vmpooler/spec/unit/providers/vsphere_spec.rb

require 'spec_helper'
require 'mock_redis'
require 'vmpooler/providers/vsphere'

RSpec::Matchers.define :relocation_spec_with_host do |value|
  match { |actual| actual[:spec].host == value }
end

RSpec::Matchers.define :create_virtual_disk_with_size do |value|
  match { |actual| actual[:spec].capacityKb == value * 1024 * 1024 }
end

RSpec::Matchers.define :create_vm_spec do |new_name,target_folder_name,datastore|
  match { |actual|
    # Should have the correct new name
    actual[:name] == new_name &&
    # Should be in the new folder
    actual[:folder].name == target_folder_name &&
    # Should be poweredOn after clone
    actual[:spec].powerOn == true &&
    # Should be on the correct datastore
    actual[:spec][:location].datastore.name == datastore &&
    # Should contain annotation data
    actual[:spec][:config].annotation != '' &&
    # Should contain VIC information
    actual[:spec][:config].extraConfig[0][:key] == 'guestinfo.hostname' &&
    actual[:spec][:config].extraConfig[0][:value] == new_name
  }
end

RSpec::Matchers.define :create_snapshot_spec do |new_snapshot_name|
  match { |actual|
    # Should have the correct new name
    actual[:name] == new_snapshot_name &&
    # Should snapshot the memory too
    actual[:memory] == true &&
    # Should quiesce the disk
    actual[:quiesce] == true
  }
end

describe 'Vmpooler::PoolManager::Provider::VSphere' do
  let(:logger) { MockLogger.new }
  let(:metrics) { Vmpooler::Metrics::DummyStatsd.new }
  let(:poolname) { 'pool1'}
  let(:provider_options) { { 'param' => 'value' } }
  let(:datacenter_name) { 'MockDC' }
  let(:config) { YAML.load(<<-EOT
---
:config:
  max_tries: 3
  retry_factor: 10
:providers:
  :vsphere:
    server: "vcenter.domain.local"
    username: "vcenter_user"
    password: "vcenter_password"
    insecure: true
    # Drop the connection pool timeout way down for spec tests so they fail fast
    connection_pool_timeout: 1
    datacenter: MockDC
    create_linked_clones: true
:pools:
  - name: '#{poolname}'
    alias: [ 'mockpool' ]
    template: 'Templates/pool1'
    folder: 'Pooler/pool1'
    datastore: 'datastore0'
    size: 5
    timeout: 10
    ready_ttl: 1440
    clone_target: 'cluster1'
EOT
    )
  }

  let(:connection_options) {{}}
  let(:connection) { mock_RbVmomi_VIM_Connection(connection_options) }
  let(:vmname) { 'vm1' }
  let(:redis_connection_pool) { Vmpooler::PoolManager::GenericConnectionPool.new(
    metrics: metrics,
    connpool_type: 'redis_connection_pool',
    connpool_provider: 'testprovider',
    size: 1,
    timeout: 5
  ) { MockRedis.new }
  }

  subject { Vmpooler::PoolManager::Provider::VSphere.new(config, logger, metrics, redis_connection_pool, 'vsphere', provider_options) }

  before(:each) do
    allow(subject).to receive(:vsphere_connection_ok?).and_return(true)
  end

  describe '#name' do
    it 'should be vsphere' do
      expect(subject.name).to eq('vsphere')
    end
  end

  describe '#folder_configured?' do
    let(:folder_title) { 'folder1' }
    let(:other_folder) { 'folder2' }
    let(:base_folder) { 'dc1/vm/base' }
    let(:configured_folders) { { folder_title => base_folder } }
    let(:whitelist) { nil }
    it 'should return true when configured_folders includes the folder_title' do
      expect(subject.folder_configured?(folder_title, base_folder, configured_folders, whitelist)).to be true
    end

    it 'should return false when title is not in configured_folders' do
      expect(subject.folder_configured?(other_folder, base_folder, configured_folders, whitelist)).to be false
    end

    context 'with another base folder' do
      let(:base_folder) { 'dc2/vm/base' }
      let(:configured_folders) { { folder_title => 'dc1/vm/base' } }
      it 'should return false' do
        expect(subject.folder_configured?(folder_title, base_folder, configured_folders, whitelist)).to be false
      end
    end

    context 'with a whitelist set' do
      let(:whitelist) { [ other_folder ] }
      it 'should return true' do
        expect(subject.folder_configured?(other_folder, base_folder, configured_folders, whitelist)).to be true
      end
    end

    context 'with string whitelist value' do
      let(:whitelist) { 'whitelist' }
      it 'should raise an error' do
        expect(whitelist).to receive(:include?).and_raise('mockerror')

        expect{ subject.folder_configured?(other_folder, base_folder, configured_folders, whitelist) }.to raise_error(RuntimeError, 'mockerror')
      end
    end
  end

  describe '#destroy_vm_and_log' do
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({
        :name => vmname,
        :powerstate => 'poweredOn',
      })
    }
    let(:pool) { 'pool1' }
    let(:power_off_task) { mock_RbVmomi_VIM_Task() }
    let(:destroy_task) { mock_RbVmomi_VIM_Task() }
    let(:data_ttl) { 1 }
    let(:finish) { '0.00' }
    let(:now) { Time.now }

    context 'when destroying a vm' do
      before(:each) do
        allow(power_off_task).to receive(:wait_for_completion)
        allow(destroy_task).to receive(:wait_for_completion)
        allow(vm_object).to receive(:PowerOffVM_Task).and_return(power_off_task)
        allow(vm_object).to receive(:Destroy_Task).and_return(destroy_task)
      end

      it 'should log a message that the vm is destroyed' do
        # Ensure Time returns a consistent value so finish is predictable
        # Otherwise finish occasionally increases to 0.01 and causes a failure
        allow(Time).to receive(:now).and_return(Time.now)
        expect(logger).to receive(:log).with('s', "[-] [#{pool}] '#{vmname}' destroyed in #{finish} seconds")

        subject.destroy_vm_and_log(vmname, vm_object, pool, data_ttl)
      end

      it 'should record metrics' do
        expect(metrics).to receive(:timing).with('connection_waited.redis_connection_pool.testprovider', 0)
        expect(metrics).to receive(:timing).with("destroy.#{pool}", finish)

        subject.destroy_vm_and_log(vmname, vm_object, pool, data_ttl)
      end

      it 'should power off and destroy the vm' do
        allow(destroy_task).to receive(:wait_for_completion)
        expect(vm_object).to receive(:PowerOffVM_Task).and_return(power_off_task)
        expect(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        subject.destroy_vm_and_log(vmname, vm_object, pool, data_ttl)
      end
    end

    context 'with a powered off vm' do
      before(:each) do
        vm_object.runtime.powerState = 'poweredOff'
      end

      it 'should destroy the vm without attempting to power it off' do
        allow(destroy_task).to receive(:wait_for_completion)
        expect(vm_object).to_not receive(:PowerOffVM_Task)
        expect(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        subject.destroy_vm_and_log(vmname, vm_object, pool, data_ttl)
      end
    end

    context 'with a folder object' do
      let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => vmname }) }

      it 'should log that a folder object was received' do
        expect(logger).to receive(:log).with('s', "[!] [#{pool}] '#{vmname}' is a folder, bailing on destroying")

        expect{ subject.destroy_vm_and_log(vmname, folder_object, pool, data_ttl) }.to raise_error(RuntimeError, 'Expected VM, but received a folder object')
      end

      it 'should raise an error' do
        expect{ subject.destroy_vm_and_log(vmname, folder_object, pool, data_ttl) }.to raise_error(RuntimeError, 'Expected VM, but received a folder object')
      end
    end

    context 'with an error that is not a RuntimeError' do
      it 'should retry three times' do
        expect(vm_object).to receive(:PowerOffVM_Task).and_throw(:powerofffailed, 'failed').exactly(3).times

        expect{ subject.destroy_vm_and_log(vmname, vm_object, pool, data_ttl) }.to raise_error(/failed/)
      end
    end
  end

  describe '#destroy_folder_and_children' do
    let(:data_ttl) { 1 }
    let(:config) {
      {
        redis: {
          'data_ttl' => data_ttl
        }
      }
    }
    let(:foldername) { 'pool1' }
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername }) }

    before(:each) do
      $config = config
    end

    context 'with an empty folder' do
      it 'should destroy the folder' do
        expect(subject).to_not receive(:destroy_vm_and_log)
        expect(subject).to receive(:destroy_folder).with(folder_object).and_return(nil)

        subject.destroy_folder_and_children(folder_object)
      end
    end

    context 'with a folder containing vms' do
      let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname }) }
      before(:each) do
        folder_object.childEntity << vm_object
      end

      it 'should destroy the vms' do
        allow(subject).to receive(:destroy_vm_and_log).and_return(nil)
        allow(subject).to receive(:destroy_folder).and_return(nil)
        expect(subject).to receive(:destroy_vm_and_log).with(vmname, vm_object, foldername, data_ttl)

        subject.destroy_folder_and_children(folder_object)
      end
    end

    it 'should raise any errors' do
      expect(subject).to receive(:destroy_folder).and_throw('mockerror')

      expect{ subject.destroy_folder_and_children(folder_object) }.to raise_error(/mockerror/)
    end
  end

  describe '#destroy_folder' do
    let(:foldername) { 'pool1' }
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername }) }
    let(:destroy_task) { mock_RbVmomi_VIM_Task() }

    before(:each) do
      allow(folder_object).to receive(:Destroy_Task).and_return(destroy_task)
      allow(destroy_task).to receive(:wait_for_completion)
    end

    it 'should destroy the folder' do
      expect(folder_object).to receive(:Destroy_Task).and_return(destroy_task)

      subject.destroy_folder(folder_object)
    end

    it 'should log that the folder is being destroyed' do
      expect(logger).to receive(:log).with('s', "[-] [#{foldername}] removing unconfigured folder")

      subject.destroy_folder(folder_object)
    end

    it 'should retry three times when failing' do
      expect(folder_object).to receive(:Destroy_Task).and_throw('mockerror').exactly(3).times

      expect{ subject.destroy_folder(folder_object) }.to raise_error(/mockerror/)
    end
  end

  describe '#purge_unconfigured_folders' do
    let(:folder_title) { 'folder1' }
    let(:base_folder) { 'dc1/vm/base' }
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => base_folder }) }
    let(:child_folder) { mock_RbVmomi_VIM_Folder({ :name => folder_title }) }
    let(:whitelist) { nil }
    let(:base_folders) { [ base_folder ] }
    let(:configured_folders) { { folder_title => base_folder } }
    let(:folder_children) { [ folder_title => child_folder ] }
    let(:empty_list) { [] }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'with an empty folder' do
      it 'should not attempt to destroy any folders' do
        expect(subject).to receive(:get_folder_children).with(base_folder, connection).and_return(empty_list)
        expect(subject).to_not receive(:destroy_folder_and_children)

        subject.purge_unconfigured_folders(base_folders, configured_folders, whitelist)
      end
    end

    it 'should retrieve the folder children' do
      expect(subject).to receive(:get_folder_children).with(base_folder, connection).and_return(folder_children)
      allow(subject).to receive(:folder_configured?).and_return(true)

      subject.purge_unconfigured_folders(base_folders, configured_folders, whitelist)
    end

    context 'with a folder that is not configured' do
      before(:each) do
        expect(subject).to receive(:get_folder_children).with(base_folder, connection).and_return(folder_children)
        allow(subject).to receive(:folder_configured?).and_return(false)
      end

      it 'should destroy the folder and children' do
        expect(subject).to receive(:destroy_folder_and_children).with(child_folder).and_return(nil)

        subject.purge_unconfigured_folders(base_folders, configured_folders, whitelist)
      end
    end

    it 'should raise any errors' do
      expect(subject).to receive(:get_folder_children).and_throw('mockerror')

      expect{ subject.purge_unconfigured_folders(base_folders, configured_folders, whitelist) }.to raise_error(/mockerror/)
    end
  end

  describe '#get_folder_children' do
    let(:base_folder) { 'dc1/vm/base' }
    let(:base_folder_object) { mock_RbVmomi_VIM_Folder({ :name => base_folder }) }
    let(:foldername) { 'folder1' }
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername }) }
    let(:folder_return) { [ { foldername => folder_object } ] }

    before(:each) do
      base_folder_object.childEntity << folder_object
    end

    it 'should return an array of configured folder hashes' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_return(base_folder_object)

      result = subject.get_folder_children(foldername, connection)

      expect(result).to eq(folder_return)
    end

    it 'should raise any errors' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_throw('mockerror')

      expect{ subject.get_folder_children(foldername, connection) }.to raise_error(/mockerror/)
    end
  end

  describe '#vms_in_pool' do
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => 'pool1'}) }
    let(:pool_config) { config[:pools][0] }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'Given a pool folder that is missing' do
      before(:each) do
        expect(subject).to receive(:find_vm_folder).with(poolname,connection).and_return(nil)
      end

