Merge pull request #4 from chef/docker

Start Docker + SSH backends

lib/vulcano/backend.rb

@@ -37,6 +37,8 @@ module Vulcano
   end
 end
 
+require 'vulcano/backend/docker'
 require 'vulcano/backend/local'
 require 'vulcano/backend/mock'
 require 'vulcano/backend/specinfra'
+require 'vulcano/backend/ssh'

lib/vulcano/backend/docker.rb

@@ -0,0 +1,33 @@
+# encoding: utf-8
+require 'docker'
+
+module Vulcano::Backends
+  class Docker < Vulcano.backend(1)
+    name 'docker'
+
+    def initialize(conf)
+      @conf = conf
+      @files = {}
+      id = @conf['host'] ||
+        fail("You must specify a docker container ID.")
+      @container = ::Docker::Container.get(id) ||
+        fail("Can't find Docker container #{id}")
+    end
+
+    def file(path)
+      @files[path] ||= LinuxFile.new(self, path)
+    end
+
+    def run_command(cmd)
+      stdout, stderr, exit_status = @container.exec([
+        '/bin/sh', '-c', cmd
+      ])
+      CommandResult.new(stdout.join, stderr.join, exit_status)
+    rescue ::Docker::Error::DockerError => err
+      raise
+    rescue => err
+      # @TODO: differentiate any other error
+      raise
+    end
+  end
+end

lib/vulcano/backend/ssh.rb

@@ -0,0 +1,86 @@
+# encoding: utf-8
+
+module Vulcano::Backends
+  class SSH < Vulcano.backend(1)
+    name 'ssh'
+
+    def initialize(conf)
+      @conf = conf
+      @files = {}
+      @conf['host'] ||
+        fail("You must specify a SSH host.")
+      @ssh = start_ssh
+    end
+
+    def file(path)
+      @files[path] ||= LinuxFile.new(self, path)
+    end
+
+    def run_command(cmd)
+      stdout = stderr = ''
+      exit_status = nil
+
+      @ssh.open_channel do |channel|
+        channel.exec(cmd) do |ch, success|
+          unless success
+            fail "Couldn't execute command on SSH."
+          end
+
+          channel.on_data do |ch,data|
+            stdout += data
+          end
+
+          channel.on_extended_data do |ch,type,data|
+            stderr += data
+          end
+
+          channel.on_request("exit-status") do |ch,data|
+            exit_status = data.read_long
+          end
+
+          channel.on_request("exit-signal") do |ch, data|
+            exit_status = data.read_long
+          end
+        end
+      end
+      @ssh.loop
+
+      CommandResult.new(stdout, stderr, exit_status)
+    end
+
+    private
+
+    def start_ssh
+      host = @conf['host']
+      ssh_config = Net::SSH.configuration_for(host)
+
+      user = @conf['user'] || ssh_config[:user]
+      keys = [ @conf['key_file'], ssh_config[:keys] ].flatten.compact
+      options = {
+        port: @conf['port'] || ssh_config[:port] || 22,
+        auth_methods: ['none'],
+        user_known_hosts_file: '/dev/null',
+        global_known_hosts_file: '/dev/null',
+        number_of_password_prompts: 0,
+        password: @conf['password'] || ssh_config[:password],
+        keys: keys,
+      }
+
+      unless options[:keys].empty?
+        options[:auth_methods].push('publickey')
+        options[:keys_only] = true if options[:password].nil?
+      end
+
+      unless options[:password].nil?
+        options[:auth_methods].push('password')
+      end
+
+      if options[:keys].empty? and options[:password].nil?
+        fail('You must configure at least one authentication method for SSH:' +
+          ' Password or key.')
+      end
+
+      Net::SSH.start( host, user, options )
+    end
+  end
+end

lib/vulcano/plugins/backend.rb

@@ -6,6 +6,7 @@ module Vulcano::Plugins
   class Backend
     autoload :FileCommon, 'vulcano/plugins/backend_file_common'
     autoload :LinuxFile,  'vulcano/plugins/backend_linux_file'
+    CommandResult = Struct.new(:stdout, :stderr, :exit_status)
 
     def self.name(name)
       Vulcano::Plugins::Backend.__register(name, self)