Ruby / Roda - Web Framework / Plugins / :view_options

Introduction

The :view_options plugin allows you to override view and layout options and locals for specific branches and routes.

plugin :render
  plugin :view_options

  route do |r|
    r.on "users" do
      set_layout_options :template=>'users_layout'
      set_layout_locals :title=>'Users'
      set_view_options :engine=>'haml'
      set_view_locals :footer=>'(c) Roda'

      # ...
    end
  end

The options and locals you specify have higher precedence than the :render plugin options, but lower precedence than options you directly pass to the view/render methods.

View Subdirectories

The :view_options plugin also has special support for sites that have outgrown a flat view directory and use subdirectories for views.

It allows you to set the view directory to use, and template names that do NOT contain a slash will automatically use that view subdirectory.

Example:

plugin :render, :layout=>'./layout'
  plugin :view_options

  route do |r|
    r.on "users" do
      set_view_subdir 'users'
      
      r.get :id do
        append_view_subdir 'profile'
        view 'index' # uses ./views/users/profile/index.erb
      end

      r.get 'list' do
        view 'lists/users' # uses ./views/lists/users.erb
      end
    end
  end

Note! When a view subdirectory is set, the layout will also be looked up in the subdirectory unless it contains a slash.

So if you want to use a view subdirectory for templates but have a shared layout, you should make sure your layout contains a slash, similar to the example above.

Per-branch HTML escaping

If you have an existing Roda application that doesn't use automatic HTML escaping for <%= %> tags via the :render plugin's :escape option, but you want to switch to using the :escape option, you can now do so without making all changes at once.

With #.set_view_options, you can now specify escaping or not on a per branch basis in the routing tree:

plugin :render, escape: true
  plugin :view_options
  
  route do |r|
  
    # Don't escape <%= %> by default
    set_view_options :template_opts=>{:engine_class=>nil}

    r.on "users" do
      
      # Escape <%= %> in this branch
      set_view_options :template_opts=>{:engine_class=>render_opts[:template_opts][:engine_class]}
      
    end
    
  end

InstanceMethods

The following methods are created via metaprogramming:

Method Name:	Description:
set_layout_locals	Set locals to use in the layout
set_layout_options	Set options to use when rendering the layout
set_view_locals	Set locals to use in the view
set_view_options	Set options to use when rendering the view

`#.append_view_subdir(v)`

Append a view subdirectory to use. If there hasn't already been a view subdirectory set, this just sets it to the argument. If there has already been a view subdirectory set, this sets the view subdirectory to a subdirectory of the existing view subdirectory.

`#.set_view_subdir(v)`

Set the view subdirectory to use. This can be set to nil to not use a view subdirectory.