Introduce a class to represent the answer file

Refactors code into an AnswerFile class for handling the loading of
and details of the parts of the answer file. This abstraction will
allow easier introduction of newer versions of the answer file.

README.md

@@ -158,6 +158,32 @@ As you may have noticed there are several ways how to specify arguments. Here's
   * values specified on CLI
   * interactive mode arguments
 
+## Answer File Schema
+
+The answer file schema can be described using Puppet types as such:
+
+```
+Hash[
+  String $puppet_class => Hash[
+    String $parameter => Enum[true, false, Hash[String, Variant[String, Boolean, Integer, Array, Hash]]]
+  ]
+]
+```
+
+An example of each available option:
+
+```
+class_a: true
+class_b: false
+class_c: {}
+class_d:
+  key: value
+  key2: 'value'
+  key3: false
+  key4: 1
+  key5: ['a', 'b']
+```
+
 ## Requirements
 
 Kafo is supported with Puppet versions 4.9+, 5 and 6. Puppet may be installed

lib/kafo/answer_file.rb

@@ -0,0 +1,68 @@
+require 'yaml'
+
+module Kafo
+  class AnswerFile
+
+    attr_reader :answers, :filename, :version
+
+    def initialize(answer_filename, version: 1, exit_handler: KafoConfigure, logger: KafoConfigure.logger)
+      @filename = answer_filename
+      @version = version.nil? ? 1 : version
+      @exit_handler = exit_handler
+      @logger = logger
+
+      begin
+        @answers = YAML.load_file(@filename)
+      rescue Errno::ENOENT
+        @exit_handler.exit(:no_answer_file) do
+          @logger.error "No answer file found at #{@filename}"
+        end
+      end
+
+      validate
+    end
+
+    def filename
+      @filename
+    end
+
+    def puppet_classes
+      @answers.keys.sort
+    end
+
+    def parameters_for_class(puppet_class)
+      if @version == 1
+        params = @answers[puppet_class]
+        params.is_a?(Hash) ? params : {}
+      end
+    end
+
+    def class_enabled?(puppet_class)
+      if @version == 1
+        value = @answers[puppet_class.is_a?(String) ? puppet_class : puppet_class.identifier]
+        !!value || value.is_a?(Hash)
+      end
+    end
+
+    private
+
+    def validate
+      if @version == 1
+        validate_version_1
+      end
+    end
+
+    def validate_version_1
+      invalid = @answers.reject do |puppet_class, value|
+        value.is_a?(Hash) || [true, false].include?(value)
+      end
+
+      unless invalid.empty?
+        @exit_handler.exit(:invalid_values) do
+          @logger.error("Answer file at #{@filename} has invalid values for #{invalid.keys.join(', ')}. Please ensure they are either a hash or true/false.")
+        end
+      end
+    end
+
+  end
+end

lib/kafo/configuration.rb

@@ -6,6 +6,7 @@
 require 'kafo/data_type_parser'
 require 'kafo/execution_environment'
 require 'kafo/scenario_option'
+require 'kafo/answer_file'
 
 module Kafo
   class Configuration
@@ -55,13 +56,8 @@ def initialize(file, persist = true)
       configure_application
       @logger = KafoConfigure.logger
 
-      @answer_file = app[:answer_file]
-      begin
-        @data = load_yaml_file(@answer_file)
-      rescue Errno::ENOENT
-        puts "No answer file at #{@answer_file} found, can not continue"
-        KafoConfigure.exit(:no_answer_file)
-      end
+      @answer_file = AnswerFile.new(app[:answer_file], version: app[:answer_file_version])
+      @answers = @answer_file.answers
 
       @config_dir = File.dirname(@config_file)
       @scenario_id = Configuration.get_scenario_id(@config_file)
@@ -130,7 +126,7 @@ def has_custom_fact?(key)
     def modules
       @modules ||= begin
         register_data_types
-        @data.keys.map { |mod| PuppetModule.new(mod, configuration: self).parse }.sort
+        @answer_file.puppet_classes.map { |mod| PuppetModule.new(mod, configuration: self).parse }.sort
       end
     end
 
