What Headers are Required When Integrating with Force.com?

If you are integrating vWork with force.com, you will need to include the following headers with your request:

HttpRequest req = new HttpRequest();

req.setHeader('Accept-Encoding','gzip');

req.setheader('Content-type', 'text/xml');

req.setMethod('POST');

req.setBody(xmlString);

req.setTimeout(120000);