dmctl: fix dmctl command to improve its usability (#1750)

cmd/dm-ctl/main.go

@@ -14,72 +14,18 @@
 package main
 
 import (
-	"context"
-	"flag"
 	"fmt"
-	"io"
 	"os"
 	"os/signal"
-	"strings"
 	"syscall"
 
-	"github.com/chzyer/readline"
-	"github.com/pingcap/errors"
-
 	"github.com/pingcap/dm/dm/ctl"
 	"github.com/pingcap/dm/dm/ctl/common"
 	"github.com/pingcap/dm/pkg/log"
 	"github.com/pingcap/dm/pkg/terror"
-	"github.com/pingcap/dm/pkg/utils"
 )
 
-// output:
-// Usage: dmctl [global options] command [command options] [arguments...]
-//
-// Available Commands:
-//  ...
-//  query-status          query-status [-s source ...] [task-name]
-//  ...
-//
-// Special Commands:
-//  --encrypt encrypt plaintext to ciphertext
-//  ...
-//
-// Global Options:
-//  --V prints version and exit
-//  ...
-func helpUsage(cfg *common.Config) {
-	fmt.Println("Usage: dmctl [global options] command [command options] [arguments...]")
-	fmt.Println()
-	ctl.PrintUsage()
-	fmt.Println()
-	fmt.Println("Special Commands:")
-	f := cfg.FlagSet.Lookup(common.EncryptCmdName)
-	fmt.Printf("  --%s %s\n", f.Name, f.Usage)
-	f = cfg.FlagSet.Lookup(common.DecryptCmdName)
-	fmt.Printf("  --%s %s\n", f.Name, f.Usage)
-	fmt.Println()
-	fmt.Println("Global Options:")
-	cfg.FlagSet.VisitAll(func(flag2 *flag.Flag) {
-		if flag2.Name == common.EncryptCmdName || flag2.Name == common.DecryptCmdName {
-			return
-		}
-		fmt.Printf("  --%s %s\n", flag2.Name, flag2.Usage)
-	})
-}
-
 func main() {
-	cfg := common.NewConfig()
-	args := os.Args[1:]
-
-	// no arguments: print help message about dmctl
-	if len(args) == 0 {
-		helpUsage(cfg)
-		os.Exit(0)
-	}
-
-	args = aliasArgs(args)
-
 	// now, we use checker in dmctl while it using some pkg which log some thing when running
 	// to make dmctl output more clear, simply redirect log to file rather output to stdout
 	err := log.InitLogger(&log.Config{
@@ -91,100 +37,6 @@ func main() {
 		os.Exit(2)
 	}
 