@@ -231,14 +227,12 @@ class { '::kafo_configure::dump_values':
 
     # if a value is a true we return empty hash because we have no specific options for a
     # particular puppet module
-    def [](key)
-      value = @data[key]
-      value.is_a?(Hash) ? value : {}
+    def [](puppet_class)
+      @answer_file.parameters_for_class(puppet_class)
     end
 
-    def module_enabled?(mod)
-      value = @data[mod.is_a?(String) ? mod : mod.identifier]
-      !!value || value.is_a?(Hash)
+    def module_enabled?(puppet_class)
+      @answer_file.class_enabled?(puppet_class)
     end
 
     def config_header
@@ -248,7 +242,7 @@ def config_header
     end
 
     def store(data, file = nil)
-      filename = file || answer_file
+      filename = file || @answer_file.filename
       FileUtils.touch filename
       File.chmod 0600, filename
       File.open(filename, 'w') { |f| f.write(config_header + format(YAML.dump(data))) }
@@ -316,17 +310,13 @@ def log_exists?
       log_files.any? { |f| File.size(f) > 0 }
     end
 
-    def answers
-      @data
-    end
-
     def run_migrations
       migrations = Kafo::Migrations.new(migrations_dir)
-      @app, @data = migrations.run(app, answers)
+      @app, @answers = migrations.run(app, @answers)
       if migrations.migrations.count > 0
         @modules = nil # force the lazy loaded modules to reload next time they are used
         save_configuration(app)
-        store(answers)
+        store(@answers)
         migrations.store_applied
         @logger.notice("#{migrations.migrations.count} migration/s were applied. Updated configuration was saved.")
       end

test/fixtures/answer_files/v1/basic-answers.yaml

@@ -0,0 +1,6 @@
+---
+class_a: true
+class_b:
+  key: value
+class_c: {}
+class_d: false

test/fixtures/answer_files/v1/invalid-answers.yaml

@@ -0,0 +1,4 @@
+---
+class_a: 'true'
+class_b:
+class_c: 1

test/kafo/answer_file_test.rb

@@ -0,0 +1,47 @@
+require 'test_helper'
+
+describe 'Kafo::AnswerFile' do
+  let(:dummy_logger) { DummyLogger.new }
+
+  describe 'answer file version 1' do
+    describe 'valid answer file' do
+      let(:answer_file_path) { 'test/fixtures/answer_files/v1/basic-answers.yaml' }
+      let(:answer_file) { Kafo::AnswerFile.new(answer_file_path) }
+
+      it 'returns the sorted puppet classes' do
+        _(answer_file.puppet_classes).must_equal(['class_a', 'class_b', 'class_c', 'class_d'])
+      end
+
+      it 'returns the parameters for a class' do
+        _(answer_file.parameters_for_class('class_b')).must_equal({'key' => 'value'})
+      end
+
+      it 'returns true for a class with a hash' do
+        _(answer_file.class_enabled?('class_c')).must_equal(true)
+      end
+
+      it 'returns true for a class set to true' do
+        _(answer_file.class_enabled?('class_a')).must_equal(true)
+      end
+
+      it 'returns false for a class set to false' do
+        _(answer_file.class_enabled?('class_d')).must_equal(false)
+      end
+    end
+
+    describe 'invalid answer file' do
+      let(:answer_file_path) { 'test/fixtures/answer_files/v1/invalid-answers.yaml' }
+
+      before do
+        Kafo::KafoConfigure.logger = dummy_logger
+      end
+
+      it 'exits with invalid_answer_file' do
+        must_exit_with_code(21) { Kafo::AnswerFile.new(answer_file_path) }
+
+        dummy_logger.rewind
+        _(dummy_logger.error.read).must_match(%r{Answer file at test/fixtures/answer_files/v1/invalid-answers.yaml has invalid values for class_a, class_b, class_c. Please ensure they are either a hash or true/false.\n})
+      end
+    end
+  end
+end