refactor: optimize error messages caused by improper use

internal/cmd/command.go

@@ -90,6 +90,8 @@ Execute commands on target hosts.`,
 		task.SetCommand(shellCommand)
 
 		task.Start()
+
+		util.CobraCheckErrWithHelp(cmd, task.CheckErr())
 	},
 }
 

internal/cmd/fetch.go

@@ -79,6 +79,8 @@ Copy files/dirs from target hosts to local.`,
 		task.SetFetchOptions(localDstDir, tmpDir)
 
 		task.Start()
+
+		util.CobraCheckErrWithHelp(cmd, task.CheckErr())
 	},
 }
 

internal/cmd/push.go

@@ -115,6 +115,8 @@ Copy local files/dirs to target hosts.`,
 		task.SetPushOptions(fileDstPath, allowOverwrite)
 
 		task.Start()
+
+		util.CobraCheckErrWithHelp(cmd, task.CheckErr())
 	},
 }
 
@@ -134,4 +136,15 @@ func init() {
 		false,
 		"allow overwrite files/dirs if they already exist on target hosts",
 	)
+
+	pushCmd.SetHelpFunc(func(command *cobra.Command, strings []string) {
+		util.CobraMarkHiddenGlobalFlags(
+			command,
+			"run.sudo",
+			"run.as-user",
+			"run.lang",
+		)
+
+		command.Parent().HelpFunc()(command, strings)
+	})
 }

internal/cmd/script.go

@@ -85,6 +85,8 @@ Execute a local shell script on target hosts.`,
 		task.SetScriptOptions(destPath, remove, force)
 
 		task.Start()
+
+		util.CobraCheckErrWithHelp(cmd, task.CheckErr())
 	},
 }
 

internal/cmd/vault/decrypt.go

@@ -45,11 +45,11 @@ Decrypt content encrypted by vault.`,
     $ gossh vault decrypt GOSSH-AES256:a5c1b3c0cdad4669f84 -V /path/vault-password-file`,
 	Args: func(cmd *cobra.Command, args []string) error {
 		if len(args) < 1 {
-			util.CheckErr("requires one arg to represent the vault encrypted content")
+			util.CobraCheckErrWithHelp(cmd, "requires one arg to represent the vault encrypted content")
 		}
 
 		if len(args) > 1 {
-			util.CheckErr("to many args, only need one")
+			util.CobraCheckErrWithHelp(cmd, "to many args, only need one")
 		}
 
 		if !aes.IsAES256CipherText(args[0]) {
@@ -66,6 +66,6 @@ Decrypt content encrypted by vault.`,
 		}
 		util.CheckErr(err)
 
-		fmt.Println(plainText)
+		fmt.Printf("\n%s\n", plainText)
 	},
 }

internal/cmd/vault/encrypt.go

@@ -45,23 +45,24 @@ Encrypt sensitive content.`,
     $ gossh vault encrypt your-sensitive-content -V /path/vault-password-file`,
 	Args: func(cmd *cobra.Command, args []string) error {
 		if len(args) < 1 {
-			util.CheckErr("requires one arg to represent the plaintxt to be encrypted")
+			util.CobraCheckErrWithHelp(cmd, "requires one arg to represent the plaintxt to be encrypted")
 		}
 
 		if len(args) > 1 {
-			util.CheckErr("to many args, only need one")
+			util.CobraCheckErrWithHelp(cmd, "to many args, only need one")
 		}
 
 		return nil
 	},
 	Run: func(cmd *cobra.Command, args []string) {
 		vaultPass := getVaultConfirmPassword()
+
 		encryptContent, err := aes.AES256Encode(args[0], vaultPass)
 		if err != nil {
 			err = fmt.Errorf("encrypt failed: %w", err)
 		}
 		util.CheckErr(err)
 
-		fmt.Println(encryptContent)
+		fmt.Printf("\n%s\n", encryptContent)
 	},
 }

internal/pkg/sshtask/sshtask.go

@@ -111,6 +111,8 @@ type Task struct {
 
 	taskOutput   chan taskResult
 	detailOutput chan detailResult
+
+	err error
 }
 
 // NewTask ...
@@ -227,7 +229,8 @@ func (t *Task) BatchRun() {
 
 	allHosts, err := t.getAllHosts()
 	if err != nil {
-		util.CheckErr(err)
+		t.err = err
+		return
 	}
 
