title: Get Total requests in a period of time
body: <p>I need to show, in Grafana, a panel with the number of requests in the period of time selected in the upper right corner.</p>
  
  <p>For this I need to solve 2 issues here, I will ask the prometheus question here and the Grafana question in another link.</p>
  
  <p>If I have a Counter <code>http_requests_total</code>, How can I build a query to get <strong>an integer</strong> with the total number of requests during a period of time (for example:24hs)?</p>