Uploading images using Node.js, Express, and Mongoose

I'll answer my own question for the first time. I found an example straight from the source. Please forgive the poor indentation. I wasn't sure how to indent properly when copying and pasting. The code comes straight from Express multipart/form-data example on GitHub.

// Expose modules in ./support for demo purposes
require.paths.unshift(__dirname + '/../../support');

/**
 * Module dependencies.
 */

var express = require('../../lib/express')
  , form = require('connect-form');

var app = express.createServer(
  // connect-form (http://github.com/visionmedia/connect-form)
  // middleware uses the formidable middleware to parse urlencoded
  // and multipart form data
  form({ keepExtensions: true })
);

app.get('/', function(req, res){
  res.send('<form method="post" enctype="multipart/form-data">'
    + '<p>Image: <input type="file" name="image" /></p>'
    + '<p><input type="submit" value="Upload" /></p>'
    + '</form>');
});

app.post('/', function(req, res, next){

  // connect-form adds the req.form object
  // we can (optionally) define onComplete, passing
  // the exception (if any) fields parsed, and files parsed
  req.form.complete(function(err, fields, files){
    if (err) {
      next(err);
    } else {
      console.log('\nuploaded %s to %s'
        ,  files.image.filename
        , files.image.path);
      res.redirect('back');
    }
  });

  // We can add listeners for several form
  // events such as "progress"
  req.form.on('progress', function(bytesReceived, bytesExpected){
    var percent = (bytesReceived / bytesExpected * 100) | 0;
    process.stdout.write('Uploading: %' + percent + '\r');
  });
});

app.listen(3000);
console.log('Express app started on port 3000');

Since you're using express, just add bodyParser:

app.use(express.bodyParser());

then your route automatically has access to the uploaded file(s) in req.files:

app.post('/todo/create', function (req, res) {
    // TODO: move and rename the file using req.files.path & .name)
    res.send(console.dir(req.files));  // DEBUG: display available fields
});

If you name the input control "todo" like this (in Jade):

form(action="/todo/create", method="POST", enctype="multipart/form-data")
    input(type='file', name='todo')
    button(type='submit') New

Then the uploaded file is ready by the time you get the path and original filename in 'files.todo':

  • req.files.todo.path, and
  • req.files.todo.name

other useful req.files properties:

  • size (in bytes)
  • type (e.g., 'image/png')
  • lastModifiedate
  • _writeStream.encoding (e.g, 'binary')