cli: refactor to allow definition of subcommands next to their implementation

client/pprof.go

@@ -1,17 +1,48 @@
 package client
 
 import (
+	"errors"
+	"github.com/zrepl/zrepl/cli"
 	"github.com/zrepl/zrepl/config"
 	"github.com/zrepl/zrepl/daemon"
 	"log"
 	"os"
 )
 
-type PProfArgs struct {
+var pprofArgs struct {
 	daemon.PprofServerControlMsg
 }
 
-func RunPProf(conf *config.Config, args PProfArgs) {
+var PprofCmd = &cli.Subcommand{
+	Use:   "pprof off | [on TCP_LISTEN_ADDRESS]",
+	Short: "start a http server exposing go-tool-compatible profiling endpoints at TCP_LISTEN_ADDRESS",
+	Run: func(subcommand *cli.Subcommand, args []string) error {
+		if len(args) < 1 {
+			goto enargs
+		}
+		switch args[0] {
+		case "on":
+			pprofArgs.Run = true
+			if len(args) != 2 {
+				return errors.New("must specify TCP_LISTEN_ADDRESS as second positional argument")
+			}
+			pprofArgs.HttpListenAddress = args[1]
+		case "off":
+			if len(args) != 1 {
+				goto enargs
+			}
+			pprofArgs.Run = false
+		}
+
+		RunPProf(subcommand.Config())
+		return nil
+	enargs:
+		return errors.New("invalid number of positional arguments")
+
+	},
+}
+
+func RunPProf(conf *config.Config) {
 	log := log.New(os.Stderr, "", 0)
 
 	die := func() {
@@ -26,7 +57,7 @@ func RunPProf(conf *config.Config, args PProfArgs) {
 		log.Printf("error creating http client: %s", err)
 		die()
 	}
-	err = jsonRequestResponse(httpc, daemon.ControlJobEndpointPProf, args.PprofServerControlMsg, struct{}{})
+	err = jsonRequestResponse(httpc, daemon.ControlJobEndpointPProf, pprofArgs.PprofServerControlMsg, struct{}{})
 	if err != nil {
 		log.Printf("error sending control message: %s", err)
 		die()