in cloudstack_loadbalancer.go [570:592]
func symmetricDifference(hostIDs []string, lbInstances []*cloudstack.VirtualMachine) ([]string, []string) {
new := make(map[string]bool)
for _, hostID := range hostIDs {
new[hostID] = true
}
var remove []string
for _, instance := range lbInstances {
if new[instance.Id] {
delete(new, instance.Id)
continue
}
remove = append(remove, instance.Id)
}
var assign []string
for hostID := range new {
assign = append(assign, hostID)
}
return assign, remove
}