golang实现ftp功能简单又实用(示例代码)

FtpServer:
  ListenAddr: ":2121"
  ListenDir: "/data/ftpwww" # ftp目录
  PassivePortRange: # end必须大于start，否则会panic， 非被动模式不用配置
    Start: 3121
    End: 3124
  ListenUsers: # ftp账号
    - Username: ftpadmin
      Password: "123456..."
    - Username: ftpadmin
      Password: "yueduo-654321..."

package config
import (
	"fmt"
	"gopkg.in/yaml.v3"
	"os"
)
var (
	Conf Config
)
type Config struct {
...
	FtpServer  FtpServer  `yaml:"FtpServer"`
...
}
func InitConfigFromYaml(file string) error {
	if file == "" {
		file = "config.yaml"
	}
	f, err := os.Open(file)
	if err != nil {
		return fmt.Errorf("配置文件打开错误.%w", err)
	}
	dec := yaml.NewDecoder(f)
	err = dec.Decode(&Conf)
	if err != nil {
		return err
	}
	return nil
}

//初始化配置文件
	err := config.InitConfigFromYaml(f)
	if err != nil {
		logn.Errorf("配置文件初始化错误,file:%s 错误信息:%v", f, err)
		return
	}
// 加载ftp
	go ftp.FtpDirver()

package ftp
import (
	"fmt"
	"os"
)
// 加载文件权限只读
type ReadOnlyPerm struct{}
func (p *ReadOnlyPerm) GetOwner(path string) (string, error) {
	return "ftp", nil
}
func (p *ReadOnlyPerm) GetGroup(path string) (string, error) {
	return "ftp", nil
}
func (p *ReadOnlyPerm) GetMode(path string) (os.FileMode, error) {
	// 0444: 只读（r--r--r--）
	return 0444, nil
}
func (p *ReadOnlyPerm) ChOwner(path, owner string) error {
	return fmt.Errorf("permission denied")
}
func (p *ReadOnlyPerm) ChGroup(path, group string) error {
	return fmt.Errorf("permission denied")
}
func (p *ReadOnlyPerm) ChMode(path string, mode os.FileMode) error {
	return fmt.Errorf("permission denied")
}

package ftp
import (
	"fmt"
	filedriver "github.com/goftp/file-driver"
	"github.com/goftp/server"
	"io"
	"log"
	"net"
	"os"
	"safe-agent/config"
)
type MultiUserAuth struct {
	users map[string]config.FTPUser
}
type PerUserDriverFactory struct {
	users map[string]config.FTPUser
}
type PerUserFileDriver struct {
	*filedriver.FileDriver
	users map[string]config.FTPUser
}
func (d *PerUserFileDriver) Init(conn *server.Conn) {
	// 🔥 每个用户设置自己的根目录
	d.FileDriver.RootPath = config.Conf.FtpServer.ListenDir
}
func (d *PerUserFileDriver) Delete(path string) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) DeleteFile(path string) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) Rename(from, to string) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) PutFile(destPath string, data io.Reader, appendData bool) (int64, error) {
	return 0, fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) Chmod(path string, mode os.FileMode) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) Remove(path string) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) RemoveDir(path string) error {
	return fmt.Errorf("550 permission denied")
}
func (d *PerUserFileDriver) MakeDir(path string) error {
	return fmt.Errorf("550 permission denied")
}
func (f *PerUserDriverFactory) NewDriver() (server.Driver, error) {
	return &PerUserFileDriver{
		FileDriver: &filedriver.FileDriver{
			Perm: &ReadOnlyPerm{},
		},
		users: f.users,
	}, nil
}
func (a *MultiUserAuth) CheckPasswd(user, pass string) (bool, error) {
	u, ok := a.users[user]
	if !ok {
		return false, nil
	}
	return u.Password == pass, nil
}
func FtpDirver() {
	userMap := make(map[string]config.FTPUser)
	for _, u := range config.Conf.FtpServer.ListenUsers {
		userMap[u.Username] = u
	}
	host, portStr, _ := net.SplitHostPort(config.Conf.FtpServer.ListenAddr)
	port := 0
	if portStr != "" {
		fmt.Sscanf(portStr, "%d", &port)
	}
	passiveRange := config.Conf.FtpServer.PassivePortRange
	passivePorts := fmt.Sprintf("%d-%d", passiveRange.Start, passiveRange.End)
	opts := &server.ServerOpts{
		Factory: &PerUserDriverFactory{
			users: userMap,
		},
		PassivePorts: passivePorts,
		Auth:         &MultiUserAuth{users: userMap},
		Port:         port,
		Hostname:     host,
	}
	//log.Printf("FTP server listening on %s", config.Conf.FtpServer.ListenAddr)
	fmt.Printf(
		"FTP listen=%s passive_ports=%s",
		config.Conf.FtpServer.ListenAddr,
		passivePorts,
	)
	s := server.NewServer(opts)
	log.Fatal(s.ListenAndServe())
}