(PDK-506) pdk new provider

This implements `pdk new provider` command to support use of the Resource
API in modules.

This requires the template changes from puppetlabs/pdk-templates#13

See the README on https://github.com/puppetlabs/puppet-resource_api for details

lib/pdk/cli/new.rb

@@ -13,4 +13,5 @@ module PDK::CLI
 require 'pdk/cli/new/class'
 require 'pdk/cli/new/defined_type'
 require 'pdk/cli/new/module'
+require 'pdk/cli/new/provider'
 require 'pdk/cli/new/task'

lib/pdk/cli/new/provider.rb

@@ -0,0 +1,30 @@
+module PDK::CLI
+  @new_provider_cmd = @new_cmd.define_command do
+    name 'provider'
+    usage _('provider [options] <name>')
+    summary _('[experimental] Create a new ruby provider named <name> using given options')
+
+    PDK::CLI.template_url_option(self)
+
+    run do |opts, args, _cmd|
+      PDK::CLI::Util.ensure_in_module!(
+        message: _('Providers can only be created from inside a valid module directory.'),
+        log_level: :info,
+      )
+
+      provider_name = args[0]
+      module_dir = Dir.pwd
+
+      if provider_name.nil? || provider_name.empty?
+        puts command.help
+        exit 1
+      end
+
+      unless Util::OptionValidator.valid_provider_name?(provider_name)
+        raise PDK::CLI::ExitWithError, _("'%{name}' is not a valid provider name") % { name: defined_type_name }
+      end
+
+      PDK::Generate::Provider.new(module_dir, provider_name, opts).run
+    end
+  end
+end

lib/pdk/cli/util/option_validator.rb

@@ -24,6 +24,10 @@ def self.valid_module_name?(string)
         end
         singleton_class.send(:alias_method, :valid_task_name?, :valid_module_name?)
 
+        # https://puppet.com/docs/puppet/5.3/custom_types.html#creating-a-type only says the name has to be a ruby symbol.
+        # Let's assume that only strings similar to module names can actually be resolved by the puppet language.
+        singleton_class.send(:alias_method, :valid_provider_name?, :valid_module_name?)
+
         # Validate a Puppet namespace against the regular expression in the
         # documentation: https://docs.puppet.com/puppet/4.10/lang_reserved.html#classes-and-defined-resource-types
         def self.valid_namespace?(string)

lib/pdk/generate.rb

@@ -1,5 +1,6 @@
-require 'pdk/generate/module'
 require 'pdk/generate/defined_type'
+require 'pdk/generate/module'
+require 'pdk/generate/provider'
 require 'pdk/generate/puppet_class'
 require 'pdk/generate/task'
 require 'pdk/module/metadata'

lib/pdk/generate/provider.rb

@@ -0,0 +1,47 @@
+require 'pdk/generate/puppet_object'
+
+module PDK
+  module Generate
+    class Provider < PuppetObject
+      OBJECT_TYPE = :provider
+
+      # Prepares the data needed to render the new defined type template.
+      #
+      # @return [Hash{Symbol => Object}] a hash of information that will be
+      # provided to the defined type and defined type spec templates during
+      # rendering.
+      def template_data
+        data = {
+          name: object_name,
+          provider_class: Provider.class_name_from_object_name(object_name),
+        }
+
+        data
+      end
+
+      # @return [String] the path where the new type will be written.
+      def target_object_path
+        @target_object_path ||= File.join(module_dir, 'lib', 'puppet', 'type', object_name) + '.rb'
+      end
+
+      # @return [String] the path where the new provider will be written.
+      def target_addon_path
+        @target_addon_path ||= File.join(module_dir, 'lib', 'puppet', 'provider', object_name, object_name) + '.rb'
+      end
+
+      # Calculates the path to the file where the tests for the new defined
+      # type will be written.
+      #
+      # @return [String] the path where the tests for the new defined type
+      # will be written.
+      def target_spec_path
+        @target_spec_path ||= File.join(module_dir, 'spec', 'unit', 'puppet', 'provider', object_name, object_name) + '_spec.rb'
+      end
+
+      # transform a object name into a ruby class name
+      def self.class_name_from_object_name(object_name)
+        object_name.to_s.split('_').map(&:capitalize).join
+      end
+    end
+  end
+end

lib/pdk/generate/puppet_object.rb

@@ -58,6 +58,14 @@ def target_object_path
         raise NotImplementedError
       end
 
