VOL-1868 move simulated onu from voltha-go to voltha-simonu-adapter
Sourced from voltha-go commit 251a11c0ffe60512318a644cd6ce0dc4e12f4018
Change-Id: Iab179bc2f3dd772ed7f488d1c03d1a84ba75e874
diff --git a/vendor/github.com/armon/go-metrics/statsd.go b/vendor/github.com/armon/go-metrics/statsd.go
new file mode 100644
index 0000000..1bfffce
--- /dev/null
+++ b/vendor/github.com/armon/go-metrics/statsd.go
@@ -0,0 +1,184 @@
+package metrics
+
+import (
+ "bytes"
+ "fmt"
+ "log"
+ "net"
+ "net/url"
+ "strings"
+ "time"
+)
+
+const (
+ // statsdMaxLen is the maximum size of a packet
+ // to send to statsd
+ statsdMaxLen = 1400
+)
+
+// StatsdSink provides a MetricSink that can be used
+// with a statsite or statsd metrics server. It uses
+// only UDP packets, while StatsiteSink uses TCP.
+type StatsdSink struct {
+ addr string
+ metricQueue chan string
+}
+
+// NewStatsdSinkFromURL creates an StatsdSink from a URL. It is used
+// (and tested) from NewMetricSinkFromURL.
+func NewStatsdSinkFromURL(u *url.URL) (MetricSink, error) {
+ return NewStatsdSink(u.Host)
+}
+
+// NewStatsdSink is used to create a new StatsdSink
+func NewStatsdSink(addr string) (*StatsdSink, error) {
+ s := &StatsdSink{
+ addr: addr,
+ metricQueue: make(chan string, 4096),
+ }
+ go s.flushMetrics()
+ return s, nil
+}
+
+// Close is used to stop flushing to statsd
+func (s *StatsdSink) Shutdown() {
+ close(s.metricQueue)
+}
+
+func (s *StatsdSink) SetGauge(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
+}
+
+func (s *StatsdSink) SetGaugeWithLabels(key []string, val float32, labels []Label) {
+ flatKey := s.flattenKeyLabels(key, labels)
+ s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
+}
+
+func (s *StatsdSink) EmitKey(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|kv\n", flatKey, val))
+}
+
+func (s *StatsdSink) IncrCounter(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
+}
+
+func (s *StatsdSink) IncrCounterWithLabels(key []string, val float32, labels []Label) {
+ flatKey := s.flattenKeyLabels(key, labels)
+ s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
+}
+
+func (s *StatsdSink) AddSample(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|ms\n", flatKey, val))
+}
+
+func (s *StatsdSink) AddSampleWithLabels(key []string, val float32, labels []Label) {
+ flatKey := s.flattenKeyLabels(key, labels)
+ s.pushMetric(fmt.Sprintf("%s:%f|ms\n", flatKey, val))
+}
+
+// Flattens the key for formatting, removes spaces
+func (s *StatsdSink) flattenKey(parts []string) string {
+ joined := strings.Join(parts, ".")
+ return strings.Map(func(r rune) rune {
+ switch r {
+ case ':':
+ fallthrough
+ case ' ':
+ return '_'
+ default:
+ return r
+ }
+ }, joined)
+}
+
+// Flattens the key along with labels for formatting, removes spaces
+func (s *StatsdSink) flattenKeyLabels(parts []string, labels []Label) string {
+ for _, label := range labels {
+ parts = append(parts, label.Value)
+ }
+ return s.flattenKey(parts)
+}
+
+// Does a non-blocking push to the metrics queue
+func (s *StatsdSink) pushMetric(m string) {
+ select {
+ case s.metricQueue <- m:
+ default:
+ }
+}
+
+// Flushes metrics
+func (s *StatsdSink) flushMetrics() {
+ var sock net.Conn
+ var err error
+ var wait <-chan time.Time
+ ticker := time.NewTicker(flushInterval)
+ defer ticker.Stop()
+
+CONNECT:
+ // Create a buffer
+ buf := bytes.NewBuffer(nil)
+
+ // Attempt to connect
+ sock, err = net.Dial("udp", s.addr)
+ if err != nil {
+ log.Printf("[ERR] Error connecting to statsd! Err: %s", err)
+ goto WAIT
+ }
+
+ for {
+ select {
+ case metric, ok := <-s.metricQueue:
+ // Get a metric from the queue
+ if !ok {
+ goto QUIT
+ }
+
+ // Check if this would overflow the packet size
+ if len(metric)+buf.Len() > statsdMaxLen {
+ _, err := sock.Write(buf.Bytes())
+ buf.Reset()
+ if err != nil {
+ log.Printf("[ERR] Error writing to statsd! Err: %s", err)
+ goto WAIT
+ }
+ }
+
+ // Append to the buffer
+ buf.WriteString(metric)
+
+ case <-ticker.C:
+ if buf.Len() == 0 {
+ continue
+ }
+
+ _, err := sock.Write(buf.Bytes())
+ buf.Reset()
+ if err != nil {
+ log.Printf("[ERR] Error flushing to statsd! Err: %s", err)
+ goto WAIT
+ }
+ }
+ }
+
+WAIT:
+ // Wait for a while
+ wait = time.After(time.Duration(5) * time.Second)
+ for {
+ select {
+ // Dequeue the messages to avoid backlog
+ case _, ok := <-s.metricQueue:
+ if !ok {
+ goto QUIT
+ }
+ case <-wait:
+ goto CONNECT
+ }
+ }
+QUIT:
+ s.metricQueue = nil
+}