How to unit test with a file upload in mocha

Question

I have an app built on Express.js and I\'d like to test the file upload functionality. I\'m trying to reproduce the object parsed to req.files (when using express.bodyParser

Answer 1

Changing attach('image') to attach('file') will solve the problem of req.files.file not defined.

var should = require('should'),
    supertest = require('supertest');
var request = supertest('localhost:3000');

describe('upload', function() {
    it('a file', function(done) {
       request.post('/your/endpoint')
              .field({field1: 'xxx', field2: 'yyy'})
              .attach('file', 'path/to/file.jpg')
              .end(function(err, res) {
                  res.should.have.status(200) // 'success' status
                  done()
              });
    });
});

Answer 2

You might try using zombie.js https://github.com/assaf/zombie , it creates a virtual browser for testing with basic functionality. It can attach a file to a specific input field and supports cookies and sessions

related gist : https://gist.github.com/764536

Answer 3

If using request promise you can simply do this, sending formData is built into it:

    var options = {
      method: 'POST',
      uri: base + '/api/image/upload',
      formData: {
        someField: 'someValue',
        anotherField: 'anotherValue',
        file: {
          // path to image
          value: fs.createReadStream('./testImg.png'),
          options: {
            filename: 'testImg.png',
            contentType: 'image/png'
          }
        }
      }
    };
    let resp;
    try {
      resp = await request.post(options);
      body = JSON.parse(resp);
    } catch (e) {
      console.log(e);
      resp = e.response;
      code = resp.statusCode;
      body = JSON.parse(resp.body);
    }
    // access what is returned here, check what needs to be
    assert.equal(code, 200, 'Status: ' + code + ': ' + body.error);
    assert.equal(body.success, true);
    assert.exists(body.image);

Answer 4

Just came across this module by TJ: https://github.com/visionmedia/supertest.

Answer 5

Here is an example of how you would do it with supertest module.

var should = require('should'),
    supertest = require('supertest');
var request = supertest('localhost:3000');

describe('upload', function() {
    it('a file', function(done) {
       request.post('/your/endpoint')
              .field('extra_info', '{"in":"case you want to send json along with your file"}')
              .attach('image', 'path/to/file.jpg')
              .end(function(err, res) {
                  res.should.have.status(200); // 'success' status
                  done();
              });
    });
});

Answer 6

You can do this directly in Mocha but it's a bit tricky. Here's an example posting an image:

var filename = 'x.png'
  , boundary = Math.random()

request(app)
  .post('/g/' + myDraftGallery._id)
  .set('Content-Type', 'multipart/form-data; boundary=' + boundary)
  .write('--' + boundary + '\r\n')
  .write('Content-Disposition: form-data; name="image"; filename="'+filename+'"\r\n')
  .write('Content-Type: image/png\r\n')
  .write('\r\n')
  .write(fs.readFileSync('test/'+filename))
  .write('\r\n--' + boundary + '--')
  .end(function(res){
    res.should.have.status(200)
    done()
  })

The name parameter of Content-Disposition is what your file will be accessible as via req.files (so req.files.image for my example) You can also use an array value like this: name="images[]" and your file(s) will be available via an array, e.g: req.files.images[0]

Also if you're not already using it you should have a look at this (makes mocha/express testing a ~bit~ easier): https://github.com/visionmedia/express/blob/master/test/support/http.js

Edit: Since express 3-beta5, express uses supertest. To look at the old http.js code look here: https://github.com/visionmedia/express/blob/3.0.0beta4/test/support/http.js Or simply move over to supertest..