Add specs for PatroniHelper

Add coverage for existing features and changes related to the standby cluster

spec/chef/patroni/libraries/patroni_helper_spec.rb

+require 'chef_helper'
+
+RSpec.describe PatroniHelper do
+  let(:chef_run) do
+    ChefSpec::SoloRunner.new(step_into: %w(patroni)).converge('gitlab-ee::default')
+  end
+
+  subject(:helper) { PatroniHelper.new(chef_run.node) }
+
+  before do
+    allow(Gitlab).to receive(:[]).and_call_original
+  end
+
+  describe '#ctl_command' do
+    it 'returns a full path to the ctl_command' do
+      expect(helper.ctl_command).to eq('/opt/gitlab/embedded/bin/patronictl')
+    end
+  end
+
+  describe '#bootstrapped?' do
+    before do
+      allow(File).to receive(:exist?).and_call_original
+    end
+
+    it 'returns true when patroni.dynamic.json exists in postgresql data directory' do
+      allow(File).to receive(:exist?).with('/var/opt/gitlab/postgresql/data/patroni.dynamic.json').and_return(true)
+
+      expect(helper.bootstrapped?).to eq(true)
+    end
+
+    it 'returns false when patroni.dynamic.json does not exist in postgresql data directory' do
+      allow(File).to receive(:exist?).with('/var/opt/gitlab/postgresql/data/patroni.dynamic.json').and_return(false)
+
+      expect(helper.bootstrapped?).to eq(false)
+    end
+  end
+
+  describe '#dynamic_settings' do
+    it 'returns a hash with required keys' do
+      expected_root_keys = PatroniHelper::DCS_ATTRIBUTES + %w[postgresql slots]
+
+      expect(helper.dynamic_settings.keys).to match_array(expected_root_keys)
+    end
+
+    context 'with standby cluster enabled' do
+      it 'includes standby cluster attributes' do
+        stub_gitlab_rb(
+          patroni: {
+            enable: true,
+            standby_cluster: {
+              enable: true
+            }
+          }
+        )
+
+        expected_root_keys = PatroniHelper::DCS_ATTRIBUTES + %w[postgresql slots standby_cluster]
+
+        expect(helper.dynamic_settings.keys).to match_array(expected_root_keys)
+      end
+    end
+  end
+
+  describe '#public_attributes' do
+    context 'when patroni is enabled' do
+      it 'returns a hash with required keys' do
+        stub_gitlab_rb(
+          patroni: {
+            enable: true
+          }
+        )
+
+        expected_patroni_keys = %w(config_dir data_dir log_dir api_address)
+
+        expect(helper.public_attributes.keys).to match_array('patroni')
+        expect(helper.public_attributes['patroni'].keys).to match_array(expected_patroni_keys)
+      end
+    end
+
+    context 'when patroni is disabled' do
+      it 'returns an empty hash' do
+        expect(helper.public_attributes).to be_empty
+      end
+    end
+  end
+end