Question

I have a very simple Project form with a name field and a select box with various Client names in it:

<%= f.label :name %><br/>
<%= f.text_field :name %>

<%= f.label :client_id %><br/>
<% options = current_user.clients.all.map { |client| [client.name, client.id] } %>
<%= f.select(:client_id, options, {:prompt => 'Select...'}) %>

Now when a user hits submit without actually selecting a Client from the select box, an error is returned saying that a Client with ID ” ” cannot be found.

Is there any way to change my controller code so that it works?

def create
  client = current_user.clients.find(params[:project][:client_id])
  @project = client.projects.build(params[:project])
  if @project.save
    flash[:success] = "Project created."
    redirect_to @project
  else
    render :action => "new"
  end
end

It’s the local client variable that causes the trouble but I don’t know how to fix it so that errors will be handled by the validation methods.

Answer 1

Above code is trying to fetch a client object by passing id as nil. Following code should work, provided there is a validation for client record before saving project record.

def create
  client = current_user.clients.find(params[:project][:client_id]) rescue nil
  unless client
    @project = Project.new(params[:project]) # Required for making the form fields pre-populated
    @project.valid? # this line will populate the error messages
    render :action => "new"
    return
  end

  @project = client.projects.build(params[:project])
  if @project.save
    flash[:success] = "Project created."
    redirect_to @project
  else
    render :action => "new"
  end
end