I'm using SFDC's REST API to access org data. According to the docs (https://www.salesforce.com/us/developer/docs/api_rest/Content/headers_api_usage.htm), each request to the REST API should return a Sforce-Limit-Info header stating the the amount of API requests used, and the amount of remaining requests (on the 24 hours period).
I used curl to perform a test request to the "versions" REST resource, something like this
curl https://naxx.salesforce.com/services/data/ -H 'Authorization: Bearer accesstoken'
The first request returned the Sforce-Limit-Info header
HTTP/1.1 200 OK Date: Mon, 20 Oct 2014 15:02:23 GMT Set-Cookie: BrowserId=xxx;Path=/;Domain=.salesforce.com;Expires=Fri, 19-Dec-2014 15:02:23 GMT Expires: Thu, 01 Jan 1970 00:00:00 GMT Sforce-Limit-Info: api-usage=2/15000 Content-Type: application/json;charset=UTF-8 Transfer-Encoding: chunked
Then I performed the same exact request again, but this one didn't return the header.
HTTP/1.1 200 OK Date: Mon, 20 Oct 2014 15:39:14 GMT Set-Cookie: BrowserId=xxx;Path=/;Domain=.salesforce.com;Expires=Fri, 19-Dec-2014 15:39:14 GMT Expires: Thu, 01 Jan 1970 00:00:00 GMT Content-Type: application/json;charset=UTF-8 Transfer-Encoding: chunked
Subsequent requests do not return the header either.
According to the docs the header should be returned on ALL requests, but this isn't the case. Anyone has experienced this issue? Is there anything I should do to ensure the header is included in the HTTP response? If this is a bug, do you know of any workaround?