      it 'should get a connection' do
        expect(subject).to receive(:connect_to_vsphere).and_return(connection)

        subject.vms_in_pool(poolname)
      end

      it 'should return an empty array' do
        result = subject.vms_in_pool(poolname)

        expect(result).to eq([])
      end
    end

    context 'Given an empty pool folder' do
      before(:each) do
        expect(subject).to receive(:find_vm_folder).with(poolname,connection).and_return(folder_object)
      end

      it 'should get a connection' do
        expect(subject).to receive(:connect_to_vsphere).and_return(connection)

        subject.vms_in_pool(poolname)
      end

      it 'should return an empty array' do
        result = subject.vms_in_pool(poolname)

        expect(result).to eq([])
      end
    end

    context 'Given a pool folder with many VMs' do
      let(:expected_vm_list) {[
        { 'name' => 'vm1'},
        { 'name' => 'vm2'},
        { 'name' => 'vm3'}
      ]}
      before(:each) do
        expected_vm_list.each do |vm_hash|
          mock_vm = mock_RbVmomi_VIM_VirtualMachine({ :name => vm_hash['name'] })
          # Add the mocked VM to the folder
          folder_object.childEntity << mock_vm
        end

        expect(subject).to receive(:find_vm_folder).with(poolname,connection).and_return(folder_object)
      end

      it 'should get a connection' do
        expect(subject).to receive(:connect_to_vsphere).and_return(connection)

        subject.vms_in_pool(poolname)
      end

      it 'should list all VMs in the VM folder for the pool' do
        result = subject.vms_in_pool(poolname)

        expect(result).to eq(expected_vm_list)
      end
    end

    context 'given a pool folder with a folder and vms' do
      let(:expected_vm_list) {[
        { 'name' => 'vm1'},
        { 'name' => 'vm2'},
        { 'name' => 'vm3'}
      ]}
      let(:folder_object2) { mock_RbVmomi_VIM_Folder({ :name => 'pool2'}) }
      before(:each) do
        expected_vm_list.each do |vm_hash|
          mock_vm = mock_RbVmomi_VIM_VirtualMachine({ :name => vm_hash['name'] })
          # Add the mocked VM to the folder
          folder_object.childEntity << mock_vm
        end
        folder_object.childEntity << folder_object2
        expect(subject).to receive(:find_vm_folder).with(poolname,connection).and_return(folder_object)
      end

      it 'should return the vms without the folder' do
        result = subject.vms_in_pool(poolname)

        expect(result).to eq(expected_vm_list)
      end
    end
  end

  describe '#get_vm' do
    let(:vm_object) { nil }
    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      expect(subject).to receive(:find_vm).with(poolname,vmname,connection).and_return(vm_object)
    end

    context 'when VM does not exist' do
      it 'should return nil' do
        expect(subject.get_vm(poolname,vmname)).to be_nil
      end
    end

    context 'when VM exists but is missing information' do
      let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({
          :name => vmname,
        })
      }

      it 'should return a hash' do
        expect(subject.get_vm(poolname,vmname)).to be_kind_of(Hash)
      end

      it 'should return the VM name' do
        result = subject.get_vm(poolname,vmname)

        expect(result['name']).to eq(vmname)
      end

      ['hostname','boottime','powerstate'].each do |testcase|
        it "should return nil for #{testcase}" do
          result = subject.get_vm(poolname,vmname)

          expect(result[testcase]).to be_nil
        end
      end
    end

    context 'when VM exists and contains all information' do
      let(:vm_hostname) { "#{vmname}.demo.local" }
      let(:boot_time) { Time.now }
      let(:power_state) { 'MockPowerState' }

      let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({
          :name => vmname,
          :hostname => vm_hostname,
          :powerstate => power_state,
          :boottime => boot_time,
          # This path should match the folder in the mocked pool in the config above
          :path => [
            { :type => 'folder',     :name => 'Datacenters' },
            { :type => 'datacenter', :name => 'DC01' },
            { :type => 'folder',     :name => 'vm' },
            { :type => 'folder',     :name => 'Pooler' },
            { :type => 'folder',     :name => 'pool1'},
          ]
        })
      }
      let(:pool_info) { config[:pools][0]}

      it 'should return a hash' do
        expect(subject.get_vm(poolname,vmname)).to be_kind_of(Hash)
      end

      it 'should return the VM name' do
        result = subject.get_vm(poolname,vmname)

        expect(result['name']).to eq(vmname)
      end

      it 'should return the VM hostname' do
        result = subject.get_vm(poolname,vmname)

        expect(result['hostname']).to eq(vm_hostname)
      end

      it 'should return the template name' do
        result = subject.get_vm(poolname,vmname)

        expect(result['template']).to eq(pool_info['template'])
      end

      it 'should return the pool name' do
        result = subject.get_vm(poolname,vmname)

        expect(result['poolname']).to eq(pool_info['name'])
      end

      it 'should return the boot time' do
        result = subject.get_vm(poolname,vmname)

        expect(result['boottime']).to eq(boot_time)
      end

      it 'should return the powerstate' do
        result = subject.get_vm(poolname,vmname)

        expect(result['powerstate']).to eq(power_state)
      end

    end
  end

  describe '#create_vm' do
    let(:datacenter_object) { mock_RbVmomi_VIM_Datacenter({
      :datastores => ['datastore0'],
      :vmfolder_tree => {
        'Templates' => { :children => {
          'pool1' => { :object_type => 'vm', :name => 'pool1' },
        }},
        'Pooler' => { :children => {
          'pool1' => nil,
        }},
      },
      :hostfolder_tree => {
        'cluster1' =>  {:object_type => 'compute_resource'},
      }
    })
    }

    let(:clone_vm_task) { mock_RbVmomi_VIM_Task() }
    let(:new_vm_object)  { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname }) }
    let(:new_template_object)  { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname }) }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(connection.serviceInstance).to receive(:find_datacenter).and_return(datacenter_object)
    end

    context 'Given an invalid pool name' do
      it 'should raise an error' do
        expect{ subject.create_vm('missing_pool', vmname) }.to raise_error(/missing_pool does not exist/)
      end
    end

    context 'Given an invalid template path in the pool config' do
      before(:each) do
        config[:pools][0]['template'] = 'bad_template'
      end

      it 'should raise an error' do
        expect{ subject.create_vm(poolname, vmname) }.to raise_error(/did not specify a full path for the template/)
      end
    end

    context 'Given a template that starts with /' do
      before(:each) do
        config[:pools][0]['template'] = '/bad_template'
      end

      it 'should raise an error' do
        expect{ subject.create_vm(poolname, vmname) }.to raise_error(/did not specify a full path for the template/)
      end
    end

    context 'Given a template that ends with /' do
      before(:each) do
        config[:pools][0]['template'] = 'bad_template/'
      end

      it 'should raise an error' do
        expect{ subject.create_vm(poolname, vmname) }.to raise_error(/did not specify a full path for the template/)
      end
    end

    context 'Given a template VM that does not exist' do
      before(:each) do
        config[:pools][0]['template'] = 'Templates/missing_template'
        expect(subject).to receive(:find_template_vm).and_raise("specifies a template VM of #{vmname} which does not exist")
      end

      it 'should raise an error' do
        expect{ subject.create_vm(poolname, vmname) }.to raise_error(/specifies a template VM of .+ which does not exist/)
      end
    end

    context 'when create_vm_folder returns nil' do
      before(:each) do
        allow(subject).to receive(:find_template_vm).and_return(new_template_object)
        expect(subject).to receive(:find_vm_folder).and_return(nil)
      end

      it 'should raise an error' do
        expect{ subject.create_vm(poolname, vmname) }.to raise_error(ArgumentError)
      end
    end

    context 'Given a successful creation' do
      let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => 'pool1'}) }
      before(:each) do
        template_vm = new_template_object
        allow(subject).to receive(:find_template_vm).and_return(new_template_object)
        allow(template_vm).to receive(:CloneVM_Task).and_return(clone_vm_task)
        allow(clone_vm_task).to receive(:wait_for_completion).and_return(new_vm_object)
        allow(subject).to receive(:find_vm_folder).and_return(folder_object)
      end

      it 'should return a hash' do
        result = subject.create_vm(poolname, vmname)

        expect(result.is_a?(Hash)).to be true
      end

      it 'should use the appropriate Create_VM spec' do
        template_vm = new_template_object
        expect(template_vm).to receive(:CloneVM_Task)
          .with(create_vm_spec(vmname,'pool1','datastore0'))
          .and_return(clone_vm_task)

        subject.create_vm(poolname, vmname)
      end

      it 'should have the new VM name' do
        result = subject.create_vm(poolname, vmname)

        expect(result['name']).to eq(vmname)
      end
    end
  end

  describe '#set_network_device' do
    let(:datacenter_object) { mock_RbVmomi_VIM_Datacenter({
      :datastores => ['datastore0'],
      :networks => ['network0'],
    })
    }
    let(:template_vm_network_device)  { mock_RbVmomi_VIM_VirtualVmxnet3() }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(connection.serviceInstance).to receive(:find_datacenter).and_return(datacenter_object)
    end

    context 'Given an invalid network name' do
      network_name = "invalid_network"

      it 'should raise an error' do
        expect { subject.set_network_device("datacenter_name", template_vm_network_device, network_name, connection)}.to raise_error(/Cannot find network/)
      end
    end

    context 'Given a valid network name' do
      network_name = "network0"
      it 'should return the network device' do
        result = subject.set_network_device("datacenter_name", template_vm_network_device, network_name, connection)
        expect(result).to be_instance_of(RbVmomi::VIM::VirtualVmxnet3)
        expect(result.deviceInfo).to be_instance_of(RbVmomi::VIM::Description)
        expect(result.deviceInfo.summary).to eq('network0')
        expect(result.backing).to be_instance_of(RbVmomi::VIM::VirtualEthernetCardNetworkBackingInfo)
        expect(result.backing.network.is_a?(RbVmomi::VIM::Network)).to be true
        expect(result.backing.network.name).to eq('network0')
        expect(result.connectable).to be_instance_of(RbVmomi::VIM::VirtualDeviceConnectInfo)
        expect(result.addressType).to eq('assigned')
      end
    end
  end

  describe '#create_disk' do
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname }) }
    let(:datastorename) { 'datastore0' }
    let(:disk_size) { 10 }
    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(vm_object)
    end

    context 'Given an invalid pool name' do
      it 'should raise an error' do
        expect{ subject.create_disk('missing_pool',vmname,disk_size) }.to raise_error(/missing_pool does not exist/)
      end
    end

    context 'Given a missing datastore in the pool config' do
      before(:each) do
        config[:pools][0]['datastore'] = nil
      end

      it 'should raise an error' do
        expect{ subject.create_disk(poolname,vmname,disk_size) }.to raise_error(/does not have a datastore defined/)
      end
    end

    context 'when VM does not exist' do
      before(:each) do
        expect(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(nil)
      end

      it 'should raise an error' do
        expect{ subject.create_disk(poolname,vmname,disk_size) }.to raise_error(/VM #{vmname} .+ does not exist/)
      end
    end

    context 'when adding the disk raises an error' do
      before(:each) do
        expect(subject).to receive(:add_disk).and_raise(RuntimeError,'Mock Disk Error')
      end

      it 'should raise an error' do
        expect{ subject.create_disk(poolname,vmname,disk_size) }.to raise_error(/Mock Disk Error/)
      end
    end

    context 'when adding the disk succeeds' do
      before(:each) do
        expect(subject).to receive(:add_disk).with(vm_object, disk_size, datastorename, connection, datacenter_name)
      end

      it 'should return true' do
        expect(subject.create_disk(poolname,vmname,disk_size)).to be true
      end
    end
  end

  describe '#create_snapshot' do
    let(:snapshot_task) { mock_RbVmomi_VIM_Task() }
    let(:snapshot_name) { 'snapshot' }
    let(:snapshot_tree) {{}}
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname, :snapshot_tree => snapshot_tree }) }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(subject).to receive(:find_vm).with(poolname, vmname,connection).and_return(vm_object)
    end

    context 'when VM does not exist' do
      before(:each) do
        expect(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(nil)
      end

      it 'should raise an error' do
        expect{ subject.create_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/VM #{vmname} .+ does not exist/)
      end
    end

    context 'when snapshot already exists' do
      let(:snapshot_object) { mock_RbVmomi_VIM_VirtualMachineSnapshot() }
      let(:snapshot_tree) { { snapshot_name => { :ref => snapshot_object } } }

      it 'should raise an error' do
        expect{ subject.create_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/Snapshot #{snapshot_name} .+ already exists /)
      end
    end

    context 'when snapshot raises an error' do
      before(:each) do
        expect(vm_object).to receive(:CreateSnapshot_Task).and_raise(RuntimeError,'Mock Snapshot Error')
      end

      it 'should raise an error' do
        expect{ subject.create_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/Mock Snapshot Error/)
      end
    end

    context 'when snapshot succeeds' do
      before(:each) do
        expect(vm_object).to receive(:CreateSnapshot_Task)
          .with(create_snapshot_spec(snapshot_name))
          .and_return(snapshot_task)
        expect(snapshot_task).to receive(:wait_for_completion).and_return(nil)
      end

