshots, pc.get(qname)...)
+	}
+	return snapshots
+}
+
+// GetPkgs lista all package names
+func GetPkgs(showEmpty bool) []string {
+	pkgClisLock.RLock()
+	result := make([]string, 0, len(pkgClis))
+	for pkg, cli := range pkgClis {
+		if showEmpty || cli.size() > 0 {
+			result = append(result, pkg)
+		}
+	}
+	pkgClisLock.RUnlock()
+
+	sort.Strings(result)
+	return result
+}
+
+// SetCounterParam sets the parameters of counter and histogram
+func SetCounterParam(window, bucket time.Duration) error {
+	if err := check(window, bucket); err != nil {
+		return err
+	}
+	counterParams.window = window
+	counterParams.bucket = bucket
+	return nil
+}
+
+// SetHistogramParam sets the parameters of counter and histogram
+func SetHistogramParam(window, bucket time.Duration) error {
+	if err := check(window, bucket); err != nil {
+		return err
+	}
+	histogramParams.window = window
+	histogramParams.bucket = bucket
+	return nil
+}

api_test.go

@@ -0,0 +1,92 @@
+package metric
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/suite"
+)
+
+// TestCase counter
+type SuiteAPI struct {
+	suite.Suite
+	factory *mockFactory
+}
+
+func (s *SuiteAPI) SetupTest() {
+	pkgClis = map[string]*pkgClient{}
+	s.factory = &mockFactory{}
+
+	newCounter = s.factory.NewCounter
+	newHistogram = s.factory.NewHist
+}
+
+func (s *SuiteAPI) TestNewClient() {
+	defer s.add("aaa", "ccc.ddd", 10, 2, 1)()
+
+	c := NewClient("aaa", "")
+	c.BumpAvg("ccc.ddd", 10)
+	c.BumpHistogram("ccc.ddd", 10)
+
+	ss := GetSnapshot("aaa", "ccc.ddd")
+	s.Equal(len(ss), 1)
+	s.Equal(ss[0].Pkg(), "aaa")
+	s.Equal(ss[0].Name(), "ccc.ddd")
+	s.True(ss[0].HasHistogram())
+
+	ss = GetSnapshot("*", "*")
+	s.Equal(len(ss), 1)
+	s.True(ss[0].HasHistogram())
+}
+
+func (s *SuiteAPI) TestNewClientWithPrefix() {
+	defer s.add("aaa", "ccc.ddd", 10, 6, 0)()
+
+	c1 := NewClient("aaa", "ccc")
+	c1.BumpAvg("ddd", 10)
+	c1.BumpSum("ddd", 10)
+
+	c2 := NewClient("aaa", "ccc.")
+	c2.BumpAvg("ddd", 10)
+	c2.BumpSum("ddd", 10)
+
+	c3 := NewClient("aaa", "")
+	c3.BumpAvg("ccc.ddd", 10)
+	c3.BumpSum("ccc.ddd", 10)
+
+	ss := GetSnapshot("aaa", "ccc.ddd")
+	s.Equal(len(ss), 1)
+	s.Equal(ss[0].Pkg(), "aaa")
+	s.Equal(ss[0].Name(), "ccc.ddd")
+	s.False(ss[0].HasHistogram())
+}
+
+func (s *SuiteAPI) TestGetPkgs() {
+	s.add("aaa", "aaa.bbb", 10, 1, 0)
+	s.add("bbb", "ccc.ddd", 20, 1, 0)
+
+	c1 := NewClient("aaa", "")
+	c2 := NewClient("bbb", "")
+	_ = NewClient("ccc", "")
+
+	c1.BumpSum("aaa.bbb", 10)
+	c2.BumpSum("ccc.ddd", 20)
+
+	s.Equal(GetPkgs(false), []string{
+		"aaa",
+		"bbb",
+	})
+
+	s.Equal(GetPkgs(true), []string{
+		"aaa",
+		"bbb",
+		"ccc",
+	})
+}
+
+func (s *SuiteAPI) add(pkg, name string, v float64, ct, ht int) func() {
+	return addTestData(s.T(), s.factory, pkg, name, v, ct, ht)
+}
+
+func TestRunSuiteAPI(t *testing.T) {
+	suite.Run(t, new(SuiteAPI))
+}