adding new content for apimon training

doc/source/internal/apimon_training/epmon_checks.rst

@@ -1,3 +1,5 @@
+.. _EpMon Overview:
+
 ============================
 Endpoint Monitoring overview
 ============================

doc/source/internal/apimon_training/index.rst

@@ -11,6 +11,7 @@ Apimon Training
    test_scenarios
    epmon_checks
    dashboards
+   metrics
    alerts
    notifications
    logs

doc/source/internal/apimon_training/metrics.rst

@@ -0,0 +1,49 @@
+.. _Metrics:
+
+=======
+Metrics
+=======
+
+The ansible playbook scenarios generate metrics in two ways:
+
+-   The Ansible playbook internally invokes method calls to **OpenStack SDK
+    libraries.** They in turn generate metrics about each API call they do. This
+    requires some special configuration in the clouds.yaml file (currently
+    exposing metrics into statsd and InfluxDB is supported). For details refer
+    to the [config
+    documentation](https://docs.openstack.org/openstacksdk/latest/user/guides/stats.html)
+    of the OpenStack SDK. The following metrics are captured:
+    -   response HTTP code
+    -   duration of API call
+    -   name of API call
+    -   method of API call
+    -   service type
+-   Ansible plugins may **expose additional metrics** (i.e. whether the overall
+    scenario succeed or not) with help of [callback
+    plugin](https://github.com/stackmon/apimon/tree/main/apimon/ansible/callback).
+    Since sometimes it is not sufficient to know only the timings of each API
+    call, Ansible callbacks are utilized to report overall execution time and
+    result (whether the scenario succeeded and how long it took). The following
+    metrics are captured:
+    -   test case
+    -   playbook name
+    -   environment
+    -   action name
+    -   result code
+    -   result string
+    -   service type
+    -   state type
+    -   total amount of (failed, passed, ignored, skipped tests)
+
+Custom metrics:
+
+In some situations more complex metric generation is required which consists of
+execution of multiple tasks in scenario. For such cases the tags parameter is
+used. Once the specific tasks in playbook are tagged with some specific metric
+name the metrics are calculated as sum of all executed tasks with respective
+tag. It's useful in cases where measured metric contains multiple steps to
+achieve the desired state of service or service resource. For example boot up of
+virtual machine from deployment until succesfull login via SSH.
+
+	tags: ["metric=delete_server"]
+	tags: ["az={{ availability_zone }}", "service=compute", "metric=create_server{{ metric_suffix }}"]

doc/source/internal/apimon_training/test_scenarios.rst

@@ -1,3 +1,5 @@
+.. _Test Scenarios:
+
 ==============
 Test Scenarios
 ==============