How to upload a file and then display its contents in Node.Js Express app?

Question

I'm trying to find an answer to this question for a long time: I need to upload a text/html file through my Node.Js express app and to save its contents into a variable for further treatment.

I can make the multipart form, of course, and post the content, but what I can access so far is only req.files which contains information about the file, but not the actual contents.

How do I get the actual text/html contents from the file?

I don't want to save it to my server, just pass on the content to my app and get rid of the file, so I don't want to use a module like formidable .

Can anyone help please?

Thank you!

Answer 1

Use multer https://github.com/expressjs/multer with the option inMemory: true .

As a crude example you'll want to do something like this.

app.post('test', function(req, res, next) {
  var result = ''; 
  multer({
    inMemory: true,
    onFileUploadData: function(file, data) {
      result += data;
    },  
    onFileUploadComplete: function(file) {
      console.log(result); // This is what you want
    }   
  })(req, res, next);
});

Answer 2

The file is saved by default in a temporary folder (likely /tmp). You need to open the file, read its contents, and then delete it.

You'll want to use this API: http://nodejs.org/api/fs.html

And you could do this:

fs = require('fs');

fs.readFile(req.files.path, function (err, data) {
  if (err) throw err;
  // data will contain your file contents
  console.log(data)

  // delete file
  fs.unlink(req.files.path, function (err) {
    if (err) throw err;
    console.log('successfully deleted ' + req.files.path);
  });      
});