Add Query Apdex Prometheus metric to usage ping

- Update lib/gitlab/usage_data/topology.rb to
  add the query_apdex_weekly_average metric by using
  the new topology_query_apdex_weekly_average method
  to calculate the rolling 7 day average over the
  gitlab_usage_ping:sql_duration_apdex:ratio_rate5m
  prometheus metric
- Add query_apdex_weekly_average to the topology_spec
- Add query_apdex_weekly_average to the usage_ping doc

changelogs/unreleased/227305-add-query-apdex-prometheus-metric-to-usage-ping.yml

+---
+title: Add the Query Apdex Prometheus metric to usage ping
+merge_request: 39256
+author:
+type: other

doc/development/telemetry/usage_ping.md

@@ -747,6 +747,7 @@ The following is example content of the Usage Ping payload.
   "topology": {
     "duration_s": 0.013836685999194742,
     "application_requests_per_hour": 4224,
+    "query_apdex_weekly_average": 0.996,
     "failures": [],
     "nodes": [
       {

lib/gitlab/usage_data/topology.rb

@@ -43,6 +43,7 @@ module Gitlab
         with_prometheus_client(fallback: {}) do |client|
           {
             application_requests_per_hour: topology_app_requests_per_hour(client),
+            query_apdex_weekly_average: topology_query_apdex_weekly_average(client),
             nodes: topology_node_data(client)
           }.compact
         end
@@ -63,6 +64,16 @@ module Gitlab
         (result['value'].last.to_f * 1.hour).to_i
       end
 
+      def topology_query_apdex_weekly_average(client)
+        result = query_safely('gitlab_usage_ping:sql_duration_apdex:ratio_rate5m', 'query_apdex', fallback: nil) do |query|
+          client.query(aggregate_one_week(query)).first
+        end
+
+        return unless result
+
+        result['value'].last.to_f
+      end
+
       def topology_node_data(client)
         # node-level data
         by_instance_mem = topology_node_memory(client)

spec/lib/gitlab/usage_data/topology_spec.rb

@@ -23,6 +23,7 @@ RSpec.describe Gitlab::UsageData::Topology do
         it 'contains node level metrics for each instance' do
           expect_prometheus_api_to(
             receive_app_request_volume_query,
+            receive_query_apdex_ratio_query,
             receive_node_memory_query,
             receive_node_memory_utilization_query,
             receive_node_cpu_count_query,
@@ -38,6 +39,7 @@ RSpec.describe Gitlab::UsageData::Topology do
           expect(subject[:topology]).to eq({
             duration_s: 0,
             application_requests_per_hour: 36,
+            query_apdex_weekly_average: 0.996,
             failures: [],
             nodes: [
               {
@@ -107,6 +109,7 @@ RSpec.describe Gitlab::UsageData::Topology do
         it 'removes the respective entries and includes the failures' do
           expect_prometheus_api_to(
             receive_app_request_volume_query(result: []),
+            receive_query_apdex_ratio_query(result: []),
             receive_node_memory_query(result: []),
             receive_node_memory_utilization_query(result: []),
             receive_node_cpu_count_query,
@@ -123,6 +126,7 @@ RSpec.describe Gitlab::UsageData::Topology do
             duration_s: 0,
             failures: [
               { 'app_requests' => 'empty_result' },
+              { 'query_apdex' => 'empty_result' },
               { 'node_memory' => 'empty_result' },
               { 'node_memory_utilization' => 'empty_result' },
               { 'service_rss' => 'empty_result' },
@@ -245,6 +249,7 @@ RSpec.describe Gitlab::UsageData::Topology do
         it 'normalizes equivalent instance values and maps them to the same node' do
           expect_prometheus_api_to(
             receive_app_request_volume_query(result: []),
+            receive_query_apdex_ratio_query(result: []),
             receive_node_memory_query(result: node_memory_response),
             receive_node_memory_utilization_query(result: node_memory_utilization_response),
             receive_node_cpu_count_query(result: []),
@@ -261,6 +266,7 @@ RSpec.describe Gitlab::UsageData::Topology do
             duration_s: 0,
             failures: [
               { 'app_requests' => 'empty_result' },
+              { 'query_apdex' => 'empty_result' },
               { 'node_cpus' => 'empty_result' },
               { 'node_cpu_utilization' => 'empty_result' },
               { 'service_uss' => 'empty_result' },
@@ -309,6 +315,7 @@ RSpec.describe Gitlab::UsageData::Topology do
         it 'still reports service metrics' do
           expect_prometheus_api_to(
             receive_app_request_volume_query(result: []),
+            receive_query_apdex_ratio_query(result: []),
             receive_node_memory_query(result: []),
             receive_node_memory_utilization_query(result: []),
             receive_node_cpu_count_query(result: []),
@@ -325,6 +332,7 @@ RSpec.describe Gitlab::UsageData::Topology do
             duration_s: 0,
             failures: [
               { 'app_requests' => 'empty_result' },
+              { 'query_apdex' => 'empty_result' },
               { 'node_memory' => 'empty_result' },
               { 'node_memory_utilization' => 'empty_result' },
               { 'node_cpus' => 'empty_result' },
@@ -382,6 +390,7 @@ RSpec.describe Gitlab::UsageData::Topology do
         it 'filters out unknown service data and reports the unknown services as a failure' do
           expect_prometheus_api_to(
             receive_app_request_volume_query(result: []),
+            receive_query_apdex_ratio_query(result: []),
             receive_node_memory_query(result: []),
             receive_node_memory_utilization_query(result: []),
             receive_node_cpu_count_query(result: []),
@@ -412,6 +421,7 @@ RSpec.describe Gitlab::UsageData::Topology do
               duration_s: 0,
               failures: [
                 { 'app_requests' => 'Gitlab::PrometheusClient::ConnectionError' },
+                { 'query_apdex' => 'Gitlab::PrometheusClient::ConnectionError' },
                 { 'node_memory' => 'Gitlab::PrometheusClient::ConnectionError' },
                 { 'node_memory_utilization' => 'Gitlab::PrometheusClient::ConnectionError' },
                 { 'node_cpus' => 'Gitlab::PrometheusClient::ConnectionError' },
@@ -442,6 +452,7 @@ RSpec.describe Gitlab::UsageData::Topology do
                 duration_s: 0,
                 failures: [
                   { 'app_requests' => exception.to_s },
+                  { 'query_apdex' => 'timeout_cancellation' },
                   { 'node_memory' => 'timeout_cancellation' },
                   { 'node_memory_utilization' => 'timeout_cancellation' },
                   { 'node_cpus' => 'timeout_cancellation' },
@@ -497,6 +508,17 @@ RSpec.describe Gitlab::UsageData::Topology do
       ])
   end
 
+  def receive_query_apdex_ratio_query(result: nil)
+    receive(:query)
+      .with(/gitlab_usage_ping:sql_duration_apdex:ratio_rate5m/)
+      .and_return(result || [
+        {
+          'metric' => {},
+          'value' => [1000, '0.996']
+        }
+      ])
+  end
+
   def receive_node_memory_query(result: nil)
     receive(:query)
       .with(/node_memory_total_bytes/, an_instance_of(Hash))