Add git push counter to geo node status

On geo secondaries, we'd like to collect and transmit
usage ping data about git operations.
That includs pushes and pulls.

Changelog: changed
EE: true

doc/development/usage_ping/dictionary.md

@@ -16260,6 +16260,18 @@ Status: `data_available`
 
 Tiers: `premium`, `ultimate`
 
+### `usage_activity_by_stage.enablement.counts.geo_node_usage.git_push_event_count_weekly`
+
+Number of Git push events from Prometheus on the Geo secondary
+
+[YAML definition](https://gitlab.com/gitlab-org/gitlab/-/blob/master/ee/config/metrics/counts_7d/20210604110603_git_push_event_count_weekly.yml)
+
+Group: `group::geo`
+
+Status: `data_available`
+
+Tiers: `premium`, `ultimate`
+
 ### `usage_activity_by_stage.enablement.geo_secondary_web_oauth_users`
 
 Missing description

ee/app/models/geo/secondary_usage_data.rb

@@ -6,6 +6,7 @@ class Geo::SecondaryUsageData < Geo::TrackingBase
   include Gitlab::Utils::UsageData
 
   GIT_FETCH_EVENT_COUNT_WEEKLY_QUERY = 'round(sum(increase(grpc_server_handled_total{grpc_method=~"SSHUploadPack|PostUploadPack"}[7d])))'
+  GIT_PUSH_EVENT_COUNT_WEEKLY_QUERY = 'round(sum(increase(grpc_server_handled_total{grpc_method=~"SSHReceivePack|PostReceivePack"}[7d])))'
 
   # Eventually, we'll find a way to auto-load this
   # from the metric yaml files that include something
@@ -13,6 +14,7 @@ class Geo::SecondaryUsageData < Geo::TrackingBase
   # just enumerate them.
   PAYLOAD_COUNT_FIELDS = %w(
     git_fetch_event_count_weekly
+    git_push_event_count_weekly
   ).freeze
 
   store_accessor :payload, *PAYLOAD_COUNT_FIELDS
@@ -35,8 +37,9 @@ class Geo::SecondaryUsageData < Geo::TrackingBase
   end
 
   def collect_prometheus_metrics
-    self.git_fetch_event_count_weekly = with_prometheus_client(fallback: nil, verify: false) do |client|
-      client.query(GIT_FETCH_EVENT_COUNT_WEEKLY_QUERY).dig(0, "value", 1)&.to_i
+    with_prometheus_client(fallback: nil, verify: false) do |client|
+      self.git_fetch_event_count_weekly = client.query(GIT_FETCH_EVENT_COUNT_WEEKLY_QUERY).dig(0, "value", 1)&.to_i
+      self.git_push_event_count_weekly = client.query(GIT_PUSH_EVENT_COUNT_WEEKLY_QUERY).dig(0, "value", 1)&.to_i
     end
   end
 end

ee/config/metrics/counts_7d/20210604110603_git_push_event_count_weekly.yml

+---
+key_path: usage_activity_by_stage.enablement.counts.geo_node_usage.git_push_event_count_weekly
+description: Number of git push events from Prometheus on the Geo secondary
+product_section: enablement
+product_stage: enablement
+product_group: group::geo
+product_category: geo_replication
+value_type: number
+status: data_available
+milestone: "14.0"
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/63427/
+time_frame: 7d
+data_source: prometheus
+distribution:
+  - ee
+tier:
+ - premium
+ - ultimate

ee/spec/fixtures/api/schemas/public_api/v4/geo_node_status.json

@@ -146,6 +146,7 @@
     "replication_slots_used_in_percentage",
     "replication_slots_max_retained_wal_bytes",
     "git_fetch_event_count_weekly",
+    "git_push_event_count_weekly",
     "last_event_id",
     "last_event_timestamp",
     "cursor_last_event_id",
@@ -311,6 +312,7 @@
     "replication_slots_used_in_percentage": { "type": "string" },
     "replication_slots_max_retained_wal_bytes": { "type": ["integer", "null"] },
     "git_fetch_event_count_weekly": { "type": ["integer", "null"] },
+    "git_push_event_count_weekly": { "type": ["integer", "null"] },
     "last_event_id": { "type": ["integer", "null"] },
     "last_event_timestamp": { "type": ["integer", "null"] },
     "cursor_last_event_id": { "type": ["integer", "null"] },

ee/spec/models/geo/secondary_usage_data_spec.rb

@@ -50,6 +50,8 @@ RSpec.describe Geo::SecondaryUsageData, :geo, type: :model do
       allow_next_instance_of(described_class) do |instance|
         allow(instance).to receive(:with_prometheus_client).and_yield(prometheus_client)
       end
+
+      allow(prometheus_client).to receive(:query).and_return([])
     end
 
     context 'metric git_fetch_event_count_weekly' do
@@ -66,7 +68,7 @@ RSpec.describe Geo::SecondaryUsageData, :geo, type: :model do
       end
 
       it 'returns nil if metric is unavailable' do
-        expect(prometheus_client).to receive(:query).with(Geo::SecondaryUsageData::GIT_FETCH_EVENT_COUNT_WEEKLY_QUERY).and_return([])
+        allow(prometheus_client).to receive(:query).with(Geo::SecondaryUsageData::GIT_FETCH_EVENT_COUNT_WEEKLY_QUERY).and_return([])
 
         expect do
           described_class.update_metrics!
@@ -89,5 +91,43 @@ RSpec.describe Geo::SecondaryUsageData, :geo, type: :model do
         expect(described_class.last.git_fetch_event_count_weekly).to be_nil
       end
     end
+
+    context 'metric git_push_event_count_weekly' do
+      it 'gets metrics from prometheus' do
+        expected_result = 48
+        allow(prometheus_client).to receive(:query).with(Geo::SecondaryUsageData::GIT_PUSH_EVENT_COUNT_WEEKLY_QUERY).and_return([{ "value" => [1614029769.82, expected_result.to_s] }])
+
+        expect do
+          described_class.update_metrics!
+        end.to change { described_class.count }.by(1)
+
+        expect(described_class.last).to be_valid
+        expect(described_class.last.git_push_event_count_weekly).to eq(expected_result)
+      end
+
+      it 'returns nil if metric is unavailable' do
+        allow(prometheus_client).to receive(:query).with(Geo::SecondaryUsageData::GIT_PUSH_EVENT_COUNT_WEEKLY_QUERY).and_return([])
+
+        expect do
+          described_class.update_metrics!
+        end.to change { described_class.count }.by(1)
+
+        expect(described_class.last).to be_valid
+        expect(described_class.last.git_push_event_count_weekly).to be_nil
+      end
+
+      it 'returns nil if it cannot reach prometheus' do
+        expect_next_instance_of(described_class) do |instance|
+          expect(instance).to receive(:with_prometheus_client).and_return(nil)
+        end
+
+        expect do
+          described_class.update_metrics!
+        end.to change { described_class.count }.by(1)
+
+        expect(described_class.last).to be_valid
+        expect(described_class.last.git_push_event_count_weekly).to be_nil
+      end
+    end
   end
 end