Add Customer Success::Impact Check label when metric category changes

danger/customer_success/Dangerfile

+# frozen_string_literal: true
+
+markdown(customer_success.build_message)

danger/plugins/customer_success.rb

+# frozen_string_literal: true
+
+require_relative '../../tooling/danger/customer_success'
+
+module Danger
+  class CustomerSuccess < ::Danger::Plugin
+    include Tooling::Danger::CustomerSuccess
+  end
+end

spec/tooling/danger/customer_success_spec.rb

+# frozen_string_literal: true
+
+require 'rspec-parameterized'
+require 'gitlab-dangerfiles'
+require 'gitlab/dangerfiles/spec_helper'
+require_relative '../../../tooling/danger/customer_success'
+
+RSpec.describe Tooling::Danger::CustomerSuccess do
+  include_context "with dangerfile"
+
+  let(:fake_danger) { DangerSpecHelper.fake_danger.include(described_class) }
+  let(:customer_success) { fake_danger.new(helper: fake_helper) }
+
+  describe 'customer success danger' do
+    using RSpec::Parameterized::TableSyntax
+
+    where do
+      {
+        'with data category changes to Ops and no Customer Success::Impact Check label' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml app/models/user.rb),
+          changed_lines: ['-data_category: cat1', '+data_category: operational'],
+          customer_labeled: false,
+          impacted: true,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        },
+        'with data category changes and Customer Success::Impact Check label' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml),
+          changed_lines: ['-data_category: cat1', '+data_category: operational'],
+          customer_labeled: true,
+          impacted: false,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        },
+        'with metric file changes and no data category changes' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml),
+          changed_lines: ['-product_stage: growth'],
+          customer_labeled: false,
+          impacted: false,
+          impacted_files: []
+        },
+        'with data category changes from Ops' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml app/models/user.rb),
+          changed_lines: ['-data_category: operational', '+data_category: cat2'],
+          customer_labeled: false,
+          impacted: true,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        },
+        'with data category removed' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml app/models/user.rb),
+          changed_lines: ['-data_category: operational'],
+          customer_labeled: false,
+          impacted: true,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        },
+        'with data category added' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml app/models/user.rb),
+          changed_lines: ['+data_category: operational'],
+          customer_labeled: false,
+          impacted: true,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        },
+        'with data category in uppercase' => {
+          modified_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml app/models/user.rb),
+          changed_lines: ['+data_category: Operational'],
+          customer_labeled: false,
+          impacted: true,
+          impacted_files: %w(config/metrics/20210216182127_user_secret_detection_jobs.yml)
+        }
+      }
+    end
+
+    with_them do
+      before do
+        allow(fake_helper).to receive(:modified_files).and_return(modified_files)
+        allow(fake_helper).to receive(:changed_lines).and_return(changed_lines)
+        allow(fake_helper).to receive(:has_scoped_label_with_scope?).and_return(customer_labeled)
+        allow(fake_helper).to receive(:markdown_list).with(impacted_files)
+                                .and_return(impacted_files.map { |item| "* `#{item}`" }.join("\n"))
+      end
+
+      it 'generates correct message' do
+        expect(customer_success.build_message).to match_expected_message
+      end
+    end
+  end
+
+  def match_expected_message
+    return be_nil unless impacted
+
+    start_with(described_class::CHANGED_SCHEMA_MESSAGE).and(include(*impacted_files))
+  end
+end

tooling/danger/customer_success.rb

+# frozen_string_literal: true
+
+module Tooling
+  module Danger
+    module CustomerSuccess
+      CHANGED_SCHEMA_MESSAGE = <<~MSG
+        Notification to the Customer Success about changes to files with possible breaking downstream processes, add label `Customer Success::Impact Check`.
+
+        /label ~"Customer Success::Impact Check"
+
+        The following files require a review:
+      MSG
+
+      FILE_PATH_REGEX = %r{((ee|jh)/)?config/metrics/.+\.yml}.freeze
+      CATEGORY_CHANGED = /data_category: operational/i.freeze
+
+      def build_message
+        return unless impacted?
+
+        CHANGED_SCHEMA_MESSAGE + helper.markdown_list(impacted_files)
+      end
+
+      private
+
+      def impacted?
+        !helper.has_scoped_label_with_scope?('Customer Success') && impacted_files.any?
+      end
+
+      def impacted_files
+        @impacted_files ||=
+          metric_files.select do |file|
+            helper.changed_lines(file).any? { |change| metric_category_changed?(change) }
+          end.compact
+      end
+
+      def metric_files
+        helper.modified_files.grep(FILE_PATH_REGEX)
+      end
+
+      def metric_category_changed?(change)
+        change =~ CATEGORY_CHANGED
+      end
+    end
+  end
+end