From d0f728b3539fbcdb10237da6b92f76da18066cb2 Mon Sep 17 00:00:00 2001
From: John Bender <john.m.bender@gmail.com>
Date: Tue, 2 Feb 2010 00:48:38 -0800
Subject: [PATCH] suspend and resume, test for both and failures, small
 refactor of the Hobo::VM#start and the use of Ping.pingecho in SSH.up?

---
 bin/hobo-resume      | 26 ++++++++++++++++++++
 bin/hobo-suspend     | 26 ++++++++++++++++++++
 lib/hobo.rb          |  2 ++
 lib/hobo/env.rb      | 13 ++--------
 lib/hobo/error.rb    | 14 +++++++++++
 lib/hobo/ssh.rb      |  6 ++++-
 lib/hobo/vm.rb       | 53 ++++++++++++++++++++++++++++------------
 test/hobo/vm_test.rb | 57 ++++++++++++++++++++++++++++++++++++++------
 8 files changed, 163 insertions(+), 34 deletions(-)
 create mode 100755 bin/hobo-resume
 create mode 100755 bin/hobo-suspend
 create mode 100644 lib/hobo/error.rb

diff --git a/bin/hobo-resume b/bin/hobo-resume
new file mode 100755
index 000000000..15c8369a2
--- /dev/null
+++ b/bin/hobo-resume
@@ -0,0 +1,26 @@
+#!/usr/bin/env ruby
+begin
+  require File.expand_path(File.join(File.dirname(__FILE__), "../vendor/gems/ruby/1.8/environment"))
+rescue LoadError
+end
+
+require 'git-style-binary/command'
+
+# Get hobo
+hobodir = File.join(File.dirname(__FILE__), '..', 'lib')
+$:.unshift(hobodir) unless $:.include?(hobodir)
+require 'hobo'
+
+GitStyleBinary.command do
+  short_desc "resumes the hobo environment"
+  banner <<-EOS
+Usage: #{command.full_name} #{all_options_string}
+
+Resumes the hobo environment.
+
+EOS
+
+  run do |command|
+    Hobo::VM.resume
+  end
+end
diff --git a/bin/hobo-suspend b/bin/hobo-suspend
new file mode 100755
index 000000000..ff5594809
--- /dev/null
+++ b/bin/hobo-suspend
@@ -0,0 +1,26 @@
+#!/usr/bin/env ruby
+begin
+  require File.expand_path(File.join(File.dirname(__FILE__), "../vendor/gems/ruby/1.8/environment"))
+rescue LoadError
+end
+
+require 'git-style-binary/command'
+
+# Get hobo
+hobodir = File.join(File.dirname(__FILE__), '..', 'lib')
+$:.unshift(hobodir) unless $:.include?(hobodir)
+require 'hobo'
+
+GitStyleBinary.command do
+  short_desc "suspends the hobo environment"
+  banner <<-EOS
+Usage: #{command.full_name} #{all_options_string}
+
+Suspends the hobo environment.
+
+EOS
+
+  run do |command|
+    Hobo::VM.suspend
+  end
+end
diff --git a/lib/hobo.rb b/lib/hobo.rb
index 8e3768f41..7a34b4ca3 100644
--- a/lib/hobo.rb
+++ b/lib/hobo.rb
@@ -7,6 +7,8 @@ require 'pathname'
 require 'logger'
 require 'virtualbox'
 require 'net/ssh'
+require 'ping'
+require 'hobo/error'
 require 'hobo/config'
 require 'hobo/env'
 require 'hobo/ssh'
diff --git a/lib/hobo/env.rb b/lib/hobo/env.rb
index ec3d325b5..f0b553fe2 100644
--- a/lib/hobo/env.rb
+++ b/lib/hobo/env.rb
@@ -7,6 +7,8 @@ module Hobo
     # Initialize class variables used
     @@persisted_vm = nil
     @@root_path = nil
+    
+    extend Hobo::Error
 
     class << self
       def persisted_vm; @@persisted_vm; end
@@ -79,17 +81,6 @@ error
           return
         end
       end
-
-      def error_and_exit(error)
-        puts <<-error
-=====================================================================
-Hobo experienced an error!
-
-#{error.chomp}
-=====================================================================
-error
-        exit
-      end
     end
   end
 end
diff --git a/lib/hobo/error.rb b/lib/hobo/error.rb
new file mode 100644
index 000000000..d9f5145c7
--- /dev/null
+++ b/lib/hobo/error.rb
@@ -0,0 +1,14 @@
+module Hobo
+  module Error
+      def error_and_exit(error)
+        puts <<-error
+=====================================================================
+Hobo experienced an error!
+
+#{error.chomp}
+=====================================================================
+error
+        exit
+      end
+  end
+end
diff --git a/lib/hobo/ssh.rb b/lib/hobo/ssh.rb
index c3019ae7c..7d483daa4 100644
--- a/lib/hobo/ssh.rb
+++ b/lib/hobo/ssh.rb
@@ -2,7 +2,7 @@ module Hobo
   class SSH
     SCRIPT = File.join(File.dirname(__FILE__), '..', '..', 'script', 'hobo-ssh-expect.sh')
 
-    class <<self
+    class << self
       def connect(opts={})
         options = {}
         [:port, :host, :pass, :uname].each do |param|
@@ -17,6 +17,10 @@ module Hobo
           yield ssh
         end
       end
+
+      def up?
+        Ping.pingecho "localhost", 1, Hobo.config[:ssh][:port]
+      end
     end
   end
 end
diff --git a/lib/hobo/vm.rb b/lib/hobo/vm.rb
index 0cd8ec1a9..ba2c77f53 100644
--- a/lib/hobo/vm.rb
+++ b/lib/hobo/vm.rb
@@ -2,7 +2,9 @@ module Hobo
   class VM
     attr_reader :vm
 
