gistfile1.txt

$ curl -v -H "X-Auth-Token: my_token" https://rackspace_api.url/current | python -m json.tool
* Adding handle: conn: 0xe08fb0
* Adding handle: send: 0
* Adding handle: recv: 0
* Curl_addHandleToPipeline: length: 1
* - Conn 0 (0xe08fb0) send_pipe: 1, recv_pipe: 0
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0* About to connect() to rackspace_api.url port 443 (#0)
*   Trying 174.143.139.141...
* Connected to rackspace_api.url (ip) port 443 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
*   CAfile: /etc/pki/tls/certs/ca-bundle.crt
  CApath: none
* SSL connection using SSL_RSA_WITH_RC4_128_SHA
* Server certificate:
*       subject: CN=rackspace_api.url,OU=Domain Validated,OU=Thawte SSL123 certificate,OU=Go to https://www.thawte.com/repository/index.html,O=rackspace_api.url
*       start date: Nov 18 00:00:00 2010 GMT
*       expire date: Nov 17 23:59:59 2015 GMT
*       common name: rackspace_api.url
*       issuer: CN=Thawte DV SSL CA,OU=Domain Validated SSL,O="Thawte, Inc.",C=US
> GET /v1.0/account_id/loadbalancers/lb_id/usage/current HTTP/1.1
> User-Agent: curl/7.33.0
> Host: rackspace_api.url
> Accept: */*
> X-Auth-Token: my_token
>
< HTTP/1.1 200 OK
< Content-Type: application/json
< Via: 1.1 Rackspace Cloud Load Balancer API v1.19.28 (Repose/2.11.0)
< Content-Length: 7265
< Date: Mon, 10 Feb 2014 15:47:28 GMT
* Server Jetty(8.0.y.z-SNAPSHOT) is not blacklisted
< Server: Jetty(8.0.y.z-SNAPSHOT)
<
{ [data not shown]
 53  7265   53  3884    0     0   7158      0  0:00:01 --:--:--  0:00:01  7100  7265  100  7265    0     0  12349      0 --:--:-- --:--:-- --:--:-- 12376
* Connection #0 to host rackspace_api.url left intact
{
    "links": [],
    "loadBalancerUsageRecords": [
        {
            "averageNumConnections": 17.5,
            "averageNumConnectionsSsl": 0.0,
            "endTime": "2014-02-09T17:00:00Z",
            "id": id;
            "incomingTransfer": 3816105,
            "incomingTransferSsl": 0,
            "numPolls": 12,
            "numVips": 1,
            "outgoingTransfer": 529684773,
            "outgoingTransferSsl": 0,
            "sslMode": "OFF",
            "startTime": "2014-02-09T16:00:00Z",
            "vipType": "PUBLIC"
        },
..and so on..

But, I got a doubt in the next item, now I've this set up in collectd.conf

<Plugin curl_json>
  <URL "https://rackspace_api.url/usage/current">
   Instance "Load_Balancer"
    Header "X-Auth-Token: my_token"
   <Key "LoadBalancerUsageRecords/*/averageNumConnections">
     Type "connections"
   </Key>
..