Support dotted-path sub-fact selection in facts_allowlist

lib/puppet/indirector/facts/splunk_hec.rb

@@ -60,7 +60,26 @@ def save(request)
                 final_block = block_list.reject { |k| hardcoded.include?(k) }
                 incoming_facts.reject { |k, _v| final_block.include?(k) }
               else
-                incoming_facts.select { |k, _v| allow_list.include?(k) }
+                selected = {}
+
+                allow_list.each do |path|
+                  parts    = path.split('.')
+                  top_key  = parts.first
+                  sub_keys = parts[1..]
+
+                  value = incoming_facts.dig(*parts)
+                  next if value.nil?
+
+                  nested = sub_keys.reverse.reduce(value) { |acc, k| { k => acc } }
+
+                  selected[top_key] = if selected.key?(top_key) && selected[top_key].is_a?(Hash)
+                                        selected[top_key].merge(nested)
+                                      else
+                                        nested
+                                      end
+                end
+
+                selected
               end
 
       facts['trusted'] = get_trusted_info(request.node)

manifests/init.pp

@@ -10,6 +10,7 @@
 #   Note: The value of the token is converted to Puppet's Sensitive data type during catalog application.
 # @param [Array] facts_allowlist
 #   The list of facts that will be collected in the report. To collect all facts available add the special value 'all.facts'.
+#   Individual sub-keys of structured facts can be selected using dot-notation (e.g. 'networking.ip' instead of the full 'networking' fact).
 # @param [Boolean] enable_reports
 #   Adds splunk_hec to the list of report processors
 # @param [Boolean] record_event

