VOL-1867 move simulated olt from voltha-go to voltha-simolt-adapter
Sourced from voltha-go commit 251a11c0ffe60512318a644cd6ce0dc4e12f4018
Change-Id: I8e7ee4da1fed739b3c461917301d2729a79307f5
diff --git a/vendor/github.com/armon/go-metrics/statsite.go b/vendor/github.com/armon/go-metrics/statsite.go
new file mode 100644
index 0000000..6c0d284
--- /dev/null
+++ b/vendor/github.com/armon/go-metrics/statsite.go
@@ -0,0 +1,172 @@
+package metrics
+
+import (
+ "bufio"
+ "fmt"
+ "log"
+ "net"
+ "net/url"
+ "strings"
+ "time"
+)
+
+const (
+ // We force flush the statsite metrics after this period of
+ // inactivity. Prevents stats from getting stuck in a buffer
+ // forever.
+ flushInterval = 100 * time.Millisecond
+)
+
+// NewStatsiteSinkFromURL creates an StatsiteSink from a URL. It is used
+// (and tested) from NewMetricSinkFromURL.
+func NewStatsiteSinkFromURL(u *url.URL) (MetricSink, error) {
+ return NewStatsiteSink(u.Host)
+}
+
+// StatsiteSink provides a MetricSink that can be used with a
+// statsite metrics server
+type StatsiteSink struct {
+ addr string
+ metricQueue chan string
+}
+
+// NewStatsiteSink is used to create a new StatsiteSink
+func NewStatsiteSink(addr string) (*StatsiteSink, error) {
+ s := &StatsiteSink{
+ addr: addr,
+ metricQueue: make(chan string, 4096),
+ }
+ go s.flushMetrics()
+ return s, nil
+}
+
+// Close is used to stop flushing to statsite
+func (s *StatsiteSink) Shutdown() {
+ close(s.metricQueue)
+}
+
+func (s *StatsiteSink) SetGauge(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
+}
+
+func (s *StatsiteSink) SetGaugeWithLabels(key []string, val float32, labels []Label) {
+ flatKey := s.flattenKeyLabels(key, labels)
+ s.pushMetric(fmt.Sprintf("%s:%f|g\n", flatKey, val))
+}
+
+func (s *StatsiteSink) EmitKey(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|kv\n", flatKey, val))
+}
+
+func (s *StatsiteSink) IncrCounter(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
+}
+
+func (s *StatsiteSink) IncrCounterWithLabels(key []string, val float32, labels []Label) {
+ flatKey := s.flattenKeyLabels(key, labels)
+ s.pushMetric(fmt.Sprintf("%s:%f|c\n", flatKey, val))
+}
+
+func (s *StatsiteSink) AddSample(key []string, val float32) {
+ flatKey := s.flattenKey(key)
+ s.pushMetric(fmt.Sprintf("%s:%f|ms\n", flatKey, val))
+}
+
+func (s *StatsiteSink) 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 *StatsiteSink) 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 *StatsiteSink) 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 *StatsiteSink) pushMetric(m string) {
+ select {
+ case s.metricQueue <- m:
+ default:
+ }
+}
+
+// Flushes metrics
+func (s *StatsiteSink) flushMetrics() {
+ var sock net.Conn
+ var err error
+ var wait <-chan time.Time
+ var buffered *bufio.Writer
+ ticker := time.NewTicker(flushInterval)
+ defer ticker.Stop()
+
+CONNECT:
+ // Attempt to connect
+ sock, err = net.Dial("tcp", s.addr)
+ if err != nil {
+ log.Printf("[ERR] Error connecting to statsite! Err: %s", err)
+ goto WAIT
+ }
+
+ // Create a buffered writer
+ buffered = bufio.NewWriter(sock)
+
+ for {
+ select {
+ case metric, ok := <-s.metricQueue:
+ // Get a metric from the queue
+ if !ok {
+ goto QUIT
+ }
+
+ // Try to send to statsite
+ _, err := buffered.Write([]byte(metric))
+ if err != nil {
+ log.Printf("[ERR] Error writing to statsite! Err: %s", err)
+ goto WAIT
+ }
+ case <-ticker.C:
+ if err := buffered.Flush(); err != nil {
+ log.Printf("[ERR] Error flushing to statsite! 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
+}