Support hooking around provisioners runs

lib/vagrant/action.rb

@@ -21,6 +21,7 @@ module Builtin
       autoload :NFS, "vagrant/action/builtin/nfs"
       autoload :Provision, "vagrant/action/builtin/provision"
       autoload :ProvisionerCleanup, "vagrant/action/builtin/provisioner_cleanup"
+      autoload :ProvisionerRun,     "vagrant/action/builtin/provisioner_run"
       autoload :SetHostname, "vagrant/action/builtin/set_hostname"
       autoload :SSHExec, "vagrant/action/builtin/ssh_exec"
       autoload :SSHRun,  "vagrant/action/builtin/ssh_run"

lib/vagrant/action/builtin/provision.rb

@@ -71,7 +71,21 @@ def run_provisioner(env, name, p)
           env[:ui].info(I18n.t("vagrant.actions.vm.provision.beginning",
                                :provisioner => name))
 
-          p.provision
+          callable = Builder.new.tap { |b| b.use ProvisionerRun, p }
+          action_runner.run(callable,
+            :action_name   => :provisioner_run,
+            :provider_name => name
+          )
+        end
+
+        def action_runner
+          @action_runner ||= Action::Runner.new do
+            {
+              :env     => @env[:env],
+              :machine => @env[:machine],
+              :ui      => @env[:ui]
+            }
+          end
         end
       end
     end

lib/vagrant/action/builtin/provisioner_run.rb

@@ -0,0 +1,21 @@
+require "log4r"
+
+module Vagrant
+  module Action
+    module Builtin
+      # This action is basically a wrapper on top of provisioner runs that
+      # enable plugins to hook around the provisioning itself
+      class ProvisionerRun
+        def initialize(app, env, provisioner)
+          @app         = app
+          @provisioner = provisioner
+        end
+
+        def call(env)
+          @app.call(env)
+          @provisioner.provision
+        end
+      end
+    end
+  end
+end