-    class <<self
+    extend Hobo::Error
+
+    class << self
       # Bring up the virtual machine. Imports the base image and
       # provisions it.
       def up
@@ -21,6 +23,27 @@ module Hobo
         SSH.connect
       end
 
+      
+      # Save the state of the current hobo environment to disk
+      def suspend
+        Env.require_persisted_vm
+        error_and_exit(<<-error) if Env.persisted_vm.saved?
+The hobo virtual environment you are trying to reume is already in a
+suspended state.
+error
+        Env.persisted_vm.save_state(true)
+      end
+
+      # Resume the current hobo environment from disk
+      def resume
+        Env.require_persisted_vm
+        error_and_exit(<<-error) unless Env.persisted_vm.saved?
+The hobo virtual environment you are trying to resume is not in a
+suspended state.
+error
+        Env.persisted_vm.start
+      end
+
       # Finds a virtual machine by a given UUID and either returns
       # a Hobo::VM object or returns nil.
       def find(uuid)
@@ -94,23 +117,23 @@ module Hobo
 
       # Now we have to wait for the boot to be successful
       HOBO_LOGGER.info "Waiting for VM to boot..."
-      counter = 1
-      begin
+      
+      Hobo.config[:ssh][:max_tries].to_i.times do |i|
         sleep 5 unless ENV['HOBO_ENV'] == 'test'
-        HOBO_LOGGER.info "Trying to connect (attempt ##{counter} of #{Hobo.config[:ssh][:max_tries]})..."
-        SSH.execute { |ssh| }
-      rescue Errno::ECONNREFUSED
-        if counter >= Hobo.config[:ssh][:max_tries].to_i
-          HOBO_LOGGER.info "Failed to connect to VM! Failed to boot?"
-          return false
+        HOBO_LOGGER.info "Trying to connect (attempt ##{i+1} of #{Hobo.config[:ssh][:max_tries]})..."
+        
+        if Hobo::SSH.up?
+          HOBO_LOGGER.info "VM booted and ready for use!"
+          return true
         end
-
-        counter += 1
-        retry
       end
 
-      HOBO_LOGGER.info "VM booted and ready for use!"
-      true
+      HOBO_LOGGER.info "Failed to connect to VM! Failed to boot?"
+      false
     end
+
+    def saved?; @vm.saved? end
+    
+    def save_state(errs); @vm.save_state(errs) end
   end
-end
\ No newline at end of file
+end
diff --git a/test/hobo/vm_test.rb b/test/hobo/vm_test.rb
index 90c29155c..bbcfea8a3 100644
--- a/test/hobo/vm_test.rb
+++ b/test/hobo/vm_test.rb
@@ -112,15 +112,15 @@ class VMTest < Test::Unit::TestCase
         @vm.start
       end
 
-      should "repeatedly SSH while waiting for the VM to start" do
-        ssh_seq = sequence("ssh_seq")
-        Net::SSH.expects(:start).once.raises(Errno::ECONNREFUSED).in_sequence(ssh_seq)
-        Net::SSH.expects(:start).once.in_sequence(ssh_seq)
-        @vm.start
+      should "repeatedly ping the SSH port and return false with no response" do
+        seq = sequence('pings')
+        Ping.expects(:pingecho).times(Hobo.config[:ssh][:max_tries].to_i - 1).returns(false).in_sequence(seq)
+        Ping.expects(:pingecho).once.returns(true).in_sequence(seq)
+        assert @vm.start
       end
 
-      should "try the max number of times then just return" do
-        Net::SSH.expects(:start).times(Hobo.config[:ssh][:max_tries].to_i).raises(Errno::ECONNREFUSED)
+      should "ping the max number of times then just return" do
+        Ping.expects(:pingecho).times(Hobo.config[:ssh][:max_tries].to_i).returns(false)
         assert !@vm.start
       end
     end
@@ -182,5 +182,48 @@ class VMTest < Test::Unit::TestCase
         @vm.setup_shared_folder
       end
     end
+
+    context "suspending a vm" do
+      should "put the vm in a suspended state" do 
+        saved_state_expectations(false)
+        Hobo::VM.suspend
+      end
+
+      should "results in an error and exit if the vm is already in a saved state" do
+        saved_state_expectations(true)
+        Hobo::VM.expects(:error_and_exit)
+        Hobo::VM.suspend
+      end
+
+      def saved_state_expectations(saved)
+        @persisted_vm.expects(:saved?).returns(saved)
+
+        # In this case the exit, is ignored so the expectation of save_state on the persisted
+        # vm must be set
+        @persisted_vm.expects(:save_state).with(true)
+      end
+    end
+
+    context "resuming a vm" do
+      should "start a vm in a suspended state" do 
+        start_state_expectaions(true)
+        Hobo::VM.resume
+      end
+
+      should "results in an error and exit if the vm is not in a saved state" do
+        start_state_expectaions(false)
+        
+        # In this case the exit, is ignored so the expectation of start on the persisted
+        # vm must be set
+        # TODO research the matter of mocking exit
+        Hobo::VM.expects(:error_and_exit)
+        Hobo::VM.resume
+      end
+
+      def start_state_expectaions(saved)
+        @persisted_vm.expects(:saved?).returns(saved)
+        Hobo::Env.persisted_vm.expects(:start).once.returns(true)
+      end
+    end
   end
 end