Add metric name suggestion generator

lib/gitlab/usage/metrics/names_suggestions/generator.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Usage
+    module Metrics
+      module NamesSuggestions
+        class Generator < ::Gitlab::UsageData
+          class << self
+            def generate(key_path)
+              uncached_data.deep_stringify_keys.dig(*key_path.split('.'))
+            end
+
+            private
+
+            def count(relation, column = nil, batch: true, batch_size: nil, start: nil, finish: nil)
+              "count_#{parse_target_and_source(column, relation)}"
+            end
+
+            def distinct_count(relation, column = nil, batch: true, batch_size: nil, start: nil, finish: nil)
+              "count_distinct_#{parse_target_and_source(column, relation)}"
+            end
+
+            def redis_usage_counter
+              "names_suggestions_for_redis_counters_are_not_supported_yet"
+            end
+
+            def redis_usage_data_totals(counter)
+              counter.fallback_totals.transform_values { |_| "names_suggestions_for_redis_counters_are_not_supported_yet" }
+            end
+
+            def sum(relation, column, *rest)
+              "sum_#{parse_target_and_source(column, relation)}"
+            end
+
+            def estimate_batch_distinct_count(relation, column = nil, *rest)
+              "estimate_distinct_#{parse_target_and_source(column, relation)}"
+            end
+
+            def add(*args)
+              "add_#{args.join('_and_')}"
+            end
+
+
+            def parse_target_and_source(column, relation)
+              if column
+                "#{column}_from_#{relation.table_name}"
+              else
+                relation.table_name
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/usage/metrics/names_suggestions/generator_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::Usage::Metrics::NamesSuggestions::Generator do
+  describe '#generate' do
+    context 'for count metrics' do
+      it 'return correct name' do
+        expect(described_class.generate('counts.boards')).to eq 'count_boards'
+      end
+    end
+
+    context 'for count distinct metrics' do
+      it 'return correct name' do
+        expect(described_class.generate('counts.issues_using_zoom_quick_actions')).to eq 'count_distinct_issue_id_from_zoom_meetings'
+      end
+    end
+
+    context 'for sum metrics' do
+      it 'return correct name' do
+        expect(described_class.generate('counts.jira_imports_total_imported_issues_count')).to eq 'sum_imported_issues_count_from_jira_imports'
+      end
+    end
+
+    context 'for add metrics' do
+      it 'return correct name' do
+        expect(described_class.generate('counts.snippets')).to eq 'add_count_snippets_and_count_snippets'
+      end
+    end
+
+    context 'for redis metrics' do
+      it 'return correct name' do
+        expect(described_class.generate('analytics_unique_visits.analytics_unique_visits_for_any_target')).to eq 'names_suggestions_for_redis_counters_are_not_supported_yet'
+      end
+    end
+  end
+end