xmlhttprequest does not support binary data response in node

[stevedw]

When using engine.io-client in node application/octet responses are ignored by the client as xmlhttprequest does not support the response field.

e.g
// line 465 on xmlhttprequest

 response.on('data', function(chunk) {
          // Make sure there's some data
          if (chunk) {
            self.responseText += chunk;
          }
          // Don't emit state changes if the connection has been aborted.
          if (sendFlag) {
            setState(self.LOADING);
          }
        });

the polling xhr transport is only looking for xhr.response which is never set:
//polling-xhr.js

Request.prototype.onLoad = function(){
  var data;
  try {
    var contentType;
    try {
      contentType = this.xhr.getResponseHeader('Content-Type').split(';')[0];
    } catch (e) {}
   if (contentType === 'application/octet-stream') {
      data = this.xhr.response;
    } else {
      if (!this.supportsBinary) {
        data = this.xhr.responseText;
      } else {
        data = 'ok';
      }
    }
  } catch (e) {
    this.onError(e);
  }
  if (null != data) {
    this.onData(data);
  }
};

The data object is there always null on the response.
Would you consider moving to something like xhr2 instead as this does support binary payloads?

[darrachequesne]

Closed by #483, thanks for the report.