func TestUpdateOne(t *testing.T) {
	db := NewInMemDatabase()

	instance := new(types.VirtualMachine)
	instance.SetUuid(uuid.New())
	instance.SetName("instance")
	assert.NoError(t, db.Put(instance, nil, UIDList{}))

	vmi1 := new(types.VirtualMachineInterface)
	vmi1.SetUuid(uuid.New())
	vmi1.SetName("port1")
	assert.NoError(t, db.Put(vmi1, nil, GetReferenceList(vmi1)))

	vmi1.AddVirtualMachine(instance)
	assert.NoError(t, db.Update(vmi1, GetReferenceList(vmi1)))

	result, err := db.GetBackReferences(parseUID(instance.GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Contains(t, result, parseUID(vmi1.GetUuid()))

	vmi1.ClearVirtualMachine()
	assert.NoError(t, db.Update(vmi1, GetReferenceList(vmi1)))
	result, err = db.GetBackReferences(parseUID(instance.GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, result, 0)
}
func (m *InstanceManager) LocateInstance(tenant, podName, uid string) *types.VirtualMachine {
	obj, err := m.client.FindByUuid("virtual-machine", string(uid))
	if err == nil {
		return obj.(*types.VirtualMachine)
	}

	instance := new(types.VirtualMachine)
	instance.SetName(podName)
	instance.SetUuid(uid)
	err = m.client.Create(instance)
	if err != nil {
		glog.Errorf("Create %s: %v", podName, err)
		return nil
	}
	return instance
}
func TestUpdateRefs(t *testing.T) {
	db := NewInMemDatabase()

	var instances [8]*types.VirtualMachine
	for i := 0; i < 8; i++ {
		instance := new(types.VirtualMachine)
		instance.SetUuid(uuid.New())
		instance.SetName(fmt.Sprintf("instance-%d", i))
		assert.NoError(t, db.Put(instance, nil, UIDList{}))
		instances[i] = instance
	}

	vmi1 := new(types.VirtualMachineInterface)
	vmi1.SetUuid(uuid.New())
	vmi1.SetName("port1")
	vmi1.AddVirtualMachine(instances[0])
	vmi1.AddVirtualMachine(instances[1])
	vmi1.AddVirtualMachine(instances[2])
	assert.NoError(t, db.Put(vmi1, nil, GetReferenceList(vmi1)))

	vmi2 := new(types.VirtualMachineInterface)
	vmi2.SetUuid(uuid.New())
	vmi2.SetName("port2")
	vmi2.AddVirtualMachine(instances[2])
	vmi2.AddVirtualMachine(instances[4])
	vmi2.AddVirtualMachine(instances[3])
	assert.NoError(t, db.Put(vmi2, nil, GetReferenceList(vmi2)))

	r2, err := db.GetBackReferences(parseUID(instances[2].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r2, 2)
	assert.Contains(t, r2, parseUID(vmi1.GetUuid()))
	assert.Contains(t, r2, parseUID(vmi2.GetUuid()))

	r3, err := db.GetBackReferences(parseUID(instances[3].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r3, 1)

	vmi2.ClearVirtualMachine()
	vmi2.AddVirtualMachine(instances[4])
	vmi2.AddVirtualMachine(instances[6])
	assert.NoError(t, db.Update(vmi2, GetReferenceList(vmi2)))

	r2, err = db.GetBackReferences(parseUID(instances[2].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r2, 1)
	assert.Contains(t, r2, parseUID(vmi1.GetUuid()))

	r3, err = db.GetBackReferences(parseUID(instances[3].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r3, 0)

	r4, err := db.GetBackReferences(parseUID(instances[4].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r4, 1)
	assert.Contains(t, r4, parseUID(vmi2.GetUuid()))

	vmi1.ClearVirtualMachine()
	vmi1.AddVirtualMachine(instances[0])
	vmi1.AddVirtualMachine(instances[1])
	vmi1.AddVirtualMachine(instances[5])
	vmi1.AddVirtualMachine(instances[4])
	assert.NoError(t, db.Update(vmi1, GetReferenceList(vmi1)))

	r4, err = db.GetBackReferences(parseUID(instances[4].GetUuid()), "virtual_machine_interface")
	assert.NoError(t, err)
	assert.Len(t, r4, 2)
	assert.Contains(t, r4, parseUID(vmi1.GetUuid()))
	assert.Contains(t, r4, parseUID(vmi2.GetUuid()))
}