visionmedia/superagent — pull request #212 by sebastianhoitz (2013-04-25 10:30:24+00:00)
Title: Calculate Content Length of request

I added a method to calculate the content length of a request.

You can use it by calling

```javascript
request.contentLength(function(contentLength) {
request.set("Content-Length", contentLength);
});
```

It automatically considers attachments and field values.
I did not get it to work properly with raw data that was added via send.

See issue #196