      it 'should return true' do
        expect(subject.create_snapshot(poolname,vmname,snapshot_name)).to be true
      end
    end
  end

  describe '#revert_snapshot' do
    let(:snapshot_task) { mock_RbVmomi_VIM_Task() }
    let(:snapshot_name) { 'snapshot' }
    let(:snapshot_tree) { { snapshot_name => { :ref => snapshot_object } } }
    let(:snapshot_object) { mock_RbVmomi_VIM_VirtualMachineSnapshot() }
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname, :snapshot_tree => snapshot_tree }) }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(subject).to receive(:find_vm).with(poolname,vmname,connection).and_return(vm_object)
    end

    context 'when VM does not exist' do
      before(:each) do
        expect(subject).to receive(:find_vm).with(poolname,vmname,connection).and_return(nil)
      end

      it 'should raise an error' do
        expect{ subject.revert_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/VM #{vmname} .+ does not exist/)
      end
    end

    context 'when snapshot does not exist' do
      let(:snapshot_tree) {{}}

      it 'should raise an error' do
        expect{ subject.revert_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/Snapshot #{snapshot_name} .+ does not exist /)
      end
    end

    context 'when revert to snapshot raises an error' do
      before(:each) do
        expect(snapshot_object).to receive(:RevertToSnapshot_Task).and_raise(RuntimeError,'Mock Snapshot Error')
      end

      it 'should raise an error' do
        expect{ subject.revert_snapshot(poolname,vmname,snapshot_name) }.to raise_error(/Mock Snapshot Error/)
      end
    end

    context 'when revert to snapshot succeeds' do
      before(:each) do
        expect(snapshot_object).to receive(:RevertToSnapshot_Task).and_return(snapshot_task)
        expect(snapshot_task).to receive(:wait_for_completion).and_return(nil)
      end

      it 'should return true' do
        expect(subject.revert_snapshot(poolname,vmname,snapshot_name)).to be true
      end
    end
  end

  describe '#destroy_vm' do
    let(:power_off_task) { mock_RbVmomi_VIM_Task() }
    let(:destroy_task) { mock_RbVmomi_VIM_Task() }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'Given a missing VM name' do
      before(:each) do
        expect(subject).to receive(:find_vm).and_return(nil)
      end

      it 'should return true' do
        expect(subject.destroy_vm(poolname, 'missing_vm')).to be true
      end
    end

    context 'Given a powered on VM' do
      let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({
          :name => vmname,
          :powerstate => 'poweredOn',
        })
      }

      before(:each) do
        expect(subject).to receive(:find_vm).and_return(vm_object)
        allow(vm_object).to receive(:PowerOffVM_Task).and_return(power_off_task)
        allow(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        allow(power_off_task).to receive(:wait_for_completion)
        allow(destroy_task).to receive(:wait_for_completion)
      end

      it 'should call PowerOffVM_Task on the VM' do
        expect(vm_object).to receive(:PowerOffVM_Task).and_return(power_off_task)

        subject.destroy_vm(poolname, vmname)
      end

      it 'should call Destroy_Task on the VM' do
        expect(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        subject.destroy_vm(poolname, vmname)
      end

      it 'should return true' do
        expect(subject.destroy_vm(poolname, vmname)).to be true
      end
    end

    context 'Given a powered off VM' do
      let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({
          :name => vmname,
          :powerstate => 'poweredOff',
        })
      }

      before(:each) do
        expect(subject).to receive(:find_vm).and_return(vm_object)
        allow(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        allow(destroy_task).to receive(:wait_for_completion)
      end

      it 'should not call PowerOffVM_Task on the VM' do
        expect(vm_object).to receive(:PowerOffVM_Task).exactly(0).times

        subject.destroy_vm(poolname, vmname)
      end

      it 'should call Destroy_Task on the VM' do
        expect(vm_object).to receive(:Destroy_Task).and_return(destroy_task)

        subject.destroy_vm(poolname, vmname)
      end

      it 'should return true' do
        expect(subject.destroy_vm(poolname, vmname)).to be true
      end
    end
  end

  describe '#vm_ready?' do
    let(:domain) { nil }
    context 'When a VM is ready' do
      before(:each) do
        expect(subject).to receive(:open_socket).with(vmname, domain)
      end

      it 'should return true' do
        expect(subject.vm_ready?(poolname,vmname)).to be true
      end
    end

    context 'When a VM is ready but the pool does not exist' do
      # TODO not sure how to handle a VM that is passed in but
      # not located in the pool.  Is that ready or not?
      before(:each) do
        expect(subject).to receive(:open_socket).with(vmname, domain)
      end

      it 'should return true' do
        expect(subject.vm_ready?('missing_pool',vmname)).to be true
      end
    end

    context 'When an error occurs connecting to the VM' do
      # TODO not sure how to handle a VM that is passed in but
      # not located in the pool.  Is that ready or not?
      before(:each) do
        expect(subject).to receive(:open_socket).and_raise(RuntimeError,'MockError')
      end

      it 'should return false' do
        expect(subject.vm_ready?(poolname,vmname)).to be false
      end
    end
  end

  describe '#vm_exists?' do
    it 'should return true when get_vm returns an object' do
      allow(subject).to receive(:get_vm).with(poolname,vmname).and_return(mock_RbVmomi_VIM_VirtualMachine({ :name => vmname }))

      expect(subject.vm_exists?(poolname,vmname)).to eq(true)
    end

    it 'should return false when get_vm returns nil' do
      allow(subject).to receive(:get_vm).with(poolname,vmname).and_return(nil)

      expect(subject.vm_exists?(poolname,vmname)).to eq(false)
    end
  end

  # vSphere helper methods
  describe '#get_target_datacenter_from_config' do
    let(:pool_dc) { 'PoolDC'}
    let(:provider_dc) { 'ProvDC'}

    context 'when not specified' do
      let(:config) { YAML.load(<<-EOT
---
:config:
:providers:
  :vsphere:
    server: "vcenter.domain.local"
    username: "vcenter_user"
    password: "vcenter_password"
:pools:
  - name: '#{poolname}'
EOT
        )
      }
      it 'returns nil' do
        expect(subject.get_target_datacenter_from_config(poolname)).to be_nil
      end
    end

    context 'when specified only in the pool' do
      let(:config) { YAML.load(<<-EOT
---
:config:
:providers:
  :vsphere:
    server: "vcenter.domain.local"
    username: "vcenter_user"
    password: "vcenter_password"
:pools:
  - name: '#{poolname}'
    datacenter: '#{pool_dc}'
EOT
        )
      }
      it 'returns the pool datacenter' do
        expect(subject.get_target_datacenter_from_config(poolname)).to eq(pool_dc)
      end
    end

    context 'when specified only in the provider' do
      let(:config) { YAML.load(<<-EOT
---
:config:
:providers:
  :vsphere:
    server: "vcenter.domain.local"
    username: "vcenter_user"
    password: "vcenter_password"
    datacenter: '#{provider_dc}'
:pools:
  - name: '#{poolname}'
EOT
        )
      }
      it 'returns the provider datacenter' do
        expect(subject.get_target_datacenter_from_config(poolname)).to eq(provider_dc)
      end
    end

    context 'when specified in the provider and pool' do
      let(:config) { YAML.load(<<-EOT
---
:config:
:providers:
  :vsphere:
    server: "vcenter.domain.local"
    username: "vcenter_user"
    password: "vcenter_password"
    datacenter: '#{provider_dc}'
:pools:
  - name: '#{poolname}'
    datacenter: '#{pool_dc}'
EOT
        )
      }
      it 'returns the pool datacenter' do
        expect(subject.get_target_datacenter_from_config(poolname)).to eq(pool_dc)
      end
    end
  end

  # vSphere helper methods
  describe '#ensured_vsphere_connection' do
    let(:config) { YAML.load(<<-EOT
---
:config:
:providers:
  :vsphere:
    # Drop the connection pool timeout way down for spec tests so they fail fast
    connection_pool_timeout: 1
    connection_pool_size: 1
:pools:
EOT
      )
    }
    let(:connection1) { mock_RbVmomi_VIM_Connection(connection_options) }
    let(:connection2) { mock_RbVmomi_VIM_Connection(connection_options) }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection1)
    end

    # This is to ensure that the pool_size of 1 is in effect
    it 'should return the same connection object when calling the pool multiple times' do
      subject.connection_pool.with_metrics do |pool_object|
        expect(pool_object[:connection]).to be(connection1)
      end
      subject.connection_pool.with_metrics do |pool_object|
        expect(pool_object[:connection]).to be(connection1)
      end
      subject.connection_pool.with_metrics do |pool_object|
        expect(pool_object[:connection]).to be(connection1)
      end
    end

    context 'when the connection breaks' do
      before(:each) do
        # Emulate the connection state being good, then bad, then good again
        expect(subject).to receive(:vsphere_connection_ok?).and_return(true, false, true)
        expect(subject).to receive(:connect_to_vsphere).and_return(connection1, connection2)
      end

      it 'should restore the connection' do
        subject.connection_pool.with_metrics do |pool_object|
          # This line needs to be added to all instances of the connection_pool allocation
          connection = subject.ensured_vsphere_connection(pool_object)

          expect(connection).to be(connection1)
        end

        subject.connection_pool.with_metrics do |pool_object|
          connection = subject.ensured_vsphere_connection(pool_object)
          # The second connection would have failed.  This test ensures that a
          # new connection object was created.
          expect(connection).to be(connection2)
        end

        subject.connection_pool.with_metrics do |pool_object|
          connection = subject.ensured_vsphere_connection(pool_object)
          expect(connection).to be(connection2)
        end
      end
    end
  end

  describe '#connect_to_vsphere' do
    before(:each) do
      allow(RbVmomi::VIM).to receive(:connect).and_return(connection)
    end

    let (:credentials) { config[:providers][:vsphere] }

    context 'successful connection' do
      it 'should use the supplied credentials' do
        expect(RbVmomi::VIM).to receive(:connect).with({
          :host     => credentials['server'],
          :user     => credentials['username'],
          :password => credentials['password'],
          :insecure => credentials['insecure']
        }).and_return(connection)
        subject.connect_to_vsphere
      end

      it 'should honor the insecure setting' do
        config[:providers][:vsphere][:insecure] = true

        expect(RbVmomi::VIM).to receive(:connect).with({
          :host     => credentials['server'],
          :user     => credentials['username'],
          :password => credentials['password'],
          :insecure => true,
        }).and_return(connection)
        subject.connect_to_vsphere
      end

      it 'should default to an insecure connection' do
        config[:providers][:vsphere][:insecure] = nil

        expect(RbVmomi::VIM).to receive(:connect).with({
          :host     => credentials['server'],
          :user     => credentials['username'],
          :password => credentials['password'],
          :insecure => true
        }).and_return(connection)

        subject.connect_to_vsphere
      end

      it 'should return the connection object' do
        result = subject.connect_to_vsphere

        expect(result).to be(connection)
      end

      it 'should increment the connect.open counter' do
        expect(metrics).to receive(:increment).with('connect.open')
        subject.connect_to_vsphere
      end
    end

    context 'connection is initially unsuccessful' do
      before(:each) do
        # Simulate a failure and then success
        expect(RbVmomi::VIM).to receive(:connect).and_raise(RuntimeError,'MockError').ordered
        expect(RbVmomi::VIM).to receive(:connect).and_return(connection).ordered

        allow(subject).to receive(:sleep)
      end

      it 'should return the connection object' do
        result = subject.connect_to_vsphere

        expect(result).to be(connection)
      end

      it 'should increment the connect.fail and then connect.open counter' do
        expect(metrics).to receive(:increment).with('connect.fail').exactly(1).times
        expect(metrics).to receive(:increment).with('connect.open').exactly(1).times
        subject.connect_to_vsphere
      end
    end

    context 'connection is always unsuccessful' do
      before(:each) do
        allow(RbVmomi::VIM).to receive(:connect).and_raise(RuntimeError,'MockError')
        allow(subject).to receive(:sleep)
      end

      it 'should retry the connection attempt config.max_tries times' do
        expect(RbVmomi::VIM).to receive(:connect).exactly(config[:config]['max_tries']).times

        begin
          # Swallow any errors
          subject.connect_to_vsphere
        rescue
        end
      end

      it 'should increment the connect.fail counter config.max_tries times' do
        expect(metrics).to receive(:increment).with('connect.fail').exactly(config[:config]['max_tries']).times

        begin
          # Swallow any errors
          subject.connect_to_vsphere
        rescue
        end
      end

      [{:max_tries => 5, :retry_factor => 1},
      {:max_tries => 8, :retry_factor => 5},
      ].each do |testcase|
        context "Configuration set for max_tries of #{testcase[:max_tries]} and retry_facter of #{testcase[:retry_factor]}" do
          it "should sleep #{testcase[:max_tries] - 1} times between attempts with increasing timeout" do
            config[:config]['max_tries'] = testcase[:max_tries]
            config[:config]['retry_factor'] = testcase[:retry_factor]