 	log.Debugf("got target hosts, count: %d", len(allHosts))
@@ -251,29 +254,31 @@ func (t *Task) BatchRun() {
 	switch t.taskType {
 	case CommandTask:
 		if t.command == "" {
-			util.CheckErr(errors.New("need flag '-e/--execute' or '-L/--hosts.list'"))
+			t.err = errors.New("need flag '-e/--execute' or '-L/--hosts.list'")
 		}
 	case ScriptTask:
 		if t.scriptFile == "" {
-			util.CheckErr(errors.New("need flag '-e/--execute' or '-L/--hosts.list'"))
+			t.err = errors.New("need flag '-e/--execute' or '-L/--hosts.list'")
 		}
 	case PushTask:
 		if t.pushFiles == nil || len(t.pushFiles.files) == 0 {
-			util.CheckErr(errors.New("need flag '-f/--files' or '-L/--hosts.list'"))
+			t.err = errors.New("need flag '-f/--files' or '-L/--hosts.list'")
 		}
 	case FetchTask:
 		if len(t.fetchFiles) == 0 {
-			util.CheckErr(errors.New("need flag '-f/--files' or '-L/--hosts.list'"))
-		}
-
-		if len(t.dstDir) == 0 {
-			util.CheckErr(errors.New("need flag '-d/--dest-path' or '-L/--hosts.list'"))
+			t.err = errors.New("need flag '-f/--files' or '-L/--hosts.list'")
+		} else if len(t.dstDir) == 0 {
+			t.err = errors.New("need flag '-d/--dest-path' or '-L/--hosts.list'")
+		} else {
+			if !util.DirExists(t.dstDir) {
+				err := os.MkdirAll(t.dstDir, os.ModePerm)
+				util.CheckErr(err)
+			}
 		}
+	}
 
-		if !util.DirExists(t.dstDir) {
-			err := os.MkdirAll(t.dstDir, os.ModePerm)
-			util.CheckErr(err)
-		}
+	if t.err != nil {
+		return
 	}
 
 	t.buildSSHClient()
@@ -348,6 +353,11 @@ func (t *Task) HandleOutput() {
 	}
 }
 
+// CheckErr ...
+func (t *Task) CheckErr() error {
+	return t.err
+}
+
 func (t *Task) getAllHosts() ([]string, error) {
 	var hosts []string
 
@@ -392,17 +402,15 @@ func (t *Task) getAllHosts() ([]string, error) {
 	}
 
 	if len(hosts) == 0 {
-		return nil, fmt.Errorf("no target hosts provided")
+		return nil, fmt.Errorf("need target hosts, you can specify hosts file by flag '-H' or " +
+			"provide host/pattern as positional arguments")
 	}
 
 	return util.RemoveDuplStr(hosts), nil
 }
 
 func (t *Task) buildSSHClient() {
-	var (
-		sshClient *batchssh.Client
-		err       error
-	)
+	var sshClient *batchssh.Client
 
 	password, err := t.getPassword()
 	if err != nil {
@@ -414,7 +422,7 @@ func (t *Task) buildSSHClient() {
 	if t.configFlags.Proxy.Server != "" {
 		proxyAuths := t.getProxySSHAuthMethods(&password)
 
-		sshClient, err = batchssh.NewClient(
+		sshClient = batchssh.NewClient(
 			t.configFlags.Auth.User,
 			password,
 			auths,
@@ -430,7 +438,7 @@ func (t *Task) buildSSHClient() {
 			),
 		)
 	} else {
-		sshClient, err = batchssh.NewClient(
+		sshClient = batchssh.NewClient(
 			t.configFlags.Auth.User,
 			password,
 			auths,
@@ -441,10 +449,6 @@ func (t *Task) buildSSHClient() {
 		)
 	}
 
-	if err != nil {
-		util.CheckErr(err)
-	}
-
 	t.sshClient = sshClient
 }
 

pkg/batchssh/batchssh.go

@@ -83,11 +83,7 @@ type Proxy struct {
 }
 
 // NewClient session.
-func NewClient(
-	user, password string,
-	auths []ssh.AuthMethod,
-	options ...func(*Client),
-) (*Client, error) {
+func NewClient(user, password string, auths []ssh.AuthMethod, options ...func(*Client)) *Client {
 	client := Client{
 		User:           user,
 		Password:       password,
@@ -103,7 +99,7 @@ func NewClient(
 		option(&client)
 	}
 
-	return &client, nil
+	return &client
 }
 
 // BatchRun command on remote servers.

pkg/util/cobra.go

@@ -7,6 +7,19 @@ import (
 	"github.com/spf13/pflag"
 )
 
+// CobraCheckErrWithHelp instead of cobra default behavior.
+func CobraCheckErrWithHelp(cmd *cobra.Command, errMsg interface{}) {
+	if errMsg != nil {
+		PrintErr(errMsg)
+
+		_ = cmd.Help()
+
+		fmt.Println()
+
+		CheckErr(errMsg)
+	}
+}
+
 // CobraMarkHiddenGlobalFlags that from params.
 func CobraMarkHiddenGlobalFlags(command *cobra.Command, flags ...string) {
 	for _, v := range flags {

pkg/util/error.go

@@ -36,3 +36,10 @@ func CheckErr(msg interface{}) {
 		os.Exit(1)
 	}
 }
+
+// PrintErr with red color if err not nil.
+func PrintErr(msg interface{}) {
+	if msg != nil {
+		fmt.Fprintln(os.Stderr, color.RedString("Error:"), msg)
+	}
+}