spec/unit/indirector/facts/splunk_hec_spec.rb

@@ -0,0 +1,170 @@
+require 'spec_helper'
+require 'puppet/node/facts'
+require 'puppet/indirector/facts/splunk_hec'
+
+describe Puppet::Node::Facts::Splunk_hec do
+  subject(:indirector) { described_class.new }
+
+  let(:settings_hash) do
+    {
+      'url'             => 'https://splunk.example.com',
+      'facts.allowlist' => ['os', 'networking'],
+      'facts.blocklist' => nil,
+    }
+  end
+
+  let(:incoming_facts) do
+    {
+      'os'         => { 'family' => 'RedHat', 'release' => { 'major' => '7' } },
+      'networking' => { 'ip' => '10.0.0.1', 'mac' => 'AA:BB:CC:DD:EE:FF', 'interfaces' => { 'eth0' => { 'ip' => '10.0.0.1' } } },
+      'secret'     => 'should not appear',
+      'ipaddress'  => '10.0.0.1',
+      'fqdn'       => 'node.example.com',
+    }
+  end
+
+  let(:node_name) { 'node.example.com' }
+
+  # Build a minimal facts indirector request double
+  let(:request) do
+    facts_obj = instance_double('Puppet::Node::Facts')
+    allow(facts_obj).to receive(:name).and_return(node_name)
+    allow(facts_obj).to receive(:values).and_return(incoming_facts)
+
+    req = instance_double('Puppet::Indirector::Request')
+    allow(req).to receive(:instance).and_return(facts_obj)
+    allow(req).to receive(:key).and_return(node_name)
+    allow(req).to receive(:node).and_return(node_name)
+    allow(req).to receive(:options).and_return({ transaction_uuid: 'abc-123', environment: 'production' })
+    allow(req).to receive(:environment).and_return('production')
+    req
+  end
+
+  before(:each) do
+    allow(YAML).to receive(:load_file).with(%r{settings\.yaml}).and_return(settings_hash)
+    allow(YAML).to receive(:load_file).with(%r{hec_secrets\.yaml}).and_return({ 'token' => 'test-token' })
+
+    # Skip the yaml-cache super call
+    allow_any_instance_of(Puppet::Node::Facts::Yaml).to receive(:save)
+
+    # profile's arity check can fall through in newer Puppet versions, leaving the
+    # block uncalled. Stub it to always yield so the save logic actually runs.
+    allow(indirector).to receive(:profile).and_yield
+
+    allow(indirector).to receive(:get_trusted_info).and_return({ 'authenticated' => 'remote' })
+    allow(indirector).to receive(:submit_request)
+    allow(indirector).to receive(:get_splunk_url).and_return('https://splunk.example.com/services/collector')
+
+    # Surface any errors that would otherwise be silently swallowed by the rescue block
+    allow(Puppet).to receive(:err) { |msg| raise msg }
+    allow(Puppet).to receive(:info)
+  end
+
+  def submitted_event
+    captured = nil
+    allow(indirector).to receive(:submit_request) { |event| captured = event }
+    indirector.save(request)
+    captured
+  end
+
+  context 'allowlist filtering' do
+    context 'with top-level fact names' do
+      it 'includes allowlisted facts' do
+        event = submitted_event
+        expect(event['event']).to include('os', 'networking')
+      end
+
+      it 'excludes facts not in the allowlist' do
+        event = submitted_event
+        expect(event['event']).not_to have_key('secret')
+      end
+
+      it 'includes hardcoded facts regardless of allowlist' do
+        event = submitted_event
+        expect(event['event']).to include('ipaddress', 'fqdn')
+      end
+    end
+
+    context 'with dotted-path entries' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['networking.ip']) }
+
+      it 'includes only the specified sub-key' do
+        event = submitted_event
+        expect(event['event']['networking']).to eq({ 'ip' => '10.0.0.1' })
+      end
+
+      it 'excludes unspecified sibling keys' do
+        event = submitted_event
+        expect(event['event']['networking']).not_to have_key('mac')
+        expect(event['event']['networking']).not_to have_key('interfaces')
+      end
+    end
+
+    context 'with multiple dotted-path entries under the same top-level key' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['networking.ip', 'networking.mac']) }
+
+      it 'merges both sub-keys under the shared top-level key' do
+        event = submitted_event
+        expect(event['event']['networking']).to eq({ 'ip' => '10.0.0.1', 'mac' => 'AA:BB:CC:DD:EE:FF' })
+      end
+    end
+
+    context 'with a deeper dotted path' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['networking.interfaces.eth0']) }
+
+      it 'extracts the deeply nested value' do
+        event = submitted_event
+        expect(event['event']['networking']).to eq({ 'interfaces' => { 'eth0' => { 'ip' => '10.0.0.1' } } })
+      end
+    end
+
+    context 'with a dotted path that does not exist in the facts' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['networking.nonexistent']) }
+
+      it 'omits the entry without raising an error' do
+        event = submitted_event
+        expect(event['event']).not_to have_key('networking')
+      end
+    end
+
+    context 'with all.facts' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['all.facts']) }
+
+      it 'includes all facts' do
+        event = submitted_event
+        expect(event['event']).to include('os', 'networking', 'secret', 'ipaddress', 'fqdn')
+      end
+    end
+
+    context 'with all.facts and a blocklist' do
+      let(:settings_hash) { super().merge('facts.allowlist' => ['all.facts'], 'facts.blocklist' => ['secret']) }
+
+      it 'excludes blocklisted facts' do
+        event = submitted_event
+        expect(event['event']).not_to have_key('secret')
+      end
+
+      it 'still includes non-blocklisted facts' do
+        event = submitted_event
+        expect(event['event']).to include('os', 'networking')
+      end
+    end
+  end
+
+  context 'event structure' do
+    it 'sets the correct sourcetype' do
+      event = submitted_event
+      expect(event['sourcetype']).to eq('puppet:facts')
+    end
+
+    it 'sets the host to the node name' do
+      event = submitted_event
+      expect(event['host']).to eq(node_name)
+    end
+
+    it 'includes producer, environment, and transaction_uuid in the event payload' do
+      event = submitted_event
+      expect(event['event']).to include('producer', 'environment', 'transaction_uuid')
+    end
+  end
+end