            (1..testcase[:max_tries] - 1).each do |try|
              expect(subject).to receive(:sleep).with(testcase[:retry_factor] * try).ordered
            end

            begin
              # Swallow any errors
              subject.connect_to_vsphere
            rescue
            end
          end
        end
      end
    end
  end

  describe '#open_socket' do
    let(:TCPSocket) { double('tcpsocket') }
    let(:socket) { double('tcpsocket') }
    let(:hostname) { 'host' }
    let(:domain) { 'domain.local'}
    let(:default_socket) { 22 }

    before do
      expect(subject).not_to be_nil
      allow(socket).to receive(:close)
    end

    it 'opens socket with defaults' do
      expect(TCPSocket).to receive(:new).with(hostname,default_socket).and_return(socket)

      expect(subject.open_socket(hostname)).to eq(nil)
    end

    it 'yields the socket if a block is given' do
      expect(TCPSocket).to receive(:new).with(hostname,default_socket).and_return(socket)

      expect{ |socket| subject.open_socket(hostname,nil,nil,default_socket,&socket) }.to yield_control.exactly(1).times 
    end

    it 'closes the opened socket' do
      expect(TCPSocket).to receive(:new).with(hostname,default_socket).and_return(socket)
      expect(socket).to receive(:close)

      expect(subject.open_socket(hostname)).to eq(nil)
    end

    it 'opens a specific socket' do
      expect(TCPSocket).to receive(:new).with(hostname,80).and_return(socket)

      expect(subject.open_socket(hostname,nil,nil,80)).to eq(nil)
    end

    it 'uses a specific domain with the hostname' do
      expect(TCPSocket).to receive(:new).with("#{hostname}.#{domain}",default_socket).and_return(socket)

      expect(subject.open_socket(hostname,domain)).to eq(nil)
    end

    it 'raises error if host is not resolvable' do
      expect(TCPSocket).to receive(:new).with(hostname,default_socket).and_raise(SocketError,'getaddrinfo: No such host is known')

      expect { subject.open_socket(hostname,nil,1) }.to raise_error(SocketError)
    end

    it 'raises error if socket is not listening' do
      expect(TCPSocket).to receive(:new).with(hostname,default_socket).and_raise(SocketError,'No connection could be made because the target machine actively refused it')

      expect { subject.open_socket(hostname,nil,1) }.to raise_error(SocketError)
    end
  end

  describe '#get_vm_folder_path' do
    [
      { :path_description => 'Datacenters/DC01/vm/Pooler/pool1/vm1',
        :expected_path => 'Pooler/pool1',
        :vm_object_path => [
          { :type => 'folder',     :name => 'Datacenters' },
          { :type => 'datacenter', :name => 'DC01' },
          { :type => 'folder',     :name => 'vm' },
          { :type => 'folder',     :name => 'Pooler' },
          { :type => 'folder',     :name => 'pool1'},
        ],
      },
      { :path_description => 'Datacenters/DC01/vm/something/subfolder/pool/vm1',
        :expected_path => 'something/subfolder/pool',
        :vm_object_path => [
          { :type => 'folder',     :name => 'Datacenters' },
          { :type => 'datacenter', :name => 'DC01' },
          { :type => 'folder',     :name => 'vm' },
          { :type => 'folder',     :name => 'something' },
          { :type => 'folder',     :name => 'subfolder' },
          { :type => 'folder',     :name => 'pool'},
        ],
      },
      { :path_description => 'Datacenters/DC01/vm/vm1',
        :expected_path => '',
        :vm_object_path => [
          { :type => 'folder',     :name => 'Datacenters' },
          { :type => 'datacenter', :name => 'DC01' },
          { :type => 'folder',     :name => 'vm' },
        ],
      },
    ].each do |testcase|
      context "given a path of #{testcase[:path_description]}" do
        it "should return '#{testcase[:expected_path]}'" do
          vm_object = mock_RbVmomi_VIM_VirtualMachine({
            :name => 'vm1',
            :path => testcase[:vm_object_path],
          })
          expect(subject.get_vm_folder_path(vm_object)).to eq(testcase[:expected_path])
        end
      end
    end

    [
      { :path_description => 'a path missing a Datacenter',
        :vm_object_path => [
          { :type => 'folder',     :name => 'Datacenters' },
          { :type => 'folder',     :name => 'vm' },
          { :type => 'folder',     :name => 'Pooler' },
          { :type => 'folder',     :name => 'pool1'},
        ],
      },
      { :path_description => 'a path missing root VM folder',
        :vm_object_path => [
          { :type => 'folder',     :name => 'Datacenters' },
          { :type => 'datacenter', :name => 'DC01' },
        ],
      },
    ].each do |testcase|
      context "given #{testcase[:path_description]}" do
        it "should return nil" do
          vm_object = mock_RbVmomi_VIM_VirtualMachine({
            :name => 'vm1',
            :path => testcase[:vm_object_path],
          })
          expect(subject.get_vm_folder_path(vm_object)).to be_nil
        end
      end
    end
  end

  describe '#add_disk' do
    let(:datastorename) { 'datastore' }
    let(:disk_size) { 30 }
    let(:collectMultiple_response) { {} }

    let(:vm_scsi_controller) { mock_RbVmomi_VIM_VirtualSCSIController() }

    # Require at least one SCSI Controller
    let(:vm_object) {
      mock_vm = mock_RbVmomi_VIM_VirtualMachine({
        :name => vmname,
      })
      mock_vm.config.hardware.device << vm_scsi_controller

      mock_vm
    }

    # Require at least one DC with the required datastore
    let(:connection_options) {{
      :serviceContent => {
        :datacenters => [
          { :name => datacenter_name, :datastores => [datastorename] }
        ]
      }
    }}

    let(:create_virtual_disk_task) { mock_RbVmomi_VIM_Task() }
    let(:reconfig_vm_task) { mock_RbVmomi_VIM_Task() }

    before(:each) do
      # Mocking for find_vmdks
      allow(connection.serviceContent.propertyCollector).to receive(:collectMultiple).and_return(collectMultiple_response)

      # Mocking for creating the disk
      allow(connection.serviceContent.virtualDiskManager).to receive(:CreateVirtualDisk_Task) do |options|
        if options[:datacenter][:name] == datacenter_name
          create_virtual_disk_task
        end
      end
      allow(create_virtual_disk_task).to receive(:wait_for_completion).and_return(true)

      # Mocking for adding disk to the VM
      allow(vm_object).to receive(:ReconfigVM_Task).and_return(reconfig_vm_task)
      allow(reconfig_vm_task).to receive(:wait_for_completion).and_return(true)
    end

    context 'Successfully adding disk' do
      it 'should return true' do
        expect(subject.add_disk(vm_object,disk_size,datastorename,connection,datacenter_name)).to be true
      end

      it 'should request a disk of appropriate size' do
        expect(connection.serviceContent.virtualDiskManager).to receive(:CreateVirtualDisk_Task)
          .with(create_virtual_disk_with_size(disk_size))
          .and_return(create_virtual_disk_task)


        subject.add_disk(vm_object,disk_size,datastorename,connection,datacenter_name)
      end
    end

    context 'Requested disk size is 0' do
      it 'should raise an error' do
        expect(subject.add_disk(vm_object,0,datastorename,connection,datacenter_name)).to be false
      end
    end

    context 'No datastores or datastore missing' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name, :datastores => ['missing_datastore'] }
          ]
        }
      }}

      it 'should raise error' do
        expect{ subject.add_disk(vm_object,disk_size,datastorename,connection,datacenter_name) }.to raise_error(/does not exist/)
      end
    end

    context 'Multiple datacenters with multiple datastores' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => 'AnotherDC', :datastores => ['dc1','dc2'] },
            { :name => datacenter_name, :datastores => ['dc3',datastorename,'dc4'] },
          ]
        }
      }}

      it 'should return true' do
        expect(subject.add_disk(vm_object,disk_size,datastorename,connection,datacenter_name)).to be true
      end
    end

    context 'VM does not have a SCSI Controller' do
      let(:vm_object) {
        mock_vm = mock_RbVmomi_VIM_VirtualMachine({
          :name => vmname,
        })

        mock_vm
      }

      it 'should raise an error' do
        expect{ subject.add_disk(vm_object,disk_size,datastorename,connection,datacenter_name) }.to raise_error(NoMethodError)
      end
    end
  end

  describe '#create_clone_spec' do
    let(:relocate_spec) { mock_RbVmomi_VIM_VirtualMachineRelocateSpec({
      :datastore => 'datastore0',
      :diskMoveType => :moveChildMostDiskBacking,
      :pool => 'pool0'
    })
    }

    let(:config_spec) { mock_RbVmomi_VIM_VirtualMachineConfigSpec()}

    it 'should return the configured clone spec' do
      result = subject.create_clone_spec(relocate_spec, config_spec)
      expect(result.location.pool.name).to eq('pool0')
      expect(result.location.datastore.name).to eq('datastore0')
      expect(result.location.diskMoveType).to eq(:moveChildMostDiskBacking)
      expect(result.config.deviceChange.first[:operation]).to eq(:edit)
      expect(result.config.deviceChange.first[:device].is_a?(RbVmomi::VIM::VirtualVmxnet3)).to be true
    end
  end

  describe '#find_datastore' do
    let(:datastorename) { 'datastore' }
    let(:datastore_list) { [] }

    context 'No datastores in the datacenter' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name, :datastores => [] }
          ]
        }
      }}

      it 'should return nil if the datastore is not found' do
        result = subject.find_datastore(datastorename,connection,datacenter_name)
        expect(result).to be_nil
      end
    end

    context 'Many datastores in the datacenter' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name, :datastores => ['ds1','ds2',datastorename,'ds3'] }
          ]
        }
      }}

      it 'should return nil if the datastore is not found' do
        result = subject.find_datastore('missing_datastore',connection,datacenter_name)
        expect(result).to be_nil
      end

      it 'should find the datastore in the datacenter' do
        result = subject.find_datastore(datastorename,connection,datacenter_name)
        
        expect(result).to_not be_nil
        expect(result.is_a?(RbVmomi::VIM::Datastore)).to be true
        expect(result.name).to eq(datastorename)
      end
    end

    context 'Many datastores in many datacenters' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => 'AnotherDC', :datastores => ['ds1','ds2','ds3'] },
            { :name => datacenter_name, :datastores => ['ds3','ds4',datastorename,'ds5'] },
          ]
        }
      }}

      it 'should return nil if the datastore is not found' do
        result = subject.find_datastore(datastorename,connection,'AnotherDC')
        expect(result).to be_nil
      end

      it 'should find the datastore in the datacenter' do
        result = subject.find_datastore(datastorename,connection,datacenter_name)
        
        expect(result).to_not be_nil
        expect(result.is_a?(RbVmomi::VIM::Datastore)).to be true
        expect(result.name).to eq(datastorename)
      end
    end
  end

  describe '#find_device' do
    let(:devicename) { 'device1' }
    let(:vm_object) {
      mock_vm = mock_RbVmomi_VIM_VirtualMachine()
      mock_vm.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})
      mock_vm.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device2'})

      mock_vm
    }

    it 'should return a device if the device name matches' do
      result = subject.find_device(vm_object,devicename)

      expect(result.deviceInfo.label).to eq(devicename)
    end

    it 'should return nil if the device name does not match' do
      result = subject.find_device(vm_object,'missing_device')

      expect(result).to be_nil
    end
  end

  describe '#find_disk_controller' do
    let(:vm_object) {
      mock_vm = mock_RbVmomi_VIM_VirtualMachine()

      mock_vm
    }

    it 'should return nil when there are no devices' do
      result = subject.find_disk_controller(vm_object)

      expect(result).to be_nil
    end

    [0,1,14].each do |testcase|
      it "should return a device for a single VirtualSCSIController with #{testcase} attached disks" do
        mock_scsi = mock_RbVmomi_VIM_VirtualSCSIController()
        vm_object.config.hardware.device << mock_scsi
        vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})
        vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device2'})

        # Add the disks
        (1..testcase).each do
          vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualDisk({ :controllerKey => mock_scsi.key })
        end

        result = subject.find_disk_controller(vm_object)

        expect(result).to eq(mock_scsi)
      end
    end

    [15].each do |testcase|
      it "should return nil for a single VirtualSCSIController with #{testcase} attached disks" do
        mock_scsi = mock_RbVmomi_VIM_VirtualSCSIController()
        vm_object.config.hardware.device << mock_scsi
        vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})
        vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device2'})

