(PUP-11654) Omit unchanged resources from reports

Before this change, the report contained detailed information
for each resource, regardless if there was a change or not
during catalog application. With this change, the report can
omit unchanged resources from the report by setting
`exclude_unchanged_resources` to true.

Author: tvpartytonight

lib/puppet/defaults.rb

@@ -1450,6 +1450,12 @@ def self.initialize_default_settings!(settings)
 
         To turn off reports entirely, set this to `none`",
     },
+    :exclude_unchanged_resources => {
+      :default => false,
+      :type => :boolean,
+      :desc => 'When set to true, resources that have had no changes after catalog application
+        will not have corresponding unchanged resource status updates listed in the report.'
+    },
     :reportdir => {
       :default => "$vardir/reports",
       :type => :directory,

lib/puppet/transaction/report.rb

@@ -308,6 +308,16 @@ def initialize_from_hash(data)
     end
   end
 
+  def skip_or_to_data_hash(rs)
+    if rs.nil?
+      nil
+    elsif !rs.out_of_sync? && Puppet[:exclude_unchanged_resources]
+      {}
+    else
+      rs.to_data_hash
+    end
+  end
+
   def to_data_hash
     hash = {
       'host' => @host,
@@ -323,7 +333,7 @@ def to_data_hash
       'environment' => @environment,
       'logs' => @logs.map { |log| log.to_data_hash },
       'metrics' => Hash[@metrics.map { |key, metric| [key, metric.to_data_hash] }],
-      'resource_statuses' => Hash[@resource_statuses.map { |key, rs| [key, rs.nil? ? nil : rs.to_data_hash] }],
+      'resource_statuses' => Hash[@resource_statuses.map { |key, rs| [key, skip_or_to_data_hash(rs)] }],
       'corrective_change' => @corrective_change,
     }
 

spec/unit/transaction/report_spec.rb

@@ -1,12 +1,13 @@
 require 'spec_helper'
-
+require 'puppet_spec/compiler'
 require 'puppet'
 require 'puppet/transaction/report'
 require 'matchers/json'
 
 describe Puppet::Transaction::Report do
   include JSONMatchers
   include PuppetSpec::Files
+  include PuppetSpec::Compiler
 
   before do
     allow(Puppet::Util::Storage).to receive(:store)
@@ -136,6 +137,33 @@
     expect(report.metrics['time'].values.any? {|metric| metric.first =~ /whit/i}).to be_falsey
   end
 
+  describe "when exclude_unchanged_resources is true" do
+    before do
+      Puppet[:exclude_unchanged_resources] = true
+    end
+
+    let(:test_dir) { tmpdir('unchanged_resources') }
+    def generate_report_and_get_resource_statuses(test_dir)
+      transaction = apply_compiled_manifest(<<-END)
+        file { '#{test_dir}':
+          ensure => directory
+        }
+      END
+      return transaction.report.to_data_hash['resource_statuses']
+    end
+
+    it 'a changed resource is still reported correctly' do
+      FileUtils.rm_rf(test_dir)
+      resource_statuses = generate_report_and_get_resource_statuses(test_dir)
+      expect(resource_statuses["File[#{test_dir}]"]['out_of_sync']).to be_truthy
+    end
+
+    it 'the status for the unchanged resource should be empty' do
+      resource_statuses = generate_report_and_get_resource_statuses(test_dir)
+      expect(resource_statuses["File[#{test_dir}]"]).to eq({})
+    end
+  end
+
   describe "when accepting logs" do
     before do
       @report = Puppet::Transaction::Report.new