新增：SFTP直连+连接池+autoConnect+文件服务器端口自动回退

- SFTP模块：连接/断开/文件CRUD/系统信息采集/base64二进制写入 - 连接池：多服务器同时在线，瞬间切换profile - autoConnect：启动时自动连接所有非本地服务器 - 端口自动回退：listenWithFallback消除TOCTOU，解决端口冲突崩溃 - 文件服务器URL集中管理：file-server.ts消除8+处硬编码端口 - Sidebar设置面板：添加服务器/自动连接/自动刷新开关 - 修复：validateFilePath越界panic、正则预编译 - 修复：注释准确性（RemoveAll/端口8073/动态端口文档）
2026-05-04 15:33:19 +08:00
parent 6eaaa56eb6
commit 6bee55b96f
41 changed files with 2620 additions and 458 deletions
--- a/internal/sftp/client.go
+++ b/internal/sftp/client.go
@@ -0,0 +1,260 @@
+package sftp
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/pkg/sftp"
+	"golang.org/x/crypto/ssh"
+)
+
+// Client SFTP 客户端封装（单连接）
+type Client struct {
+	config    *Config
+	client    *sftp.Client
+	sshClient *ssh.Client
+	mu        sync.Mutex
+}
+
+// Manager 全局 SFTP 连接管理器（以 host:port 为 key 的连接池）
+type Manager struct {
+	clients sync.Map // map[string]*Client
+}
+
+var globalManager = &Manager{}
+
+// GetManager 获取全局连接管理器
+func GetManager() *Manager {
+	return globalManager
+}
+
+// Connect 创建或复用 SFTP 连接
+func (m *Manager) Connect(config *Config) (*Client, error) {
+	key := fmt.Sprintf("%s:%d", config.Host, config.Port)
+
+	if existing, ok := m.clients.Load(key); ok {
+		c := existing.(*Client)
+		if c.IsHealthy() {
+			return c, nil
+		}
+		c.Close()
+		m.clients.Delete(key)
+	}
+
+	c, err := newClient(config)
+	if err != nil {
+		return nil, err
+	}
+
+	m.clients.Store(key, c)
+	return c, nil
+}
+
+// GetClient 获取已有连接（不复用也不新建）
+func (m *Manager) GetClient(connID string) *Client {
+	if val, ok := m.clients.Load(connID); ok {
+		return val.(*Client)
+	}
+	return nil
+}
+
+// Disconnect 关闭并移除指定连接
+func (m *Manager) Disconnect(host string, port int) {
+	key := fmt.Sprintf("%s:%d", host, port)
+	if val, ok := m.clients.LoadAndDelete(key); ok {
+		val.(*Client).Close()
+	}
+}
+
+// Shutdown 关闭所有连接
+func (m *Manager) Shutdown() {
+	m.clients.Range(func(key, value any) bool {
+		value.(*Client).Close()
+		m.clients.Delete(key)
+		return true
+	})
+}
+
+// --- 内部 ---
+
+func newClient(config *Config) (*Client, error) {
+	sshConfig := &ssh.ClientConfig{
+		Config: ssh.Config{
+			KeyExchanges: []string{
+				"curve25519-sha256", "curve25519-sha256@libssh.org",
+				"ecdh-sha2-nistp256", "ecdh-sha2-nistp384",
+				"diffie-hellman-group14-sha256", "diffie-hellman-group14-sha1",
+			},
+		},
+		User:            config.Username,
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+		Timeout:         config.Timeout,
+	}
+
+	// 认证方式选择
+	if config.KeyPath != "" {
+		key, err := os.ReadFile(config.KeyPath)
+		if err != nil {
+			return nil, &ConnectionError{Op: "auth", Err: fmt.Errorf("读取密钥文件失败: %w", err)}
+		}
+		var signer ssh.Signer
+		if config.KeyPassphrase != "" {
+			signer, err = ssh.ParsePrivateKeyWithPassphrase(key, []byte(config.KeyPassphrase))
+		} else {
+			signer, err = ssh.ParsePrivateKey(key)
+		}
+		if err != nil {
+			return nil, &ConnectionError{Op: "auth", Err: fmt.Errorf("解析密钥失败: %w", err)}
+		}
+		sshConfig.Auth = []ssh.AuthMethod{ssh.PublicKeys(signer)}
+	} else if config.Password != "" {
+			pw := config.Password
+			sshConfig.Auth = []ssh.AuthMethod{
+			ssh.Password(pw),