        # Add the disks
        (1..testcase).each do
          vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualDisk({ :controllerKey => mock_scsi.key })
        end

        result = subject.find_disk_controller(vm_object)

        expect(result).to be_nil
      end
    end

    it 'should raise if a VirtualDisk is missing a controller' do
      # Note - Typically this is not possible as a VirtualDisk requires a controller (SCSI, PVSCSI or IDE)
      mock_scsi = mock_RbVmomi_VIM_VirtualDisk()
      vm_object.config.hardware.device << mock_scsi
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device2'})

      expect{subject.find_disk_controller(vm_object)}.to raise_error(NoMethodError)
    end
  end

  describe '#find_disk_devices' do
    let(:vm_object) {
      mock_vm = mock_RbVmomi_VIM_VirtualMachine()

      mock_vm
    }

    it 'should return empty hash when there are no devices' do
      result = subject.find_disk_devices(vm_object)

      expect(result).to eq({})
    end

    it 'should return empty hash when there are no VirtualSCSIController or VirtualDisk devices' do
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device2'})

      result = subject.find_disk_devices(vm_object)

      expect(result).to eq({})
    end

    it 'should return a device for a VirtualSCSIController device with no children' do
      mock_scsi = mock_RbVmomi_VIM_VirtualSCSIController()
      vm_object.config.hardware.device << mock_scsi
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})

      result = subject.find_disk_devices(vm_object)

      expect(result.count).to eq(1)
      expect(result[mock_scsi.key]).to_not be_nil
      expect(result[mock_scsi.key]['children']).to eq([])
      expect(result[mock_scsi.key]['device']).to eq(mock_scsi)
    end

    it 'should return a device for a VirtualDisk device' do
      mock_disk = mock_RbVmomi_VIM_VirtualDisk()
      vm_object.config.hardware.device << mock_disk
      vm_object.config.hardware.device << mock_RbVmomi_VIM_VirtualMachineDevice({:label => 'device1'})

      result = subject.find_disk_devices(vm_object)

      expect(result.count).to eq(1)
      expect(result[mock_disk.controllerKey]).to_not be_nil
      expect(result[mock_disk.controllerKey]['children'][0]).to eq(mock_disk)
    end

    it 'should return one device for many VirtualDisk devices on the same controller' do
      controller1Key = rand(2000)
      controller2Key = controller1Key + 1
      mock_disk1 = mock_RbVmomi_VIM_VirtualDisk({:controllerKey => controller1Key})
      mock_disk2 = mock_RbVmomi_VIM_VirtualDisk({:controllerKey => controller1Key})
      mock_disk3 = mock_RbVmomi_VIM_VirtualDisk({:controllerKey => controller2Key})

      vm_object.config.hardware.device << mock_disk2
      vm_object.config.hardware.device << mock_disk1
      vm_object.config.hardware.device << mock_disk3

      result = subject.find_disk_devices(vm_object)

      expect(result.count).to eq(2)

      expect(result[controller1Key]).to_not be_nil
      expect(result[controller2Key]).to_not be_nil

      expect(result[controller1Key]['children']).to contain_exactly(mock_disk1,mock_disk2)
      expect(result[controller2Key]['children']).to contain_exactly(mock_disk3)
    end
  end

  describe '#find_disk_unit_number' do
    let(:vm_object) {
      mock_vm = mock_RbVmomi_VIM_VirtualMachine()

      mock_vm
    }
    let(:controller) { mock_RbVmomi_VIM_VirtualSCSIController() }

    it 'should return 0 when there are no devices' do
      result = subject.find_disk_unit_number(vm_object,controller)

      expect(result).to eq(0)
    end

    context 'with a single SCSI Controller' do
      before(:each) do
        vm_object.config.hardware.device << controller
      end

      it 'should return 1 when the host bus controller is at 0' do
        controller.scsiCtlrUnitNumber = 0

        result = subject.find_disk_unit_number(vm_object,controller)

        expect(result).to eq(1)
      end

      it 'should return the next lowest id when disks are attached' do
        expected_id = 9
        controller.scsiCtlrUnitNumber = 0

        (1..expected_id-1).each do |disk_id|
          mock_disk = mock_RbVmomi_VIM_VirtualDisk({
            :controllerKey => controller.key,
            :unitNumber => disk_id,
          })
          vm_object.config.hardware.device << mock_disk
        end
        result = subject.find_disk_unit_number(vm_object,controller)

        expect(result).to eq(expected_id)
      end

      it 'should return nil when there are no spare units' do
        controller.scsiCtlrUnitNumber = 0

        (1..15).each do |disk_id|
          mock_disk = mock_RbVmomi_VIM_VirtualDisk({
            :controllerKey => controller.key,
            :unitNumber => disk_id,
          })
          vm_object.config.hardware.device << mock_disk
        end
        result = subject.find_disk_unit_number(vm_object,controller)

        expect(result).to eq(nil)
      end
    end
  end

  describe '#find_vm_folder' do
    let(:foldername) { 'folder'}

    context 'with no folder hierarchy' do

      it 'should return nil if the folder is not found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)
        expect(subject.find_vm_folder(poolname,connection)).to be_nil
      end
    end

    context 'with a single layer folder hierarchy' do
      let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername}) }

      it 'should return the folder when found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
        result = subject.find_vm_folder(poolname,connection)
        expect(result.name).to eq(foldername)
      end

      it 'should return nil if the folder is not found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)
        expect(subject.find_vm_folder(poolname,connection)).to be_nil
      end
    end

    context 'with a single layer folder hierarchy in many datacenters' do
      let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername}) }

      it 'should return the folder when found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
        result = subject.find_vm_folder(poolname,connection)
        expect(result.name).to eq(foldername)
      end

      it 'should return nil if the folder is not found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)
        expect(subject.find_vm_folder(poolname,connection)).to be_nil
      end
    end

    context 'with a multi layer folder hierarchy' do
      let(:foldername) { 'folder2/folder4/folder' }
      let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => foldername}) }

      it 'should return the folder when found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(folder_object)
        allow(folder_object).to receive(:class).and_return(RbVmomi::VIM::Folder)
        result = subject.find_vm_folder(poolname,connection)
        expect(result.name).to eq(foldername)
      end

      it 'should return nil if the folder is not found' do
        allow(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)
        expect(subject.find_vm_folder(poolname,connection)).to be_nil
      end
    end
  end

  describe '#get_host_utilization' do
    let(:cpu_model) { 'vendor line type sku v4 speed' }
    let(:model) { 'v4' }
    let(:different_model) { 'different_model' }
    let(:limit) { 75 }
    let(:default_limit) { 90 }

    context "host with a different model" do
      let(:host) { mock_RbVmomi_VIM_HostSystem() }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,different_model,limit)).to be_nil
      end
    end

    context "host in maintenance mode" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :maintenance_mode => true,
        })
      }
      it 'should return nil' do
        host.runtime.inMaintenanceMode = true

        expect(subject.get_host_utilization(host,model,limit)).to be_nil
      end
    end

    context "host with status of not green" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_status => 'purple_alert',
        })
      }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,model,limit)).to be_nil
      end
    end

    context "host with configuration issue" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :config_issue => 'No quickstats',
      })
      }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,model,limit)).to be_nil
      end
    end

    # CPU utilization
    context "host which exceeds limit in CPU utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => 100,
        :overall_memory_usage => 1,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,model,limit)).to be_nil
      end
    end

    context "host which exceeds default limit in CPU utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => default_limit + 1.0,
        :overall_memory_usage => 1,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,model)).to be_nil
      end
    end

    context "host which does not exceed default limit in CPU utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => default_limit,
        :overall_memory_usage => 1,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should not return nil' do
        expect(subject.get_host_utilization(host,model)).to_not be_nil
      end
    end

    # Memory utilization
    context "host which exceeds limit in Memory utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => 1,
        :overall_memory_usage => 100,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should return nil' do
        # Set the Memory Usage to 100%
        expect(subject.get_host_utilization(host,model,limit)).to be_nil
      end
    end

    context "host which exceeds default limit in Memory utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => 1,
        :overall_memory_usage => default_limit + 1.0,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should return nil' do
        expect(subject.get_host_utilization(host,model)).to be_nil
      end
    end

    context "host which does not exceed default limit in Memory utilization" do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => 1,
        :overall_memory_usage => default_limit,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should not return nil' do
        expect(subject.get_host_utilization(host,model)).to_not be_nil
      end
    end

    context "host which does not exceed limits" do
      # Set CPU to 10%
      # Set Memory to 20%
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :overall_cpu_usage => 10,
        :overall_memory_usage => 20,
        :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
        })
      }
      it 'should return the sum of CPU and Memory utilization' do
        expect(subject.get_host_utilization(host,model,limit)[0]).to eq(10)
      end

      it 'should return the host' do
        expect(subject.get_host_utilization(host,model,limit)[1]).to eq(host)
      end
    end

    context 'host with no quickstats' do
      let(:host) { mock_RbVmomi_VIM_HostSystem({
        :cpu_speed => 100,
        :num_cores_per_cpu => 1,
        :num_cpu => 1,
        :memory_size => 100.0 * 1024 * 1024
        })
      }
      before(:each) do
        host.summary.quickStats.overallCpuUsage = nil
      end

      it 'should return nil' do
        result = subject.get_host_utilization(host,model,limit)
        expect(result).to be nil
      end
    end
  end

  describe '#host_has_cpu_model?' do
    let(:cpu_model) { 'vendor line type sku v4 speed' }
    let(:model) { 'v4' }
    let(:different_model) { 'different_model' }
    let(:host) { mock_RbVmomi_VIM_HostSystem({
      :cpu_model => cpu_model,
      })
    }

    it 'should return true if the model matches' do
      expect(subject.host_has_cpu_model?(host,model)).to eq(true)
    end

    it 'should return false if the model is different' do
      expect(subject.host_has_cpu_model?(host,different_model)).to eq(false)
    end
  end

  describe '#get_host_cpu_arch_version' do
    let(:cpu_model) { 'vendor line type sku v4 speed' }
    let(:model) { 'v4' }
    let(:different_model) { 'different_model' }
    let(:host) { mock_RbVmomi_VIM_HostSystem({
      :cpu_model => cpu_model,
      :num_cpu => 2,
      })
    }

    it 'should return the fifth element in the string delimited by spaces' do
      expect(subject.get_host_cpu_arch_version(host)).to eq(model)
    end

    it 'should use the description of the first CPU' do
      host.hardware.cpuPkg[0].description = 'vendor line type sku v6 speed'
      expect(subject.get_host_cpu_arch_version(host)).to eq('v6')
    end
  end

  describe '#cpu_utilization_for' do
    [{ :cpu_usage => 10.0,
      :core_speed => 10.0,
      :num_cores => 2,
      :expected_value => 50.0,
    },
    { :cpu_usage => 10.0,
      :core_speed => 10.0,
      :num_cores => 4,
      :expected_value => 25.0,
    },
    { :cpu_usage => 14.0,
      :core_speed => 12.0,
      :num_cores => 5,
      :expected_value => 23.0 + 1.0/3.0,
    },
    ].each do |testcase|
      context "CPU Usage of #{testcase[:cpu_usage]}MHz with #{testcase[:num_cores]} x #{testcase[:core_speed]}MHz cores" do
        it "should be #{testcase[:expected_value]}%" do
          host = mock_RbVmomi_VIM_HostSystem({
            :num_cores_per_cpu => testcase[:num_cores],
            :cpu_speed         => testcase[:core_speed],
            :overall_cpu_usage => testcase[:cpu_usage],
          })

          expect(subject.cpu_utilization_for(host)).to eq(testcase[:expected_value])
        end
      end
    end
  end

  describe '#memory_utilization_for' do
    [{ :memory_usage_gigbytes => 10.0,
      :memory_size_bytes => 10.0 * 1024 * 1024,
      :expected_value => 100.0,
    },
    { :memory_usage_gigbytes => 15.0,
      :memory_size_bytes => 25.0 * 1024 * 1024,
      :expected_value => 60.0,
    },
    { :memory_usage_gigbytes => 9.0,
      :memory_size_bytes => 31.0 * 1024 * 1024,
      :expected_value => 29.03225806451613,
    },
    ].each do |testcase|
      context "Memory Usage of #{testcase[:memory_usage_gigbytes]}GBytes with #{testcase[:memory_size_bytes]}Bytes of total memory" do
        it "should be #{testcase[:expected_value]}%" do
          host = mock_RbVmomi_VIM_HostSystem({
            :memory_size          => testcase[:memory_size_bytes],
            :overall_memory_usage => testcase[:memory_usage_gigbytes],
          })

          expect(subject.memory_utilization_for(host)).to eq(testcase[:expected_value])
        end
      end
    end
  end

  describe '#select_target_hosts' do
    let(:target) { {} }
    let(:cluster) { 'cluster1' }
    let(:missing_cluster_name) { 'missing_cluster' }
    let(:datacenter) { 'dc1' }
    let(:architecture) { 'v3' }
    let(:host) { 'host1' }
    let(:hosts_hash) {
      {
        'hosts' => [host],
        'architectures' => {
          architecture => [host]
        }
      }
    }

    it 'returns a hash of the least used hosts by cluster and architecture' do
      expect(subject).to receive(:find_least_used_hosts).and_return(hosts_hash)

      subject.select_target_hosts(target, cluster, datacenter)
      expect(target["#{datacenter}_#{cluster}"]).to eq(hosts_hash)
    end

