Merge branch 'network-policy-usage-counter' into 'master'

Add usage data counter for network policy packet stats

See merge request gitlab-org/gitlab!30005

ee/lib/gitlab/usage_data_counters/network_policy_counter.rb

+# frozen_string_literal: true
+
+module Gitlab::UsageDataCounters
+  class NetworkPolicyCounter < BaseCounter
+    KNOWN_EVENTS = %w[forwards drops].freeze
+    PREFIX = 'network_policy'
+
+    class << self
+      def add(forwards, drops)
+        return unless Gitlab::CurrentSettings.usage_ping_enabled?
+
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.multi do
+            redis.incrby(redis_key(:forwards), forwards)
+            redis.incrby(redis_key(:drops), drops)
+          end
+        end
+      end
+    end
+  end
+end

ee/spec/lib/gitlab/usage_data_counters/network_policy_counter_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::UsageDataCounters::NetworkPolicyCounter, :clean_gitlab_redis_shared_state do
+  describe '.add' do
+    it 'increases drops and forwards counters' do
+      described_class.add(10, 5)
+      expect(described_class.totals).to eq(network_policy_forwards: 10, network_policy_drops: 5)
+
+      described_class.add(2, 1)
+      expect(described_class.totals).to eq(network_policy_forwards: 12, network_policy_drops: 6)
+    end
+  end
+end