simple http example that increments a metric on request

examples/http_counter/server.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+
+	"github.com/performancecopilot/speed"
+)
+
+var metric *speed.PCPSingletonMetric
+
+func main() {
+
+	var err error
+	metric, err = speed.NewPCPSingletonMetric(
+		0,
+		"http.requests",
+		speed.Int32Type,
+		speed.CounterSemantics,
+		speed.OneUnit,
+		"Number of Requests",
+		"Counter that increments every request",
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	writer, err := speed.NewPCPWriter("example", speed.ProcessFlag)
+	if err != nil {
+		panic(err)
+	}
+
+	err = writer.Register(metric)
+	if err != nil {
+		panic(err)
+	}
+
+	err = writer.Start()
+	if err != nil {
+		panic(err)
+	}
+	defer writer.Stop()
+
+	http.HandleFunc("/increment", handleIncrement)
+	go http.ListenAndServe(":8080", nil)
+
+	fmt.Println("To stop the server press enter")
+	os.Stdin.Read(make([]byte, 1))
+	os.Exit(0)
+}
+
+func handleIncrement(w http.ResponseWriter, r *http.Request) {
+	v := metric.Val().(int32)
+	v++
+	metric.Set(v)
+	fmt.Fprintf(w, "incremented\n")
+}