-	// try to split one task operation from dmctl command
-	// because we allow user put task operation at last with two restrictions
-	// 1. one command one task operation
-	// 2. put task operation at last
-	cmdArgs := extractSubCommand(args)
-	lenArgs := len(args)
-	lenCmdArgs := len(cmdArgs)
-	if lenCmdArgs > 0 {
-		lenArgs -= lenCmdArgs
-	}
-
-	finished, err := cfg.Parse(args[:lenArgs])
-	if finished {
-		os.Exit(0)
-	}
-
-	switch errors.Cause(err) {
-	case nil:
-	case flag.ErrHelp:
-		if lenCmdArgs > 0 {
-			// print help message about special subCommand
-			ctl.PrintHelp(cmdArgs)
-		} else {
-			// print help message about dmctl
-			helpUsage(cfg)
-		}
-		os.Exit(0)
-	default:
-		// NOTE: when `--help` in cmdArgs we need to print out the help msg.
-		for _, cmd := range cmdArgs {
-			if cmd == "--help" {
-				ctl.PrintHelp(cmdArgs)
-				os.Exit(0)
-			}
-		}
-		common.PrintLinesf("parse cmd flags err: %s", terror.Message(err))
-		os.Exit(2)
-	}
-
-	err = cfg.Validate()
-	if err != nil {
-		common.PrintLinesf("flags are not validate: %s", terror.Message(err))
-		os.Exit(2)
-	}
-
-	err = ctl.Init(cfg)
-	if err != nil {
-		common.PrintLinesf("%v", terror.Message(err))
-		os.Exit(2)
-	}
-	if lenCmdArgs > 0 {
-		if err = commandMode(cmdArgs); err != nil {
-			os.Exit(2)
-		}
-	} else {
-		interactionMode()
-	}
-}
-
-func extractSubCommand(args []string) []string {
-	collectedArgs := make([]string, 0, len(args))
-	subCommand := make([]string, 0, len(args))
-	for i := 0; i < len(args); i++ {
-		// check whether has multiple commands
-		if ctl.HasCommand(strings.ToLower(args[i])) {
-			subCommand = append(subCommand, args[i])
-		}
-	}
-	if len(subCommand) == 0 {
-		return collectedArgs
-	}
-	if len(subCommand) > 1 {
-		fmt.Printf("command mode only support one command at a time, find %d:", len(subCommand))
-		fmt.Println(subCommand)
-		os.Exit(1)
-	}
-
-	for i := 0; i < len(args); i++ {
-		if ctl.HasCommand(strings.ToLower(args[i])) {
-			collectedArgs = append(collectedArgs, args[i:]...)
-			break
-		}
-	}
-	return collectedArgs
-}
-
-func commandMode(args []string) error {
-	return ctl.Start(args)
-}
-
-func interactionMode() {
-	utils.PrintInfo2("dmctl")
-	fmt.Println() // print a separater
-
 	sc := make(chan os.Signal, 1)
 	signal.Notify(sc,
 		syscall.SIGHUP,
@@ -194,7 +46,7 @@ func interactionMode() {
 
 	go func() {
 		sig := <-sc
-		fmt.Printf("got signal [%v] to exit", sig)
+		fmt.Printf("\nGot signal [%v] to exit.\n", sig)
 		switch sig {
 		case syscall.SIGTERM:
 			os.Exit(0)
@@ -203,73 +55,5 @@ func interactionMode() {
 		}
 	}()
 
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-	go common.SyncMasterEndpoints(ctx)
-
-	loop()
-
-	fmt.Println("dmctl exit")
-}
-
-func loop() {
-	l, err := readline.NewEx(&readline.Config{
-		Prompt:          "\033[31m»\033[0m ",
-		HistoryFile:     "/tmp/dmctlreadline.tmp",
-		InterruptPrompt: "^C",
-		EOFPrompt:       "^D",
-	})
-	if err != nil {
-		panic(err)
-	}
-
-	for {
-		line, err := l.Readline()
-		if err != nil {
-			if err == readline.ErrInterrupt {
-				break
-			} else if err == io.EOF {
-				break
-			}
-			continue
-		}
-
-		line = strings.TrimSpace(line)
-		if line == "exit" {
-			l.Close()
-			os.Exit(0)
-		} else if line == "" {
-			continue
-		}
-
-		args := strings.Fields(line)
-		args = aliasArgs(args)
-		err = ctl.Start(args)
-		if err != nil {
-			fmt.Println("fail to run:", args)
-		}
-
-		syncErr := log.L().Sync()
-		if syncErr != nil {
-			fmt.Fprintln(os.Stderr, "sync log failed", syncErr)
-		}
-	}
-	l.Close()
-}
-
-func aliasArgs(args []string) []string {
-	args = aliasGetTaskCfgCmd(args)
-	return args
-}
-
-func aliasGetTaskCfgCmd(args []string) []string {
-	for i, arg := range args {
-		if arg == "get-task-config" {
-			args = append(args[:i+1], args[i:]...)
-			args[i] = "get-config"
-			args[i+1] = "task"
-			return args
-		}
-	}
-	return args
+	ctl.MainStart(common.AdjustArgumentsForPflags(os.Args[1:]))
 }