Implement command to update /etc/hosts files.

This commit disables automatic updates by default instead preferring
the user to execute the hostmanager sub-command. The user can enable
auto updates via configuration.

README.md

@@ -11,19 +11,31 @@ The current implementation is a proof-of-concept supporting the larger
 objective of using Vagrant as a cloud management interface for development
 and production environments.
 
-The plugin has been tested with Vagrant 1.1.4.
+The plugin has been tested with Vagrant 1.1.5.
 
 Installation
 ------------
 Install the plugin following the typical Vagrant 1.1 procedure:
 
-    vagrant plugin install vagrant-hostmanager
+    $ vagrant plugin install vagrant-hostmanager
 
 Usage
 -----
-The plugin hooks into the `vagrant up` and `vagrant destroy` commands
+To update the `/etc/hosts` file on each active machine, run the following
-automatically updating the `/etc/hosts` file on each active machine that
+command:
-is using the same provider.
+
+    $ vagrant hostmanager
+
+The plugin may hook into the `vagrant up` and `vagrant destroy` commands
+automatically to update the `/etc/hosts` file on each active machine that
+is using the same provider. To enable this, add the following configuration
+to your Vagrant file:
+
+```ruby
+Vagrant.configure('2') do |config|
+  config.hostmanager.auto_update = true
+end
+```
 
 A machine's IP address is defined by either the static IP for a private
 network configuration or by the SSH host configuration.

lib/vagrant-hostmanager/action/update_hosts_file.rb

@@ -1,66 +1,31 @@
+require 'vagrant-hostmanager/hosts_file'
+
 module VagrantPlugins
   module HostManager
     module Action
       class UpdateHostsFile
+        include HostsFile
+
         def initialize(app, env)
-          @app, @env = app, env
+          @app = app
+          @machine = env[:machine]
           @translator = Helpers::Translator.new('action.update_hosts_file')
           @logger =
             Log4r::Logger.new('vagrant_hostmanager::action::update')
         end
 
         def call(env)
-          global_env = env[:machine].env
+          # check config to see if the hosts file should updated automatically
-          current_provider = env[:machine].provider_name
+          if @machine.config.hostmanager.auto_update
+            # generate temporary hosts file
+            machines = generate(@machine.env, @machine.provider_name)
 
-          # build a list of host entries based on active machines that
+            # update /etc/hosts file on each active machine
-          # are using the same provider as the current one
+            machines.each { |machine| update(machine) }
-          matching_machines = []
-          entries = {}
-          entries['127.0.0.1'] = 'localhost'
-          global_env.active_machines.each do |name, provider|
-            if provider == current_provider
-              machine = global_env.machine(name, provider)
-              host = machine.config.vm.hostname || name
-              entries[get_ip_address(machine)] = host
-              matching_machines << machine
-            end
-          end
-
-          # generate hosts file
-          path = env[:tmp_path].join('hosts')
-          File.open(path, 'w') do |file|
-            entries.each_pair do |ip, host|
-              @logger.info "Adding /etc/hosts entry: #{ip} #{host}"
-              file << "#{ip}\t#{host}\n"
-            end
-          end
-
-          # copy the hosts file to each matching machine
-          # TODO append hostname to loopback address
-          matching_machines.each do |machine|
-            if machine.communicate.ready?
-              env[:ui].info @translator.t('update', { :name => machine.name })
-              machine.communicate.upload(path, '/tmp/hosts')
-              machine.communicate.sudo("mv /tmp/hosts /etc/hosts")
-            end
           end
 
           @app.call(env)
         end
-
-        protected
-
-        def get_ip_address(machine)
-          ip = nil
-          machine.config.vm.networks.each do |network|
-            key, options = network[0], network[1]
-            ip = options[:ip] if key == :private_network
-            next if ip
-          end
-
-          ip || machine.ssh_info[:host]
-        end
       end
     end
   end

lib/vagrant-hostmanager/command.rb

@@ -0,0 +1,29 @@
+module VagrantPlugins
+  module HostManager
+    class Command < Vagrant.plugin('2', :command)
+      include HostsFile
+
+      def execute
+        options = {}
+        opts = OptionParser.new do |o|
+          o.banner = 'Usage: vagrant hostmanager [vm-name]'
+          o.separator ''
+
+          o.on('--provider provider', String,
+            'Update machines with the specific provider.') do |provider|
+            options[:provider] = provider
+          end
+        end
+
+        argv = parse_options(opts)
+        options[:provider] ||= @env.default_provider
+
+        generate(@env, options[:provider])
+
+        with_target_vms(argv[1..-1], :provider => options[:provider]) do |machine|
+          update(machine)
+        end
+      end
+    end
+  end
+end