    context 'with a cluster specified that does not exist' do
      it 'raises an error' do
        expect(subject).to receive(:find_least_used_hosts).with(missing_cluster_name, datacenter, 100).and_raise("Cluster #{cluster} cannot be found")
        expect{subject.select_target_hosts(target, missing_cluster_name, datacenter)}.to raise_error(RuntimeError,/Cluster #{cluster} cannot be found/)
      end
    end
  end

  describe '#get_average_cluster_utilization' do
    let(:hosts) {
      [
        [60, 'host1'],
        [100, 'host2'],
        [200, 'host3']
      ]
    }
    it 'returns the average utilization for a given set of host utilizations assuming the first member of the list for each host is the utilization value' do
      expect(subject.get_average_cluster_utilization(hosts)).to eq(120)
    end
  end

  describe '#build_compatible_hosts_lists' do
    let(:host1) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST1' })}
    let(:host2) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST2' })}
    let(:host3) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST3' })}
    let(:architecture) { 'v4' }
    let(:percentage) { 100 }
    let(:hosts) {
      [
        [60, host1],
        [100, host2],
        [200, host3]
      ]
    }
    let(:result) {
      {
          architecture => ['HOST1','HOST2']
      }
    }

    it 'returns a hash of target host architecture versions containing lists of target hosts' do

      expect(subject.build_compatible_hosts_lists(hosts, percentage)).to eq(result)
    end
  end

  describe '#select_least_used_hosts' do
    let(:percentage) { 100 }
    let(:host1) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST1' })}
    let(:host2) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST2' })}
    let(:host3) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST3' })}
    let(:hosts) {
      [
        [60, host1],
        [100, host2],
        [200, host3]
      ]
    }
    let(:result) { ['HOST1','HOST2'] }
    it 'returns the percentage specified of the least used hosts in the cluster determined by selecting from less than or equal to average cluster utilization' do
      expect(subject.select_least_used_hosts(hosts, percentage)).to eq(result)
    end

    context 'when selecting 20 percent of hosts below average' do
      let(:percentage) { 20 }
      let(:result) { ['HOST1'] }

      it 'should return the result' do
        expect(subject.select_least_used_hosts(hosts, percentage)).to eq(result)
      end
    end

    it 'should raise' do
      expect{subject.select_least_used_hosts([], percentage)}.to raise_error(RuntimeError,/Provided hosts list to select_least_used_hosts is empty/)
    end
  end

  describe '#run_select_hosts' do
    let(:target) { {} }
    let(:cluster) { 'cluster1' }
    let(:missing_cluster_name) { 'missing_cluster' }
    let(:datacenter) { 'dc1' }
    let(:architecture) { 'v3' }
    let(:host) { 'host1' }
    let(:loop_delay) { 5 }
    let(:max_age) { 60 }
    let(:dc) { "#{datacenter}_#{cluster}" }
    let(:hosts_hash) {
      {
       dc => {
          'hosts' => [host],
          'architectures' => {
            architecture => [host]
          }
        }
      }
    }
    let(:config) { YAML.load(<<-EOT
---
:config:
  max_age: 60
:pools:
  - name: '#{poolname}'
    datacenter: '#{datacenter}'
    clone_target: '#{cluster}'
EOT
      )
    }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'target does not have key dc' do
      let(:hosts_hash) { { } }
      it 'should run select_target_hosts' do
        expect(subject).to receive(:select_target_hosts).with(hosts_hash, cluster, datacenter)
        subject.run_select_hosts(poolname, hosts_hash)
      end
    end

    context 'when check_time_finished is greater than max_age' do
      before(:each) do
        hosts_hash[dc]['check_time_finished'] = Time.now - (max_age + 10)
      end

      it 'should run select_target_hosts' do
        expect(subject).to receive(:select_target_hosts).with(hosts_hash, cluster, datacenter)
        subject.run_select_hosts(poolname, hosts_hash)
      end
    end

    context 'when check_time_finished is not greater than max_age' do
      before(:each) do
        hosts_hash[dc]['check_time_finished'] = Time.now - (max_age / 2)
      end

      it 'should not run select_target_hosts' do
        expect(subject).to_not receive(:select_target_hosts).with(hosts_hash, cluster, datacenter)
        subject.run_select_hosts(poolname, hosts_hash)
      end
    end

    context 'when hosts are being selected' do
      before(:each) do
        hosts_hash[dc]['checking'] = true
      end

      it 'should run wait_for_host_selection' do
        expect(subject).to receive(:wait_for_host_selection).with(dc, hosts_hash, loop_delay, max_age)
        subject.run_select_hosts(poolname, hosts_hash)
      end

    end

    context 'with no clone_target' do
      before(:each) do
        config[:pools][0].delete('clone_target')
      end

      it 'should raise an error' do
        expect{subject.run_select_hosts(poolname, hosts_hash)}.to raise_error(/cluster for pool #{poolname} cannot be identified/)
      end
    end

    context 'with no datacenter' do
      before(:each) do
        config[:pools][0].delete('datacenter')
      end

      it 'should raise an error' do
        expect{subject.run_select_hosts(poolname, hosts_hash)}.to raise_error(/datacenter for pool #{poolname} cannot be identified/)
      end
    end
  end

  describe '#wait_for_host_selection' do
    let(:datacenter) { 'dc1' }
    let(:cluster) { 'cluster1' }
    let(:dc) { "#{datacenter}_#{cluster}" }
    let(:maxloop) { 1 }
    let(:loop_delay) { 1 }
    let(:max_age) { 60 }
    let(:target) {
      {
        dc => { }
      }
    }

    context 'when target does not have key check_time_finished' do
      it 'should sleep for loop_delay maxloop times' do
        expect(subject).to receive(:sleep).with(loop_delay).once

        subject.wait_for_host_selection(dc, target, maxloop, loop_delay, max_age)
      end
    end

    context 'when target has dc and check_time_finished is greater than max_age' do
      before(:each) do
        target[dc]['check_time_finished'] = Time.now - (max_age + 10)
      end

      it 'should sleep for loop_delay maxloop times' do
        expect(subject).to receive(:sleep).with(loop_delay).once

        subject.wait_for_host_selection(dc, target, maxloop, loop_delay, max_age)
      end
    end

    context 'when target has dc and check_time_finished difference from now is less than max_age' do
      before(:each) do
        target[dc]['check_time_finished'] = Time.now - (max_age / 2)
      end

      it 'should not wait' do
        expect(subject).to_not receive(:sleep).with(loop_delay)

        subject.wait_for_host_selection(dc, target, maxloop, loop_delay, max_age)
      end
    end
  end

  describe '#select_next_host' do
    let(:cluster) { 'cluster1' }
    let(:datacenter) { 'dc1' }
    let(:architecture) { 'v3' }
    let(:host) { 'host1' }
    let(:loop_delay) { 5 }
    let(:max_age) { 60 }
    let(:dc) { "#{datacenter}_#{cluster}" }
    let(:hosts_hash) {
      {
       dc => {
          'hosts' => [host, 'host2'],
          'architectures' => {
            architecture => ['host3', 'host4']
          }
        }
      }
    }
    let(:config) { YAML.load(<<-EOT
---
:config:
  max_age: 60
:pools:
  - name: '#{poolname}'
    datacenter: '#{datacenter}'
    clone_target: '#{cluster}'
EOT
      )
    }

    context 'when host is requested' do
      it 'should return the first host' do
        result = subject.select_next_host(poolname, hosts_hash)
        expect(result).to eq(host)
      end

      it 'should return the second host if called twice' do
        subject.select_next_host(poolname, hosts_hash)
        result2 = subject.select_next_host(poolname, hosts_hash)
        expect(result2).to eq('host2')
      end
    end

    context 'when host and architecture are requested' do
      it 'should return the first host' do
        result = subject.select_next_host(poolname, hosts_hash, architecture)
        expect(result).to eq('host3')
      end

      it 'should return the second host if called twice' do
        subject.select_next_host(poolname, hosts_hash, architecture)
        result2 = subject.select_next_host(poolname, hosts_hash, architecture)
        expect(result2).to eq('host4')
      end
    end

    context 'with no hosts available' do
      before(:each) do
        hosts_hash[dc].delete('hosts')
        hosts_hash[dc].delete('architectures')
      end
      it 'should raise an error' do
        expect{subject.select_next_host(poolname, hosts_hash)}.to raise_error("there is no candidate in vcenter that meets all the required conditions, that the cluster has available hosts in a 'green' status, not in maintenance mode and not overloaded CPU and memory")
      end

      it 'should raise an error when selecting with architecture' do
        expect{subject.select_next_host(poolname, hosts_hash, architecture)}.to raise_error("there is no candidate in vcenter that meets all the required conditions, that the cluster has available hosts in a 'green' status, not in maintenance mode and not overloaded CPU and memory")
      end
    end

    context 'with no datacenter set for pool' do
      before(:each) do
        config[:pools][0].delete('datacenter')
      end

      it 'should raise an error' do
        expect{subject.select_next_host(poolname, hosts_hash)}.to raise_error("datacenter for pool #{poolname} cannot be identified")
      end
    end

    context 'with no clone_target set for pool' do
      before(:each) do
        config[:pools][0].delete('clone_target')
      end

      it 'should raise an error' do
        expect{subject.select_next_host(poolname, hosts_hash)}.to raise_error("cluster for pool #{poolname} cannot be identified")
      end
    end
  end

  describe '#vm_in_target?' do
    let(:parent_host) { 'host1' }
    let(:architecture) { 'v3' }
    let(:datacenter) { 'dc1' }
    let(:cluster) { 'cluster1' }
    let(:dc) { "#{datacenter}_#{cluster}" }
    let(:maxloop) { 1 }
    let(:loop_delay) { 1 }
    let(:max_age) { 60 }
    let(:target) {
      {
        dc => {
          'hosts' => [parent_host],
          'architectures' => {
            architecture => [parent_host]
          }
        }
      }
    }
    let(:config) { YAML.load(<<-EOT
---
:pools:
  - name: '#{poolname}'
    datacenter: '#{datacenter}'
    clone_target: '#{cluster}'
EOT
      )
    }

    it 'returns true when parent_host is in hosts' do
      result = subject.vm_in_target?(poolname, parent_host, architecture, target)
      expect(result).to be true
    end

    context 'with parent_host only in architectures' do
      before(:each) do
        target[dc]['hosts'] = ['host2']
      end

      it 'returns true when parent_host is in architectures' do
        result = subject.vm_in_target?(poolname, parent_host, architecture, target)
        expect(result).to be true
      end
    end

    it 'returns false when parent_host is not in hosts or architectures' do
      result = subject.vm_in_target?(poolname, 'host3', architecture, target)
      expect(result).to be false
    end

    context 'with no hosts key' do
      before(:each) do
        target[dc].delete('hosts')
      end

      it 'should raise an error' do
        expect{subject.vm_in_target?(poolname, parent_host, architecture, target)}.to raise_error("there is no candidate in vcenter that meets all the required conditions, that the cluster has available hosts in a 'green' status, not in maintenance mode and not overloaded CPU and memory")
      end
    end
  end

  describe '#get_vm_details' do
    let(:parent_host) { 'host1' }
    let(:host_object) { mock_RbVmomi_VIM_HostSystem({ :name => parent_host })}
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname })}
    let(:architecture) { 'v4' }
    let(:vm_details) {
      {
        'host_name' => parent_host,
        'object' => vm_object,
        'architecture' => architecture
      }
    }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    it 'returns nil when vm_object is not found' do
      expect(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(nil)
      result = subject.get_vm_details(poolname, vmname, connection)
      expect(result).to be nil
    end

    it 'raises an error when unable to determine parent_host' do
      expect(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(vm_object)
      expect{subject.get_vm_details(poolname, vmname, connection)}.to raise_error('Unable to determine which host the VM is running on')
    end

    context 'when it can find parent host' do
      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm_object.summary.runtime.host = host_object
      end

      it 'returns vm details hash' do
        expect(subject).to receive(:find_vm).with(poolname, vmname, connection).and_return(vm_object)
        result = subject.get_vm_details(poolname, vmname, connection)
        expect(result).to eq(vm_details)
      end
    end
  end

  describe '#migrate_vm' do
    let(:parent_host) { 'host1' }
    let(:new_host) { 'host2' }
    let(:datacenter) { 'dc1' }
    let(:architecture) { 'v4' }
    let(:cluster) { 'cluster1' }
    let(:vm_details) {
      {
        'host_name' => parent_host,
        'object' => vm_object,
        'architecture' => architecture
      }
    }
    let(:host_object) { mock_RbVmomi_VIM_HostSystem({ :name => parent_host })}
    let(:new_host_object) { mock_RbVmomi_VIM_HostSystem({ :name => new_host })}
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname })}
    let(:config) { YAML.load(<<-EOT
---
:config:
  migration_limit: 5
:pools:
  - name: '#{poolname}'
    datacenter: '#{datacenter}'
    clone_target: '#{cluster}'
EOT
      )
    }
    let(:dc) { "#{datacenter}_#{cluster}" }
    let(:provider_hosts) {
      {
        dc => {
          'hosts' => [new_host],
          'architectures' => {
            architecture => [new_host]
          },
          'check_time_finished' => Time.now
        }
      }
    }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'when vm should be migrated' do
      before(:each) do
        subject.connection_pool.with_metrics do |pool_object|
          expect(subject).to receive(:ensured_vsphere_connection).with(pool_object).and_return(connection)
          expect(subject).to receive(:get_vm_details).and_return(vm_details)
          expect(subject).to receive(:run_select_hosts).with(poolname, {})
          expect(subject).to receive(:vm_in_target?).and_return false
          expect(subject).to receive(:migration_enabled?).and_return true
          redis_connection_pool.with do |redis|
            redis.hset("vmpooler__vm__#{vmname}", 'checkout', Time.now)
          end
        end
        vm_object.summary.runtime.host = host_object
      end

