feat(instrumentation): more work

pkg/api/metrics.go

@@ -1,10 +1,12 @@
 package api
 
 import (
-	"github.com/grafana/grafana/pkg/api/dtos"
-	"github.com/grafana/grafana/pkg/middleware"
 	"math/rand"
 	"strconv"
+
+	"github.com/grafana/grafana/pkg/api/dtos"
+	"github.com/grafana/grafana/pkg/metrics"
+	"github.com/grafana/grafana/pkg/middleware"
 )
 
 func GetTestMetrics(c *middleware.Context) {
@@ -34,3 +36,35 @@ func GetTestMetrics(c *middleware.Context) {
 
 	c.JSON(200, &result)
 }
+
+func GetInternalMetrics(c middleware.Context) Response {
+	snapshots := metrics.MetricStats.GetSnapshots()
+
+	resp := make(map[string]interface{})
+
+	for _, m := range snapshots {
+		metricName := m.Name() + m.StringifyTags()
+
+		switch metric := m.(type) {
+		case metrics.Counter:
+			resp[metricName] = map[string]interface{}{
+				"count": metric.Count(),
+			}
+		case metrics.Timer:
+			percentiles := metric.Percentiles([]float64{0.25, 0.75, 0.90, 0.99})
+			resp[metricName] = map[string]interface{}{
+				"count": metric.Count(),
+				"min":   metric.Min(),
+				"max":   metric.Max(),
+				"mean":  metric.Mean(),
+				"std":   metric.StdDev(),
+				"p25":   percentiles[0],
+				"p75":   percentiles[1],
+				"p90":   percentiles[2],
+				"p99":   percentiles[3],
+			}
+		}
+	}
+
+	return Json(200, resp)
+}