lib/vagrant-hostmanager/config.rb

@@ -0,0 +1,20 @@
+module VagrantPlugins
+  module HostManager
+    class Config < Vagrant.plugin('2', :config)
+      attr_accessor :auto_update
+
+      def initialize
+        @auto_update = false
+      end
+
+      def validate(machine)
+        errors = []
+        if !(!!@auto_update == @auto_update)
+          errors << 'auto_update must be a boolean' 
+        end
+
+        { 'hostmanager' => errors }
+      end
+    end
+  end
+end

lib/vagrant-hostmanager/hosts_file.rb

@@ -0,0 +1,57 @@
+module VagrantPlugins
+  module HostManager
+    module HostsFile
+      # Generate a hosts file containing the the active machines
+      # in the Vagrant environment backed by the specified provider.
+      # The file is written to the Vagrant temporary path.
+      def generate(env, provider)
+        machines = []
+
+        # define a lambda for looking up a machine's ip address
+        get_ip_address = lambda do |machine|
+          ip = nil
+          machine.config.vm.networks.each do |network|
+            key, options = network[0], network[1]
+            ip = options[:ip] if key == :private_network
+            next if ip
+          end
+          ip || machine.ssh_info[:host]
+        end
+
+        # create the temporary hosts file
+        path = env.tmp_path.join('hosts')
+        File.open(path, 'w') do |file|
+          file << "127.0.0.1\tlocalhost\n"
+
+          # add a hosts entry for each active machine matching the provider
+          env.active_machines.each do |name, p|
+            if provider == p
+              machines << machine = env.machine(name, provider)
+              host = machine.config.vm.hostname || name
+              ip = get_ip_address.call(machine)
+              @logger.info "Adding /etc/hosts entry: #{ip} #{host}"
+              file << "#{ip}\t#{host}\n"
+            end
+          end
+        end
+
+        machines
+      end
+
+      # Copy the temporary hosts file to the specified machine overwritting
+      # the existing /etc/hosts file.
+      def update(machine)
+        path = machine.env.tmp_path.join('hosts')
+        if machine.communicate.ready?
+          machine.env.ui.info translator.t('update', { :name => machine.name })
+          machine.communicate.upload(path, '/tmp/hosts')
+          machine.communicate.sudo("mv /tmp/hosts /etc/hosts")
+        end
+      end
+
+      def translator
+        Helpers::Translator.new('hosts_file')
+      end
+    end
+  end
+end

lib/vagrant-hostmanager/plugin.rb

@@ -10,16 +10,26 @@ module VagrantPlugins
         created for each active machine using the hostname attribute.
       DESC
 
-      action_hook(:hostmanager_up, :machine_action_up) do |hook|
+      def self.update(hook)
         setup_i18n
         setup_logging
         hook.append(Action::UpdateHostsFile)
       end
 
-      action_hook(:hostmanger_destroy, :machine_action_destroy) do |hook|
+      config(:hostmanager) do
+        require_relative 'config'
+        Config
+      end
+
+      action_hook(:hostmanager_up, :machine_action_up, &method(:update))
+      action_hook(:hostmanger_destroy, :machine_action_destroy, &method(:update))
+
+      # TODO remove duplication of i18n and logging setup
+      command(:hostmanager) do 
         setup_i18n
         setup_logging
-        hook.append(Action::UpdateHostsFile)
+        require_relative 'command'
+        Command
       end
 
       def self.setup_i18n

lib/vagrant-hostmanager/version.rb

@@ -1,5 +1,5 @@
 module VagrantPlugins
   module HostManager
-    VERSION = '0.0.3'
+    VERSION = '0.0.4'
   end
 end

locales/en.yml

@@ -1,5 +1,4 @@
 en:
   vagrant_hostmanager:
-    action:
+    hosts_file:
-      update_hosts_file:
+      update: "[%{name}] Updating /etc/hosts file"
-        update: "Updating /etc/hosts file on %{name}"

test/test.sh

@@ -6,12 +6,13 @@ vagrant ssh server1 -c 'cat /etc/hosts'
 echo "[server2] /etc/hosts file:"
 vagrant ssh server2 -c 'cat /etc/hosts'
 
-vagrant halt
+vagrant hostmanager
-vagrant up
 
-vagrant destroy server1 -f
+echo "[server1] /etc/hosts file:"
+vagrant ssh server1 -c 'cat /etc/hosts'
 echo "[server2] /etc/hosts file:"
 vagrant ssh server2 -c 'cat /etc/hosts'
-vagrant destroy server2 -f
+
+vagrant destroy -f
 
 cd ..