Merge branch 'am-usage-data-add-hostname-metric' into 'master'

Add HostnameMetric in usage data

See merge request gitlab-org/gitlab!60256

config/metrics/license/20210204124827_hostname.yml

@@ -8,7 +8,8 @@ product_category: collection
 value_type: string
 status: data_available
 time_frame: none
-data_source:
+data_source: ruby
+instrumentation_class: 'Gitlab::Usage::Metrics::Instrumentations::HostnameMetric'
 distribution:
 - ce
 - ee

lib/gitlab/usage/metrics/instrumentations/hostname_metric.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Usage
+    module Metrics
+      module Instrumentations
+        class HostnameMetric < GenericMetric
+          value do
+            Gitlab.config.gitlab.host
+          end
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/usage/metrics/instrumentations/hostname_metric_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Usage::Metrics::Instrumentations::HostnameMetric do
+  it_behaves_like 'a correct instrumented metric value', { time_frame: 'none', data_source: 'ruby' }, Gitlab.config.gitlab.host
+end

spec/lib/gitlab/usage_data_metrics_spec.rb

@@ -19,6 +19,7 @@ RSpec.describe Gitlab::UsageDataMetrics do
     context 'whith instrumentation_class' do
       it 'includes top level keys' do
         expect(subject).to include(:uuid)
+        expect(subject).to include(:hostname)
       end
 
       it 'includes counts keys' do