      it 'logs a message' do
        expect(subject).to receive(:select_next_host).and_return(new_host)
        expect(subject).to receive(:find_host_by_dnsname).and_return(new_host_object)
        expect(subject).to receive(:migrate_vm_host).with(vm_object, new_host_object)
        expect(logger).to receive(:log).with('s', "[>] [#{poolname}] '#{vmname}' migrated from #{parent_host} to #{new_host} in 0.00 seconds")

        subject.migrate_vm(poolname, vmname)
      end

      it 'migrates a vm' do
        expect(subject).to receive(:migrate_vm_to_new_host).with(poolname, vmname, vm_details, connection)

        subject.migrate_vm(poolname, vmname)
      end
    end

    context 'current host is in the list of target hosts' do
      before(:each) do
        subject.connection_pool.with_metrics do |pool_object|
          expect(subject).to receive(:ensured_vsphere_connection).with(pool_object).and_return(connection)
          expect(subject).to receive(:get_vm_details).and_return(vm_details)
          expect(subject).to receive(:run_select_hosts).with(poolname, {})
          expect(subject).to receive(:vm_in_target?).and_return true
          expect(subject).to receive(:migration_enabled?).and_return true
        end
        vm_object.summary.runtime.host = host_object
      end

      it 'logs a message that no migration is required' do
        expect(logger).to receive(:log).with('s', "[ ] [#{poolname}] No migration required for '#{vmname}' running on #{parent_host}")

        subject.migrate_vm(poolname, vmname)
      end
    end

    context 'with migration limit exceeded' do
      before(:each) do
        subject.connection_pool.with_metrics do |pool_object|
          expect(subject).to receive(:ensured_vsphere_connection).with(pool_object).and_return(connection)
          expect(subject).to receive(:get_vm_details).and_return(vm_details)
          expect(subject).to_not receive(:run_select_hosts)
          expect(subject).to_not receive(:vm_in_target?)
          expect(subject).to receive(:migration_enabled?).and_return true
          redis_connection_pool.with do |redis|
            expect(redis).to receive(:scard).with('vmpooler__migration').and_return(5)
          end
        end
        vm_object.summary.runtime.host = host_object
      end

      it 'should log the current host' do
        expect(logger).to receive(:log).with('s', "[ ] [#{poolname}] '#{vmname}' is running on #{parent_host}. No migration will be evaluated since the migration_limit has been reached")

        subject.migrate_vm(poolname, vmname)
      end
    end

    context 'when an error occurs' do
      before(:each) do
        subject.connection_pool.with_metrics do |pool_object|
          expect(subject).to receive(:ensured_vsphere_connection).with(pool_object).and_return(connection)
          expect(subject).to receive(:get_vm_details).and_return(vm_details)
          expect(subject).to receive(:run_select_hosts)
          expect(subject).to receive(:vm_in_target?).and_return false
          expect(subject).to receive(:migration_enabled?).and_return true
          expect(subject).to receive(:select_next_host).and_raise(RuntimeError,'Mock migration error')
        end
        vm_object.summary.runtime.host = host_object
      end
      it 'should log the current host' do
        expect(logger).to receive(:log).with('s', "[!] [#{poolname}] '#{vmname}' is running on #{parent_host}")

        expect{subject.migrate_vm(poolname, vmname)}.to raise_error(RuntimeError, 'Mock migration error')
      end
    end
  end

  describe '#migrate_vm_to_new_host' do
    let(:parent_host) { 'host1' }
    let(:new_host) { 'host2' }
    let(:datacenter) { 'dc1' }
    let(:cluster) { 'cluster1' }
    let(:architecture) { 'v4' }
    let(:host_object) { mock_RbVmomi_VIM_HostSystem({ :name => parent_host })}
    let(:new_host_object) { mock_RbVmomi_VIM_HostSystem({ :name => new_host })}
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname })}
    let(:config) { YAML.load(<<-EOT
---
:config:
  migration_limit: 5
:pools:
  - name: '#{poolname}'
    datacenter: '#{datacenter}'
    clone_target: '#{cluster}'
EOT
      )
    }
    let(:vm_details) {
      {
        'host_name' => parent_host,
        'object' => vm_object,
        'architecture' => architecture
      }
    }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    it' migrates a vm' do
      expect(subject).to receive(:select_next_host).and_return(new_host)
      expect(subject).to receive(:find_host_by_dnsname).and_return(new_host_object)
      expect(subject).to receive(:migrate_vm_and_record_timing).and_return(format('%.2f', (Time.now - (Time.now - 15))))
      expect(logger).to receive(:log).with('s', "[>] [#{poolname}] '#{vmname}' migrated from host1 to host2 in 15.00 seconds")
      subject.migrate_vm_to_new_host(poolname, vmname, vm_details, connection)
    end
  end

  describe '#create_folder' do
    let(:datacenter) { 'dc1' }
    let(:datacenter_object) { mock_RbVmomi_VIM_Datacenter() }
    let(:folder_object) { mock_RbVmomi_VIM_Folder({ :name => 'pool1'}) }
    let(:new_folder) { poolname }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    it 'creates a folder' do
      expect(connection.serviceInstance).to receive(:find_datacenter).with(datacenter).and_return(datacenter_object)
      expect(datacenter_object.vmFolder).to receive(:traverse).with(new_folder, RbVmomi::VIM::Folder, true).and_return(folder_object)

      result = subject.create_folder(connection, new_folder, datacenter)
      expect(result).to eq(folder_object)
    end

    context 'with folder_object returning nil' do
      it 'shoud raise an error' do
        expect(connection.serviceInstance).to receive(:find_datacenter).with(datacenter).and_return(datacenter_object)
        expect(datacenter_object.vmFolder).to receive(:traverse).with(new_folder, RbVmomi::VIM::Folder, true).and_return(nil)

        expect{subject.create_folder(connection, new_folder, datacenter)}.to raise_error("Cannot create folder #{new_folder}")
      end
    end
  end

  describe '#migration_enabled?' do
    let(:config) {
      { :config => { 'migration_limit' => 5 } }
    }
    it 'returns true if migration is enabled' do
      result = subject.migration_enabled?(config)
      expect(result).to be true
    end

    context 'with migration disabled' do
      let(:config) {
        { :config => { } }
      }
      it 'should return false' do
        result = subject.migration_enabled?(config)
        expect(result).to be false
      end
    end

    context 'with non-integer value for migration limit' do
      let(:config) {
        { :config => { 'migration_limit' => 1.0 } }
      }
      it 'should return false' do
        result = subject.migration_enabled?(config)
        expect(result).to be false
      end
    end
  end

  describe '#find_least_used_hosts' do
    let(:cluster_name) { 'cluster' }
    let(:missing_cluster_name) { 'missing_cluster' }
    let(:datacenter_object) { mock_RbVmomi_VIM_Datacenter() }
    let(:percentage) { 100 }

    before(:each) do
      # This mocking is a little fragile but hard to do without a real vCenter instance
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
      allow(connection.serviceInstance).to receive(:find_datacenter).and_return(datacenter_object)
      datacenter_object.hostFolder.childEntity = [cluster_object]
    end

    context 'missing cluster' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [{
          :name => cluster_name,
      }]})}
      let(:expected_host) { cluster_object.host[0] }
#,datacenter_name
      it 'should raise an error' do
        expect{subject.find_least_used_hosts(missing_cluster_name,datacenter_name,percentage)}.to raise_error(RuntimeError,/Cluster #{missing_cluster_name} cannot be found/)
      end
    end

    context 'standalone host within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [{
          :name => cluster_name,
      }]})}
      let(:expected_host) { cluster_object.host[0][:name] }

      it 'should return the standalone host' do
        result = subject.find_least_used_hosts(cluster_name,datacenter_name,percentage)

        expect(result['hosts'][0]).to be(expected_host)
      end
    end

    context 'standalone host outside the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [{
          :name => cluster_name,
          :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024,
      }]})}
      let(:expected_host) { cluster_object.host[0] }

      it 'should raise an error' do
        expect{subject.find_least_used_hosts(missing_cluster_name,datacenter_name,percentage)}.to raise_error(RuntimeError,/Cluster #{missing_cluster_name} cannot be found/)
      end
    end

    context 'cluster of 3 hosts within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [
          { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1].name }

      it 'should return the standalone host' do
        result = subject.find_least_used_hosts(cluster_name,datacenter_name,percentage)

        expect(result['hosts'][0]).to be(expected_host)
      end
    end

    context 'cluster of 3 hosts all outside of the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [
          { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1] }

      it 'should raise an error' do
        expect{subject.find_least_used_hosts(missing_cluster_name,datacenter_name,percentage)}.to raise_error(RuntimeError,/Cluster #{missing_cluster_name} cannot be found/)
      end
    end

    context 'cluster of 5 hosts of which one is out of limits and one has wrong CPU type' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [
          { :overall_cpu_usage => 31, :overall_memory_usage => 31, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :cpu_model => 'different cpu model', :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1].name }

      it 'should return the standalone host' do
        result = subject.find_least_used_hosts(cluster_name,datacenter_name,percentage)

        expect(result['hosts'][0]).to be(expected_host)
      end
    end

    context 'cluster of 3 hosts all outside of the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({
        :name => cluster_name,
        :hosts => [
          { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
          { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1] }

      it 'should return a host' do
        pending('https://github.com/puppetlabs/vmpooler/issues/206')
        result = subject.find_least_used_hosts(missing_cluster_name,datacenter_name,percentage)
        expect(result).to_not be_nil
      end
    end
  end

  describe '#find_cluster' do
    let(:cluster) {'cluster'}
    let(:host) { 'host' }
    let(:missing_cluster) {'missing_cluster'}

    context 'no clusters in the datacenter' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name }
          ]
        }
      }}

      it 'should return nil if the cluster is not found' do
        expect(subject.find_cluster(missing_cluster,connection,datacenter_name)).to be_nil
      end
    end

    context 'with a single layer folder hierarchy' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name,
              :hostfolder_tree => {
                'cluster1' =>  {:object_type => 'cluster_compute_resource'},
                'cluster2' => {:object_type => 'cluster_compute_resource'},
                cluster => {:object_type => 'cluster_compute_resource'},
                'cluster3' => {:object_type => 'cluster_compute_resource'},
                host => {:object_type => 'compute_resource'},
              }
            }
          ]
        }
      }}

      it 'should return the cluster when found' do
        result = subject.find_cluster(cluster,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(cluster)
      end

      it 'should return the single host when found' do
        result = subject.find_cluster(host,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(host)
      end

      it 'should return nil if the cluster is not found' do
        expect(subject.find_cluster(missing_cluster,connection,datacenter_name)).to be_nil
      end
    end

    context 'with a single layer folder hierarchy with multiple datacenters' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => 'AnotherDC',
              :hostfolder_tree => {
                'cluster1' =>  {:object_type => 'cluster_compute_resource'},
                'cluster2' => {:object_type => 'cluster_compute_resource'},
              }
            },
            { :name => datacenter_name,
              :hostfolder_tree => {
                cluster => {:object_type => 'cluster_compute_resource'},
                'cluster3' => {:object_type => 'cluster_compute_resource'},
                host => {:object_type => 'compute_resource'}
              }
            }
          ]
        }
      }}

      it 'should return the cluster when found' do
        result = subject.find_cluster(cluster,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(cluster)
      end

      it 'should return the single host when found' do
        result = subject.find_cluster(host,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(host)
      end

      it 'should return nil if the cluster is not found' do
        expect(subject.find_cluster(missing_cluster,connection,'AnotherDC')).to be_nil
      end
    end

    context 'with a multi layer folder hierarchy' do
      let(:connection_options) {{
        :serviceContent => {
          :datacenters => [
            { :name => datacenter_name,
              :hostfolder_tree => {
                'cluster1' =>  {:object_type => 'cluster_compute_resource'},
                'folder2' => {
                  :children => {
                    cluster => {:object_type => 'cluster_compute_resource'},
                  }
                },
                'cluster3' => {:object_type => 'cluster_compute_resource'},
                'folder4' => {
                  :children => {
                    host => {:object_type => 'compute_resource'},
                  }
                }
              }
            }
          ]
        }
      }}

      it 'should return the cluster when found' do
        result = subject.find_cluster(cluster,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(cluster)
      end