+      # @abstract Subclass and implement {#target_addon_path}. Implementations
+      #   of this method should return a String containing the destination path
+      #   of the additional object file being generated.
+      # @return [String] returns nil if there is no additional object file
+      def target_addon_path
+        return nil
+      end
+
       # @abstract Subclass and implement {#target_spec_path}. Implementations
       #   of this method should return a String containing the destination path
       #   of the tests for the object being generated.
@@ -85,7 +93,7 @@ def object_type
       #
       # @api public
       def run
-        [target_object_path, target_spec_path].compact.each do |target_file|
+        [target_object_path, target_addon_path, target_spec_path].compact.each do |target_file|
           next unless File.exist?(target_file)
 
           raise PDK::CLI::ExitWithError, _("Unable to generate %{object_type}; '%{file}' already exists.") % {
@@ -98,6 +106,7 @@ def run
           data = template_data.merge(configs: config_hash)
 
           render_file(target_object_path, template_path[:object], data)
+          render_file(target_addon_path, template_path[:addon], data) if template_path[:addon]
           render_file(target_spec_path, template_path[:spec], data) if template_path[:spec]
         end
       end

lib/pdk/module/templatedir.rb

@@ -153,10 +153,12 @@ def render
       # @api public
       def object_template_for(object_type)
         object_path = File.join(@object_dir, "#{object_type}.erb")
+        addon_path = File.join(@object_dir, "#{object_type}_addon.erb")
         spec_path = File.join(@object_dir, "#{object_type}_spec.erb")
 
         if File.file?(object_path) && File.readable?(object_path)
           result = { object: object_path }
+          result[:addon] = addon_path if File.file?(addon_path) && File.readable?(addon_path)
           result[:spec] = spec_path if File.file?(spec_path) && File.readable?(spec_path)
           result
         else

spec/acceptance/new_provider_spec.rb

@@ -0,0 +1,78 @@
+require 'spec_helper_acceptance'
+
+describe 'pdk new provider', module_command: true do
+  shared_examples 'it creates a provider' do |name|
+    describe command("pdk new provider #{name}") do
+      its(:stderr) { is_expected.to match(%r{creating .* from template}i) }
+      its(:stderr) { is_expected.not_to match(%r{WARN|ERR}) }
+      its(:stdout) { is_expected.to match(%r{\A\Z}) }
+      its(:exit_status) { is_expected.to eq(0) }
+    end
+
+    describe file('lib/puppet/type') do
+      it { is_expected.to be_directory }
+    end
+
+    describe file("lib/puppet/provider/#{name}") do
+      it { is_expected.to be_directory }
+    end
+
+    describe file("spec/unit/puppet/provider/#{name}") do
+      it { is_expected.to be_directory }
+    end
+
+    context 'with the experimental `puppet-resource_api` in the Gemfile' do
+      describe command('echo "gem \'puppet-resource_api\', git: \'https://github.com/puppetlabs/puppet-resource_api.git\'" >> Gemfile') do
+        its(:exit_status) { is_expected.to eq(0) }
+      end
+
+      describe command('echo "RSpec.configure { |c| c.mock_with :rspec }" >> spec/spec_helper.rb') do
+        its(:exit_status) { is_expected.to eq(0) }
+      end
+
+      describe command('rm -f Gemfile.lock') do
+        its(:exit_status) { is_expected.to eq(0) }
+      end
+
+      context 'when validating the generated code' do
+        describe command('pdk validate ruby') do
+          its(:stdout) { is_expected.to be_empty }
+          its(:stderr) { is_expected.to be_empty }
+          its(:exit_status) { is_expected.to eq(0) }
+        end
+      end
+
+      context 'when running the generated spec tests' do
+        describe command('pdk test unit') do
+          its(:stderr) { is_expected.to match(%r{0 failures}) }
+          its(:stderr) { is_expected.not_to match(%r{no examples found}i) }
+          its(:exit_status) { is_expected.to eq(0) }
+        end
+      end
+    end
+  end
+
+  context 'in a fresh module' do
+    include_context 'in a new module', 'new_provider'
+
+    context 'when creating a provider' do
+      it_behaves_like 'it creates a provider', 'test_provider'
+
+      describe file('lib/puppet/type/test_provider.rb') do
+        it { is_expected.to be_file }
+        its(:content) { is_expected.to match(%r{Puppet::ResourceApi.register_type}) }
+        its(:content) { is_expected.to match(%r{name: 'test_provider'}) }
+      end
+
+      describe file('lib/puppet/provider/test_provider/test_provider.rb') do
+        it { is_expected.to be_file }
+        its(:content) { is_expected.to match(%r{class Puppet::Provider::TestProvider::TestProvider}) }
+      end
+
+      describe file('spec/unit/puppet/provider/test_provider/test_provider_spec.rb') do
+        it { is_expected.to be_file }
+        its(:content) { is_expected.to match(%r{RSpec.describe Puppet::Provider::TestProvider::TestProvider do}) }
+      end
+    end
+  end
+end