+			ssh.KeyboardInteractive(func(user, instruction string, questions []string, echos []bool) ([]string, error) {
+				answers := make([]string, len(questions))
+				for i := range questions {
+					answers[i] = pw
+				}
+				return answers, nil
+			}),
+		}
+	} else {
+		return nil, &ConnectionError{Op: "auth", Err: fmt.Errorf("必须提供密码或密钥文件")}
+	}
+
+	addr := fmt.Sprintf("%s:%d", config.Host, config.Port)
+	sshConn, err := net.DialTimeout("tcp", addr, config.Timeout)
+	if err != nil {
+		return nil, &ConnectionError{Op: "dial", Err: err}
+	}
+
+	sshConnConn, chans, reqs, err := ssh.NewClientConn(sshConn, addr, sshConfig)
+	if err != nil {
+		sshConn.Close()
+		return nil, &ConnectionError{Op: "handshake", Err: err}
+	}
+
+	sshClient := ssh.NewClient(sshConnConn, chans, reqs)
+	sftpClient, err := sftp.NewClient(sshClient)
+	if err != nil {
+		sshClient.Close()
+		return nil, &ConnectionError{Op: "sftp_init", Err: err}
+	}
+
+	return &Client{
+		config:    config,
+		client:    sftpClient,
+		sshClient: sshClient,
+	}, nil
+}
+
+// IsHealthy 检查连接是否健康（先取引用再解锁，避免持锁做 I/O）
+func (c *Client) IsHealthy() bool {
+	c.mu.Lock()
+	client := c.client
+	c.mu.Unlock()
+	if client == nil {
+		return false
+	}
+	_, err := client.Stat("/")
+	return err == nil
+}
+
+// WithRetry 带重试的操作执行（自动处理断线重连）
+func (c *Client) WithRetry(fn func(*sftp.Client) error) error {
+	const maxRetries = 3
+	var lastErr error
+
+	for attempt := 0; attempt < maxRetries; attempt++ {
+		if attempt > 0 {
+			time.Sleep(time.Duration((attempt+1)*2) * time.Second)
+			if reconnectErr := c.reconnect(); reconnectErr != nil {
+				lastErr = reconnectErr
+				continue
+			}
+		}
+
+		c.mu.Lock()
+		client := c.client
+		c.mu.Unlock()
+
+		if client == nil {
+			lastErr = fmt.Errorf("SFTP 客户端未初始化")
+			continue
+		}
+
+		if err := fn(client); err != nil {
+			if isNetworkError(err) {
+				lastErr = err
+				continue
+			}
+			return err
+		}
+		return nil
+	}
+	return fmt.Errorf("操作失败（已重试 %d 次）: %w", maxRetries, lastErr)
+}
+
+func (c *Client) reconnect() error {
+	nc, err := newClient(c.config)
+	if err != nil {
+		return err
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.closeLocked()
+	c.client = nc.client
+	c.sshClient = nc.sshClient
+	return nil
+}
+
+func (c *Client) Close() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.closeLocked()
+}
+
+func (c *Client) closeLocked() {
+	if c.client != nil {
+		c.client.Close()
+		c.client = nil
+	}
+	if c.sshClient != nil {
+		c.sshClient.Close()
+		c.sshClient = nil
+	}
+}
+
+// RunCommand 通过 SSH Session 执行远程命令，返回 stdout
+func (c *Client) RunCommand(cmd string) (string, error) {
+	c.mu.Lock()
+	sshClient := c.sshClient
+	c.mu.Unlock()
+
+	if sshClient == nil {
+		return "", fmt.Errorf("SSH 客户端未初始化")
+	}
+
+	session, err := sshClient.NewSession()
+	if err != nil {
+		return "", fmt.Errorf("创建 SSH 会话失败: %w", err)
+	}
+	defer session.Close()
+
+	out, err := session.CombinedOutput(cmd)
+	if err != nil {
+		return "", fmt.Errorf("执行命令失败 [%s]: %w", cmd, err)
+	}
+	return string(out), nil
+}
+
+// RawClient 获取底层 sftp.Client（高级用法）
+func (c *Client) RawClient() *sftp.Client {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.client
+}