      it 'should return the host when found' do
        result = subject.find_cluster(host,connection,datacenter_name)

        expect(result).to_not be_nil
        expect(result.name).to eq(host)
      end

      it 'should return nil if the cluster is not found' do
        expect(subject.find_cluster(missing_cluster,connection,datacenter_name)).to be_nil
      end
    end
  end

  describe '#get_cluster_host_utilization' do
    context 'standalone host within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [{}]}) }
      
      it 'should return array with one element' do
        result = subject.get_cluster_host_utilization(cluster_object)
        expect(result).to_not be_nil
        expect(result.count).to eq(1)
      end
    end

    context 'standalone host which is out the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      
      it 'should return array with 0 elements' do
        result = subject.get_cluster_host_utilization(cluster_object)
        expect(result).to_not be_nil
        expect(result.count).to eq(0)
      end
    end

    context 'cluster with 3 hosts within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      
      it 'should return array with 3 elements' do
        result = subject.get_cluster_host_utilization(cluster_object)
        expect(result).to_not be_nil
        expect(result.count).to eq(3)
      end
    end

    context 'cluster with 5 hosts of which 3 within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      
      it 'should return array with 3 elements' do
        result = subject.get_cluster_host_utilization(cluster_object)
        expect(result).to_not be_nil
        expect(result.count).to eq(3)
      end
    end

    context 'cluster with 3 hosts of which none are within the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      
      it 'should return array with 0 elements' do
        result = subject.get_cluster_host_utilization(cluster_object)
        expect(result).to_not be_nil
        expect(result.count).to eq(0)
      end
    end
  end

  describe '#find_least_used_vpshere_compatible_host' do
    let(:vm) { mock_RbVmomi_VIM_VirtualMachine() }

    context 'standalone host within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [{}]}) }
      let(:standalone_host) { cluster_object.host[0] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = standalone_host
      end

      it 'should return the standalone host' do
        result = subject.find_least_used_vpshere_compatible_host(vm)

        expect(result).to_not be_nil
        expect(result[0]).to be(standalone_host)
        expect(result[1]).to eq(standalone_host.name)
      end
    end

    context 'standalone host outside of limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:standalone_host) { cluster_object.host[0] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = standalone_host
      end

      it 'should raise error' do
        expect{subject.find_least_used_vpshere_compatible_host(vm)}.to raise_error(/There is no host candidate in vcenter that meets all the required conditions/)
      end
    end

    context 'cluster of 3 hosts within limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = expected_host
      end

      it 'should return the least used host' do
        result = subject.find_least_used_vpshere_compatible_host(vm)

        expect(result).to_not be_nil
        expect(result[0]).to be(expected_host)
        expect(result[1]).to eq(expected_host.name)
      end
    end

    context 'cluster of 3 hosts all outside of the limits' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = expected_host
      end

      it 'should raise error' do
        expect{subject.find_least_used_vpshere_compatible_host(vm)}.to raise_error(/There is no host candidate in vcenter that meets all the required conditions/)
      end
    end

    context 'cluster of 5 hosts of which one is out of limits and one has wrong CPU type' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 31, :overall_memory_usage => 31, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :cpu_model => 'different cpu model', :overall_cpu_usage => 1, :overall_memory_usage => 1, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 11, :overall_memory_usage => 11, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 100, :overall_memory_usage => 100, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 21, :overall_memory_usage => 21, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[2] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = expected_host
      end

      it 'should return the least used host' do
        result = subject.find_least_used_vpshere_compatible_host(vm)

        expect(result).to_not be_nil
        expect(result[0]).to be(expected_host)
        expect(result[1]).to eq(expected_host.name)
      end
    end

    context 'cluster of 3 hosts all with the same utilisation' do
      let(:cluster_object) { mock_RbVmomi_VIM_ComputeResource({:hosts => [
        { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
        { :overall_cpu_usage => 10, :overall_memory_usage => 10, :cpu_speed => 100, :num_cores_per_cpu => 1, :num_cpu => 1, :memory_size => 100.0 * 1024 * 1024 },
      ]}) }
      let(:expected_host) { cluster_object.host[1] }

      before(:each) do
        # This mocking is a little fragile but hard to do without a real vCenter instance
        vm.summary.runtime.host = expected_host
      end

      it 'should return a host' do
        pending('https://github.com/puppetlabs/vmpooler/issues/206 is fixed')
        result = subject.find_least_used_vpshere_compatible_host(vm)

        expect(result).to_not be_nil
      end
    end
  end

  describe '#find_snapshot' do
    let(:snapshot_name) {'snapshot'}
    let(:missing_snapshot_name) {'missing_snapshot'}
    let(:vm) { mock_RbVmomi_VIM_VirtualMachine(mock_options) }
    let(:snapshot_object) { mock_RbVmomi_VIM_VirtualMachineSnapshot() }

    context 'VM with no snapshots' do
      let(:mock_options) {{ :snapshot_tree => nil }}
      it 'should return nil' do
        expect(subject.find_snapshot(vm,snapshot_name)).to be_nil
      end
    end

    context 'VM with a single layer of snapshots' do
      let(:mock_options) {{
        :snapshot_tree => {
          'snapshot1' => nil,
          'snapshot2' => nil,
          'snapshot3'  => nil,
          'snapshot4' => nil,
          snapshot_name => { :ref => snapshot_object},
        }
      }}

      it 'should return snapshot which matches the name' do
        result = subject.find_snapshot(vm,snapshot_name)
        expect(result).to be(snapshot_object)
      end

      it 'should return nil which no matches are found' do
        result = subject.find_snapshot(vm,missing_snapshot_name)
        expect(result).to be_nil
      end
    end

    context 'VM with a nested layers of snapshots' do
      let(:mock_options) {{
        :snapshot_tree => {
          'snapshot1' => nil,
          'snapshot2' => nil,
          'snapshot3'  => { :children => {
            'snapshot4' => nil,
            'snapshot5' => { :children => {
              snapshot_name => { :ref => snapshot_object},
            }},
          }},
          'snapshot6' => nil,
        }
      }}

      it 'should return snapshot which matches the name' do
        result = subject.find_snapshot(vm,snapshot_name)
        expect(result).to be(snapshot_object)
      end

      it 'should return nil which no matches are found' do
        result = subject.find_snapshot(vm,missing_snapshot_name)
        expect(result).to be_nil
      end
    end
  end

  describe '#find_vm' do
    let(:missing_vm) { 'missing_vm' }
    let(:folder) { 'Pooler/pool1' }
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine() }

    before(:each) do
      allow(connection.searchIndex).to receive(:FindByInventoryPath)
    end

    it 'should call FindByInventoryPath with the correct parameters' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath)

      subject.find_vm(poolname,vmname,connection)
    end

    it 'should return the VM object when found' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_return(vm_object)

      expect(subject.find_vm(poolname,vmname,connection)).to be(vm_object)
    end

    it 'should return nil if the VM is not found' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)

      expect(subject.find_vm(poolname,missing_vm,connection)).to be_nil
    end
  end

  describe '#get_base_vm_container_from' do
    it 'should return a recursive view of type VirtualMachine' do
      result = subject.get_base_vm_container_from(connection)

      expect(result.recursive).to be true
      expect(result.type).to eq(['VirtualMachine'])
    end
  end

  describe '#get_snapshot_list' do
    let(:snapshot_name) {'snapshot'}
    let(:snapshot_tree) { mock_RbVmomi_VIM_VirtualMachine(mock_options).snapshot.rootSnapshotList }
    let(:snapshot_object) { mock_RbVmomi_VIM_VirtualMachine() }

    it 'should raise if the snapshot tree is nil' do
      expect{ subject.get_snapshot_list(nil,snapshot_name)}.to raise_error(NoMethodError)
    end

    context 'VM with a single layer of snapshots' do
      let(:mock_options) {{
        :snapshot_tree => {
          'snapshot1' => nil,
          'snapshot2' => nil,
          'snapshot3'  => nil,
          'snapshot4' => nil,
          snapshot_name => { :ref => snapshot_object},
        }
      }}

      it 'should return snapshot which matches the name' do
        result = subject.get_snapshot_list(snapshot_tree,snapshot_name)
        expect(result).to be(snapshot_object)
      end
    end

    context 'VM with a nested layers of snapshots' do
      let(:mock_options) {{
        :snapshot_tree => {
          'snapshot1' => nil,
          'snapshot2' => nil,
          'snapshot3'  => { :children => {
            'snapshot4' => nil,
            'snapshot5' => { :children => {
              snapshot_name => { :ref => snapshot_object},
            }},
          }},
          'snapshot6' => nil,
        }
      }}

      it 'should return snapshot which matches the name' do
        result = subject.get_snapshot_list(snapshot_tree,snapshot_name)
        expect(result).to be(snapshot_object)
      end
    end
  end

  describe '#migrate_vm_host' do
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine({ :name => vmname })}
    let(:host_object) { mock_RbVmomi_VIM_HostSystem({ :name => 'HOST' })}
    let(:relocate_task) { mock_RbVmomi_VIM_Task() }

    before(:each) do
      allow(vm_object).to receive(:RelocateVM_Task).and_return(relocate_task)
      allow(relocate_task).to receive(:wait_for_completion)
    end

    it 'should call RelocateVM_Task' do
      expect(vm_object).to receive(:RelocateVM_Task).and_return(relocate_task)

      subject.migrate_vm_host(vm_object,host_object)
    end

    it 'should use a Relocation Spec object with correct host' do
      expect(vm_object).to receive(:RelocateVM_Task).with(relocation_spec_with_host(host_object))

      subject.migrate_vm_host(vm_object,host_object)
    end

    it 'should wait for the relocation to complete' do
      expect(relocate_task).to receive(:wait_for_completion)

      subject.migrate_vm_host(vm_object,host_object)
    end

    it 'should return the result of the relocation' do
      expect(relocate_task).to receive(:wait_for_completion).and_return('RELOCATE_RESULT')

      expect(subject.migrate_vm_host(vm_object,host_object)).to eq('RELOCATE_RESULT')
    end
  end

  describe 'find_template_vm' do
    let(:vm_object) { mock_RbVmomi_VIM_VirtualMachine() }

    before(:each) do
      allow(connection.searchIndex).to receive(:FindByInventoryPath)
    end
    it 'should raise an error when the datacenter cannot be found' do
      config[:providers][:vsphere]['datacenter'] = nil

      expect{ subject.find_template_vm(config[:pools][0],connection) }.to raise_error('cannot find datacenter')
    end

    it 'should raise an error when the template specified cannot be found' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_return(nil)

      expect{ subject.find_template_vm(config[:pools][0],connection) }.to raise_error("Pool #{poolname} specifies a template VM of #{config[:pools][0]['template']} which does not exist for the provider vsphere")
    end

    it 'should return the vm object' do
      expect(connection.searchIndex).to receive(:FindByInventoryPath).and_return(vm_object)

      subject.find_template_vm(config[:pools][0],connection)
    end
  end

  describe 'valid_template_path?' do

    it 'should return true with a valid template path' do
      expect(subject.valid_template_path?('test/template')).to eq(true)
    end

    it 'should return false when no / is found' do
      expect(subject.valid_template_path?('testtemplate')).to eq(false)
    end

    it 'should return false when template path begins with /' do
      expect(subject.valid_template_path?('/testtemplate')).to eq(false)
    end

    it 'should return false when template path ends with /' do
      expect(subject.valid_template_path?('testtemplate/')).to eq(false)
    end
  end

  describe 'create_template_delta_disks' do
    let(:template_object) { mock_RbVmomi_VIM_VirtualMachine({
        :name => vmname,
      })
    }

    before(:each) do
      allow(subject).to receive(:connect_to_vsphere).and_return(connection)
    end

    context 'with a template VM found' do

      before(:each) do
        expect(subject).to receive(:find_template_vm).and_return(template_object)
      end

      it 'should reconfigure the VM creating delta disks' do
        expect(template_object).to receive(:add_delta_disk_layer_on_all_disks)

        subject.create_template_delta_disks(config[:pools][0])
      end
    end
  end

  describe 'get_disk_backing' do

    it 'should return moveChildMostDiskBacking when linked clone enabled' do
      expect( subject.get_disk_backing({'create_linked_clone' => true}) ).to eq(:moveChildMostDiskBacking)
    end

    it 'should return moveAllDiskBackingsAndConsolidate when no preference is specified' do
      expect( subject.get_disk_backing({})).to eq(:moveAllDiskBackingsAndConsolidate)
    end

    it 'should return moveAllDiskBackingsAndConsolidate when linked clone is false' do
      expect( subject.get_disk_backing({create_linked_clone: false})).to eq(:moveAllDiskBackingsAndConsolidate)
    end
  end

  describe 'linked_clone?' do
    it 'should return true when linked clone is enabled on the pool' do
      expect( subject.linked_clone?({'create_linked_clone' => true}) ).to be true
    end

    it 'should return nil when linked clone is not enabled on the pool' do
      expect( subject.linked_clone?({}) ).to be nil
    end
  end
end