jetty sessions duration

Author: SylvainJuge

jmx-scraper/src/integrationTest/java/io/opentelemetry/contrib/jmxscraper/target_systems/JettyIntegrationTest.java

@@ -56,6 +56,13 @@ protected void verifyMetrics() {
                 "jetty.session.count",
                 "The number of sessions established in total.",
                 "{sessions}",
+                attrs -> attrs.containsKey("resource")),
+        metric ->
+            assertSumWithAttributes(
+                metric,
+                "jetty.session.time.total",
+                "The total time sessions have been active.",
+                "s",
                 attrs -> attrs.containsKey("resource")));
   }
 }

jmx-scraper/src/main/resources/jetty.yaml

@@ -12,3 +12,8 @@ rules:
         type: counter
         unit: "{sessions}"
         desc: The number of sessions established in total.
+      sessionTimeTotal:
+        metric: time.total
+        type: counter
+        unit: s
+        desc: The total time sessions have been active.