Add Inner Ring code

pkg/util/profiler/pprof.go

@@ -0,0 +1,44 @@
+package profiler
+
+import (
+	"context"
+	"expvar"
+	"net/http"
+	"net/http/pprof"
+
+	"github.com/spf13/viper"
+	"go.uber.org/zap"
+)
+
+// Profiler is an interface of profiler.
+type Profiler interface {
+	Start(ctx context.Context)
+	Stop()
+}
+
+const profilerKey = "pprof"
+
+// NewProfiler is a profiler's constructor.
+func NewProfiler(l *zap.Logger, v *viper.Viper) Profiler {
+	if !v.GetBool(profilerKey + ".enabled") {
+		l.Debug("pprof server disabled")
+		return nil
+	}
+
+	mux := http.NewServeMux()
+
+	mux.Handle("/debug/vars", expvar.Handler())
+
+	mux.HandleFunc("/debug/pprof/", pprof.Index)
+	mux.HandleFunc("/debug/pprof/cmdline", pprof.Cmdline)
+	mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+	mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	mux.HandleFunc("/debug/pprof/trace", pprof.Trace)
+
+	return newHTTPServer(httpParams{
+		Key:     profilerKey,
+		Viper:   v,
+		Logger:  l,
+		Handler: mux,
+	})
+}