Set up SpamAssassin

Scan incoming and outgoing email for spam. Use a local Unbound for DNS,
so we don't run into blocks for RBL queries.

cookbooks/unbound/resources/service.rb

@@ -0,0 +1,69 @@
+#
+# Cookbook:: unbound
+# Resource:: service
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+unified_mode true
+
+property :service_name, String,
+          default: 'unbound',
+          description: 'The service name to perform actions upon'
+
+property :config_test, [true, false],
+          default: true,
+          description: 'Perform configuration file test before performing service action'
+
+property :config_test_fail_action, Symbol,
+          equal_to: %i(raise log),
+          default: :raise,
+          description: 'Action to perform upon configuration test failure.'
+
+action_class do
+  def perform_config_test
+    cmd = shell_out('/usr/sbin/unbound-checkconf')
+    cmd.error!
+  rescue Mixlib::ShellOut::ShellCommandFailed
+    if new_resource.config_test_fail_action.eql?(:log)
+      Chef::Log.error("Configuration test failed, #{new_resource.service_name} #{action} action aborted!\n\n"\
+                      "Error\n-----\n#{cmd.stderr}")
+    else
+      raise "Configuration test failed, #{new_resource.service_name} #{action} action aborted!\n\n"\
+            "Error\n-----\nAction: #{action}\n#{cmd.stderr}"
+    end
+  end
+
+  def do_service_action(service_action)
+    with_run_context(:root) do
+      if %i(start restart reload).include?(service_action)
+        if new_resource.config_test
+          perform_config_test
+          Chef::Log.info("Configuration test passed, creating #{new_resource.service_name} #{new_resource.declared_type} resource with action #{service_action}")
+        else
+          Chef::Log.info("Configuration test disabled, creating #{new_resource.service_name} #{new_resource.declared_type} resource with action #{service_action}")
+        end
+
+        declare_resource(:service, new_resource.service_name) { delayed_action(service_action) }
+      else
+        declare_resource(:service, new_resource.service_name) { action(service_action) }
+      end
+    end
+  end
+end
+
+%i(start stop restart reload enable disable).each { |action_type| action(action_type) { do_service_action(action_type) } }
+
+action :test do
+  converge_by('Performing configuration test') { perform_config_test }
+end