[NOD-853] Add profiler server to kaspaminer (#664)

cmd/kaspaminer/config.go

@@ -2,11 +2,13 @@ package main
 
 import (
 	"fmt"
-	"github.com/kaspanet/kaspad/config"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
+	"github.com/kaspanet/kaspad/config"
+
 	"github.com/kaspanet/kaspad/util"
 	"github.com/pkg/errors"
 
@@ -37,6 +39,7 @@ type configFlags struct {
 	Verbose        bool   `long:"verbose" short:"v" description:"Enable logging of RPC requests"`
 	NumberOfBlocks uint64 `short:"n" long:"numblocks" description:"Number of blocks to mine. If omitted, will mine until the process is interrupted."`
 	BlockDelay     uint64 `long:"block-delay" description:"Delay for block submission (in milliseconds). This is used only for testing purposes."`
+	Profile        string `long:"profile" description:"Enable HTTP profiling on given port -- NOTE port must be between 1024 and 65536"`
 	config.NetworkFlags
 }
 
@@ -78,6 +81,13 @@ func parseConfig() (*configFlags, error) {
 		return nil, errors.New("--rpccert should be omitted if --notls is used")
 	}
 
+	if cfg.Profile != "" {
+		profilePort, err := strconv.Atoi(cfg.Profile)
+		if err != nil || profilePort < 1024 || profilePort > 65535 {
+			return nil, errors.New("The profile port must be between 1024 and 65535")
+		}
+	}
+
 	initLog(defaultLogFile, defaultErrLogFile)
 
 	return cfg, nil

cmd/kaspaminer/main.go

@@ -2,11 +2,16 @@ package main
 
 import (
 	"fmt"
-	"github.com/kaspanet/kaspad/version"
+	"net"
+	"net/http"
 	"os"
 
+	"github.com/kaspanet/kaspad/version"
+
 	"github.com/pkg/errors"
 
+	_ "net/http/pprof"
+
 	"github.com/kaspanet/kaspad/signal"
 	"github.com/kaspanet/kaspad/util/panics"
 )
@@ -28,6 +33,17 @@ func main() {
 		enableRPCLogging()
 	}
 
+	// Enable http profiling server if requested.
+	if cfg.Profile != "" {
+		spawn(func() {
+			listenAddr := net.JoinHostPort("", cfg.Profile)
+			log.Infof("Profile server listening on %s", listenAddr)
+			profileRedirect := http.RedirectHandler("/debug/pprof", http.StatusSeeOther)
+			http.Handle("/", profileRedirect)
+			log.Errorf("%s", http.ListenAndServe(listenAddr, nil))
+		})
+	}
+
 	client, err := connectToServer(cfg)
 	if err != nil {
 		panic(errors.Wrap(err, "Error connecting to the RPC server"))