使用 NodeJs 提供临时文件 [英] Serving Temporary Files with NodeJs

问题描述

我正在构建一个 NodeJs SOAP 客户端.最初，我想象服务器(即节点 SOAP 客户端)将允许通过 REST API 下载文档(REST API 已通过身份验证).在 Google 和 SO 上花了很多时间之后，看起来这是不可能的.

I am building a NodeJs SOAP client. Originally, I imagined the server (ie the node SOAP client) would allow downloading documents through a REST API (the REST API is authenticated). After a good deal of time on Google and SO, looks like that is not possible.

这意味着当请求下载文档时，我必须对文档进行 SOAP 调用，并通过 AJAX 向 REST 客户端返回一个 URL.

That means when a document download is requested, I'll have to make a SOAP call for the document and return a URL to the REST client via AJAX.

为了做到这一点，我需要:

In order to do this I'll need to:

1. 在 Node 中临时创建一个文件
2. 获取其 URL 并返回到 Web 客户端
3. 请求文件并发送响应后，删除文件(出于安全目的)

这是我的问题:

1. 是否已经有一个框架可以做到这一点?临时模块 可能是一种选择，但实际上我想在每次请求后删除，而不是在一段时间后删除.

2. 如果没有，我是否可以仅使用 NodeJs 文件系统来执行此操作，并使用 Express static模块?基本上我们会将静态模块修改为如下所示:

1. Is there already a framework that does this? the temp module might be an option, but really I'd like to delete after every request, not after a time period.

2. If not, can I do this just using the NodeJs File System, and Express static module? Basically we would modify the static module to look like this:

return function static(req, res, next) {
  if ('GET' != req.method && 'HEAD' != req.method) return next();
  var path = parse(req).pathname;
  var pause = utils.pause(req);

/* My Added Code Here */
res.on('end', function(){
    //  delete file based on req URL
})
/* end additions */

function resume() {
  next();
  pause.resume();
}

function directory() {
  if (!redirect) return resume();
  var pathname = url.parse(req.originalUrl).pathname;
  res.statusCode = 301;
  res.setHeader('Location', pathname + '/');
  res.end('Redirecting to ' + utils.escape(pathname) + '/');
}
function error(err) {
   if (404 == err.status) return resume();
  next(err);
}
send(req, path)
  .maxage(options.maxAge || 0)
  .root(root)
  .hidden(options.hidden)
  .on('error', error)
  .on('directory', directory)
  .pipe(res);
};

res.on('end',... 是否有效?或者，我是否应该创建一些中间件来为指向临时文件的 URL 执行此操作?

Is res.on('end',... vaild? Alternatively,should I create some middleware that does this for URLs pointing to the temporary files?

推荐答案

发现两个 SO 问题可以回答我的问题.所以显然我们不需要使用 express.static 中间件.我们只需要文件系统来下载文件:

Found two SO questions that answer my question. So apparently we don't need to use the express.static middleware. We just need the filesystem to download a file:

app.get('/download', function(req, res){
 var file = __dirname + '/upload-folder/dramaticpenguin.MOV';
 res.download(file); // Set disposition and send it.
});

如果我们想流然后删除，请遵循:

app.get('/download', function(req, res){
   var stream = fs.createReadStream('<filepath>/example.pdf', {bufferSize: 64 * 1024})
   stream.pipe(res);

   var had_error = false;
   stream.on('error', function(err){
      had_error = true;
   });
   stream.on('close', function(){
   if (!had_error) fs.unlink('<filepath>/example.pdf');
});

这篇关于使用 NodeJs 提供临时文件的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！