在 Windows 服务上通过 WinSCP 下载 SFTP 文件时冻结

Question

我正在尝试构建一个使用 SFTP 下载一些日志文件并将其导入数据库的服务。

因为Delphi没有附带SFTP组件，我创建了一个BAT文件来使用WinSCP下载日志

DownloadLogs.bat:
  WinSCP.com < DownloadLogs.commands

DownloadLogs.commands:
  open sftp://root:password@myserver.com
  option confirm off
  get -delete /var/lib/3cxpbx/Instance1/Data/Logs/CDRLogs files
  exit

这是我的服务：

procedure TsrvCentralita.ServiceExecute(Sender: TService);
const SecondsBetweenExecutions = 10;
var Counter: integer;
    dmLogs: TdmLogs;
begin
  Counter := 0;
  while not Terminated do begin
    Inc(Counter);
    if Counter > SecondsBetweenExecutions then begin
      Counter := 0;
      dmLogs := TdmLogs.Create(Self);
      try
        if dmLogs.DownloadLogs then dmLogs.ImportLogs;
      finally
        dmLogs.Free;
      end;
    end;
    Sleep(1000);
    ServiceThread.ProcessRequests(False);
  end;
end;

这就是我调用 BAT 文件的方式：

function ExecAppWait(AppName: string; Params: string = ''; Directory: string = ''; Hidden: boolean = False): Boolean;
var ShellExInfo: TShellExecuteInfo;
begin
  FillChar(ShellExInfo, SizeOf(ShellExInfo), 0);
  with ShellExInfo do begin
    cbSize := SizeOf(ShellExInfo);
    fMask  := see_Mask_NoCloseProcess;
    Wnd    := Application.Handle;
    lpFile := PChar(AppName);
    lpDirectory  := PChar(Directory);
    lpParameters := PChar(Params);
    if Hidden then nShow := sw_Hide
    else nShow := sw_ShowNormal;
  end;
  Result := ShellExecuteEx(@ShellExInfo);
  if Result then
    while WaitForSingleObject(ShellExInfo.HProcess, 100) = WAIT_TIMEOUT do begin
      Application.ProcessMessages; // give processor time to other tasks
      if Application.Terminated then
        Break;
    end;
end;

function TdmLogs.DownloadLogs(Hidden: boolean = True): boolean;
var Path: string;
begin
  Path := TPath.Combine(TPath.GetDirectoryName(Application.ExeName), 'SFTP');;
  ExecAppWait(TPath.Combine(Path, 'LogsCentralita.bat'), '', Hidden);
  Result := Length(TDirectory.GetFiles(TPath.Combine(Path, 'Files'), '*.log')) > 0
end;

当我在我的应用程序上调试 DownloadLogs 函数时，它工作正常，但是当运行作为服务时它冻结了。你知道哪里出了问题吗？我不能从服务中调用 CMD.exe 吗？

谢谢。

更新

根据 Martin Prikryl 的回答，我现在以这种方式执行 WinSCP：

function TdmCentralita.DownloadLogs(SaveOutput: boolean = False): boolean;
var IniFile: TIniFile;
    Path, Params, User, Password, Server, Hostkey, RemotePath: string;
begin
  IniFile := TIniFile.Create(TPath.ChangeExtension(GetModuleName(HInstance), '.ini'));
  Server := IniFile.ReadString('Centralita', 'Servidor', '');
  Hostkey := IniFile.ReadString('Centralita', 'Hostkey', '');
  User := IniFile.ReadString('Centralita', 'Usuario', 'root');
  Password := DecryptStr(IniFile.ReadString('Centralita', 'Password', ''), 223);
  RemotePath := IniFile.ReadString('Centralita', 'PathRemoto', '');
  IniFile.Free;
  while (RightStr(RemotePath, 1) = '\') or (RightStr(RemotePath, 1) = '/') do RemotePath := Copy(RemotePath, 1, Length(RemotePath) - 1);
  RemotePath := RemotePath + '/*.log';

  Path := TPath.Combine(TPath.GetDirectoryName(GetModuleName(HInstance)), 'SFTP');
  if not TDirectory.Exists(TPath.Combine(Path, 'files')) then TDirectory.CreateDirectory(TPath.Combine(Path, 'files'));
  Params := '/ini=null /command "open sftp://' + User + ':' + Password + '@' + Server + ' -hostkey=""' + Hostkey + '""" "option confirm off" "get -delete ' + RemotePath + ' files\*" "exit"';
  if SaveOutput then Params := Params + ' /log="' + Path + '\Log.txt" /loglevel=0';
  ExecAppWait('WinSCP.com', Params, Path, True);

  Result := Length(TDirectory.GetFiles(TPath.Combine(Path, 'Files'), '*.log')) > 0
end;

Answer 1

您的脚本不包含 SSH 主机密钥。由于您提供命令的方式很奇怪（输入重定向而不是 /script 或 /command 开关），WinSCP 以交互模式启动。所以它提示进行主机密钥验证，然后挂起。

将 -hostkey 开关添加到您的 open 命令。参见：

Verifying the host key in script
My script works fine when executed manually, but fails or hangs when run by Windows Scheduler, SSIS or other automation service. What am I doing wrong?

并使用 /script or /command switches 使 WinSCP 在任何问题上中止，而不是挂起。

您还应该阅读批处理文件输出，以便将来更好地处理错误。

在 Windows 服务上通过 WinSCP 下载 SFTP 文件时冻结

Downloading SFTP files through WinSCP on a Windows Service freezes

windows

delphi

sftp

windows-services

winscp