feature: add interactive shell

lib/vulcano.rb

@@ -16,4 +16,5 @@ require 'vulcano/resource'
 require 'vulcano/rspec_json_formatter'
 require 'vulcano/rule'
 require 'vulcano/runner'
+require 'vulcano/shell'
 require 'matchers/matchers'

lib/vulcano/shell.rb

@@ -0,0 +1,58 @@
+# encoding: utf-8
+# author: Dominik Richter
+# author: Christoph Hartmann
+
+module Vulcano::Shell
+  def self.start(runner)
+    # load and configure pry
+    require 'pry'
+    configure_pry
+
+    runner.add_content('binding.pry', __FILE__, __LINE__)
+    runner.run
+  end
+
+  def self.configure_pry
+    # Remove all hooks and checks
+    Pry.hooks.clear_all
+
+    # Add the help command
+    Pry::Commands.block_command 'usage', 'Show examples' do
+      Vulcano::Shell.usage
+    end
+
+    # Add a help menu as the default intro
+    Pry.hooks.add_hook(:before_session, :intro) do
+      intro
+    end
+  end
+
+  def self.mark(x)
+    "\033[1m#{x}\033[0m"
+  end
+
+  def self.intro
+    puts 'Welcome to the interactive Vulcano Shell'
+    puts "To find out how to use it, type: #{mark 'usage'}"
+    puts
+  end
+
+  def self.usage
+    puts <<EOF
+
+Welcome to the interactive Vulcano Shell.
+
+You can use resources in this environment to test the target machine.
+For example:
+
+    command('uname -a').stdout
+    file('/proc/cpuinfo').content
+
+You are currently running on:
+
+    OS family:  #{mark os[:family] || 'unknown'}
+    OS release: #{mark os[:release] || 'unknown'}
+
+EOF
+  end
+end

vulcano.gemspec

@@ -29,4 +29,5 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'mixlib-shellout', '~> 2'
   spec.add_dependency 'specinfra', '~> 2.40'
   spec.add_dependency 'docker-api', '~> 1.22'
+  spec.add_dependency 'pry', '~> 0.10'
 end