sftp_util

README

sftp_util

Example Go-lang command-line utility for SFTP

• Uses the "github.com/pkg/sftp" and "golang.org/x/crypto/ssh" packages
• Implements GET, PUT, RM and LS
• Preserves the unix file permissions (FileInfo.Mode)

How to use the package

Confugre the settings for your file transfer, as well as server and credentials, in the SftpUtil struct. The following comments explain the fields to configure:

type SftpUtil struct {
	Rdir      string // Remote directory
	Ldir      string // Local directory
	Filename  string // File to transfer
	Type      string // GET or PUT
	User      string // Username
	Pass      string // Password
	Host      string // Hostname or IP Address
	Port      string // TCP port
	Client    *sftp.Client
}

The routine GetCmdLine() reads comand-line flags to specify the file details and type of transfer. These parameters set the first four fields in the above struct.

Sample Code

A sample main() routine for making a stand-alone sftp utilty is provided in sftp-cmd/sftp-cmd.go

package main

import (
	"fmt"
	"github.com/DavidSantia/sftp_util"
)

func main() {
	sftp := &sftp_util.SftpSettings{}
	err := sftp.GetCmdLine()
	if err != nil {
		fmt.Printf("Command-line error: %v\n", err)
		return
	}
	sftp.User = "USER"
	sftp.Pass = "PASSWORD"
	sftp.Host = "HOST"
	sftp.Port = "22"

	// Open SSH session
	err = sftp.Connect()
	if err != nil {
		fmt.Printf("Connect error: %v\n", err)
		return
	}
	defer sftp.Client.Close()

	if sftp.Type == "GET" {
		err = sftp.GetFile()
		if err != nil {
			fmt.Printf("GET error: %v\n", err)
			return
		}
	} else if sftp.Type == "PUT" {
		err = sftp.PutFile()
		if err != nil {
			fmt.Printf("PUT error: %v\n", err)
			return
		}
	} else if sftp.Type == "RM" {
		err = sftp.RmFile()
		if err != nil {
			fmt.Printf("RM error: %v\n", err)
			return
		}
	} else {
		err = sftp.LsDir()
		if err != nil {
			fmt.Printf("LS error: %v\n", err)
			return
		}
	}
}

Building the project

You can buid directly:

$ cd sftp-cmd
$ go build

Alternatively, a build script is provided that builds for linux using a Docker container:

$ ./build.sh

Running the utility

The utility takes the following flags:

Usage of ./sftp-cmd:
  -file string
    	File to transfer
  -ldir string
    	Local directory (default ".")
  -nochmod
    	Don't attempt to set remote file permissions
  -rdir string
    	Remote directory (default ".")
  -type string
    	GET, PUT, RM or LS (required)

Documentation

Index

• Constants
• func DoNothing(hostname string, remote net.Addr, key ssh.PublicKey) (err error)
• type SftpSettings
  • func (sftpSettings *SftpSettings) Connect() (err error)
  • func (util *SftpSettings) GetCmdLine() (err error)
  • func (sftpSettings *SftpSettings) GetFile() (err error)
  • func (sftpSettings *SftpSettings) LsDir() (err error)
  • func (sftpSettings *SftpSettings) PutFile() (err error)
  • func (sftpSettings *SftpSettings) RmFile() (err error)

Constants

const SFTP_BUFSIZE = 131072

Byte buffer for file I/O (128K)

Functions

func DoNothing

func DoNothing(hostname string, remote net.Addr, key ssh.PublicKey) (err error)

Types

type SftpSettings

type SftpSettings struct {
	NoChmod   bool
	Rdir      string // Remote directory
	Ldir      string // Local directory
	Filename  string // File to transfer
	Type      string // GET or PUT
	User      string // Username
	Pass      string // Password
	KeyFile   string // RSA Key file
	Host      string // Hostname or IP Address
	Port      string // TCP port
	Client    *sftp.Client
	SshClient *ssh.Client
}

func (*SftpSettings) Connect

func (sftpSettings *SftpSettings) Connect() (err error)

func (*SftpSettings) GetCmdLine

func (util *SftpSettings) GetCmdLine() (err error)

func (*SftpSettings) GetFile

func (sftpSettings *SftpSettings) GetFile() (err error)

func (*SftpSettings) LsDir

func (sftpSettings *SftpSettings) LsDir() (err error)

func (*SftpSettings) PutFile

func (sftpSettings *SftpSettings) PutFile() (err error)

func (*SftpSettings) RmFile

func (sftpSettings *SftpSettings) RmFile() (err error)