## controller:

  def create
    @service = Service.new(params[:service])
    @notigroups = Notificationgroupdetail.find(:all)
    @notigroups << ["None", "0"]
    @hosts = Host.find(:all).collect {|p| [p.name, p.id] }
    @hosts << ["None", "0"]
    if @service.save
      flash[:notice] = "Service has been added!"
      redirect_to :action => "index"
    else
      flash[:error] = "Could not add service. Check error messages."
      render :action => "new"
    end
  end

## view:
<div id="service-new">
  <% form_for :service, :url => { :action => "create" } do |f| %>
    <fieldset>
      <legend>Main</legend>
      <dl>
        <dt>Name</dt>
        <dd><%= f.text_field :name %> <%= error_message_on(:service, :name) %></dd>
        <dt>Host</dt>
        <dd><%= f.text_field :host %> <%= error_message_on(:service, :host) %></dd>
        <dt>Port</dt>
        <dd><%= f.text_field :port %> <%= error_message_on(:service, :port) %></dd>
        <dt>Protocol check</dt>
        <dd><%= f.select :type, getServiceTypes.sort %> <%= error_message_on(:service, :type) %></dd>
        <dt>Timeout (seconds)</dt>
        <dd><%= f.text_field :timeout, :value => "5" %> <%= error_message_on(:service, :timeout) %></dd>
        <dt>Max. response time (ms)</dt>
        <dd><%= f.text_field :maxres, :value => "250" %> <%= error_message_on(:service, :maxres) %></dd>
        <dt>Notification group</dt>
        <dd>
          <%= f.select :warninggroup, @notigroups %>
          <%= error_message_on(:service, :warninggroup) %>
        </dd>
        <dt>Link to host</dt>
        <dd>
          <%= f.select :linkedhost, @hosts %>
          <%= error_message_on(:service, :linkedhost) %>
        </dd>
      </dl>
    </fieldset>

    <fieldset>
      <legend>Control</legend>
      <%= submit_tag %>
    </fieldset>
  <% end %>
</div>

## model/validation
class Service < ActiveRecord::Base
  validates_presence_of :name
  validates_presence_of :host
  validates_presence_of :type
  validates_presence_of :port
  validates_presence_of :maxres
  validates_presence_of :timeout
  validates_presence_of :warninggroup

  validates_numericality_of :port
  validates_numericality_of :maxres
  validates_numericality_of :timeout
  validates_numericality_of :warninggroup
end

## html output of the field that is complained about:

				<dd><div class="fieldWithErrors"><select id="service_type" name="service[type]"><option value="ftp">FTP</option>
<option value="http">HTTP</option>
<option value="imap">IMAP</option>
<option value="none">None</option>
<option value="pop3">POP3</option>
<option value="smtp">SMTP</option>
<option value="ssh">SSH</option></select></div> <div class="formError">can't be blank</div></dd>

## params[:service]
name: somename
port: 80
timeout: 5
linkedhost: 0
warninggroup: 0
type: ftp
maxres: 250
host: somehost