Error out if LXC is not installed

This is enough to close #11

CHANGELOG.md

@@ -15,7 +15,7 @@ FEATURES:
 
 IMPROVEMENTS:
 
-  - Error out if `redir` is not installed but port forwarding was configured [#112](https://github.com/fgrehm/vagrant-lxc/issues/112)
+  - Error out if dependencies are not installed [#11](https://github.com/fgrehm/vagrant-lxc/issues/11) / [#112](https://github.com/fgrehm/vagrant-lxc/issues/112)
   - Support for specifying host interface/ip for binding `redir` [#76](https://github.com/fgrehm/vagrant-lxc/issues/76)
   - Add Vagrantfile VM name to the container name [#115](https://github.com/fgrehm/vagrant-lxc/issues/115)
   - Properly handle forwarded port collisions [#5](https://github.com/fgrehm/vagrant-lxc/issues/5)

README.md

@@ -139,14 +139,6 @@ for a list of [pre built](https://github.com/fgrehm/vagrant-lxc/wiki/Base-boxes#
 base boxes and information on [how to build your own](https://github.com/fgrehm/vagrant-lxc/wiki/Base-boxes#building-your-own).
 
 
-## Current limitations
-
-* [Does not tell you if dependencies are not met](https://github.com/fgrehm/vagrant-lxc/issues/11)
-  (will probably just throw up some random error)
-* + bunch of other [core features](https://github.com/fgrehm/vagrant-lxc/issues?labels=core&milestone=&page=1&state=open)
-  and some known [bugs](https://github.com/fgrehm/vagrant-lxc/issues?labels=bug&page=1&state=open)
-
-
 ## More information
 
 Please refer the [wiki](https://github.com/fgrehm/vagrant-lxc/wiki) for more

lib/vagrant-lxc/action.rb

@@ -25,7 +25,6 @@ module Vagrant
       # machine back up with the new configuration.
       def self.action_reload
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::Call, Created do |env1, b2|
             if !env1[:result]
               b2.use Message, :not_created
@@ -44,7 +43,6 @@ module Vagrant
       # a bootup (i.e. not saved).
       def self.action_boot
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use ClearForwardedPorts
           b.use Vagrant::Action::Builtin::Provision
           b.use Vagrant::Action::Builtin::EnvSet, :port_collision_repair => true
           b.use Vagrant::Action::Builtin::HandleForwardedPortCollisions
@@ -58,7 +56,6 @@ module Vagrant
       # This action just runs the provisioners on the machine.
       def self.action_provision
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::ConfigValidate
           b.use Vagrant::Action::Builtin::Call, Created do |env1, b2|
             if !env1[:result]
@@ -82,7 +79,6 @@ module Vagrant
       # A precondition of this action is that the container exists.
       def self.action_start
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::ConfigValidate
           b.use Vagrant::Action::Builtin::Call, IsRunning do |env, b2|
             # If the VM is running, then our work here is done, exit
@@ -97,7 +93,6 @@ module Vagrant
       # container, configuring metadata, and booting.
       def self.action_up
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::ConfigValidate
           b.use Vagrant::Action::Builtin::Call, Created do |env, b2|
             # If the VM is NOT created yet, then do the setup steps
@@ -115,7 +110,6 @@ module Vagrant
       # the virtual machine, gracefully or by force.
       def self.action_halt
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::Call, Created do |env, b2|
             if env[:result]
               # TODO: Remove this on / after 0.4
@@ -138,7 +132,6 @@ module Vagrant
       # freeing the resources of the underlying virtual machine.
       def self.action_destroy
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::Call, Created do |env1, b2|
             if !env1[:result]
               b2.use Message, :not_created
@@ -162,7 +155,6 @@ module Vagrant
       # This action packages the virtual machine into a single box file.
       def self.action_package
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use Vagrant::Action::Builtin::Call, Created do |env1, b2|
             if !env1[:result]
               b2.use Message, :not_created
@@ -180,7 +172,6 @@ module Vagrant
       # This is the action that will exec into an SSH shell.
       def self.action_ssh
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use CheckCreated
           b.use CheckRunning
           b.use Vagrant::Action::Builtin::SSHExec
@@ -190,7 +181,6 @@ module Vagrant
       # This is the action that will run a single SSH command.
       def self.action_ssh_run
         Vagrant::Action::Builder.new.tap do |b|
-          # b.use CheckDependencies
           b.use CheckCreated
           b.use CheckRunning
           b.use Vagrant::Action::Builtin::SSHRun

lib/vagrant-lxc/errors.rb

@@ -7,6 +7,10 @@ module Vagrant
         error_key(:lxc_execute_error)
       end
 
+      class LxcNotInstalled < Vagrant::Errors::VagrantError
+        error_key(:lxc_not_installed)
+      end
+
       # Box related errors
       class TemplateFileMissing < Vagrant::Errors::VagrantError
         error_key(:lxc_template_file_missing)

lib/vagrant-lxc/provider.rb

@@ -14,6 +14,7 @@ module Vagrant
         @logger    = Log4r::Logger.new("vagrant::provider::lxc")
         @machine   = machine
 
+        ensure_lxc_installed!
         machine_id_changed
       end
 
@@ -25,6 +26,12 @@ module Vagrant
         end
       end
 
+      def ensure_lxc_installed!
+        unless system("which lxc-version > /dev/null")
+          raise Errors::LxcNotInstalled
+        end
+      end
+
       # If the machine ID changed, then we need to rebuild our underlying
       # container.
       def machine_id_changed

locales/en.yml

@@ -45,5 +45,8 @@ en:
         The template file used for creating the container was not found for %{name}
         box.
 
+      lxc_not_installed: |-
+        The `lxc` package does not seem to be installed or is not accessible on the PATH.
+
       lxc_redir_not_installed: |-
         `redir` is not installed or is not accessible on the PATH.