feature/add-profiler (#42)

cmd/root.go

@@ -19,7 +19,9 @@ package cmd
 import (
 	"context"
 	"fmt"
+	golog "log"
 	"os"
+	"runtime/pprof"
 
 	"codeberg.org/scip/esctl/pkg/cfg"
 	"codeberg.org/scip/esctl/pkg/es"
@@ -83,6 +85,12 @@ func Main() int {
 				Usage:       "output mode (tsv, markdown, json, yaml) default: tsv",
 				Destination: &conf.Output,
 			},
+			&cli.StringFlag{
+				Name:        "profile-file",
+				Usage:       "golang profiler output file",
+				Destination: &conf.ProfileFile,
+				Hidden:      true,
+			},
 		},
 
 		Commands: []*cli.Command{
@@ -115,6 +123,26 @@ func Main() int {
 
 			log.Init(conf)
 
+			if conf.ProfileFile != "" {
+				// enable  cpu profiling. Do  NOT use q  to stop the  game but
+				// close the window to get a profile
+				fd, err := os.Create(conf.ProfileFile)
+				if err != nil {
+					return nil, err
+				}
+				defer func() {
+					if err := fd.Close(); err != nil {
+						golog.Fatal(err)
+					}
+				}()
+
+				if err := pprof.StartCPUProfile(fd); err != nil {
+					golog.Fatal(err)
+				}
+
+				defer pprof.StopCPUProfile()
+			}
+
 			return nil, nil
 		},
 	}