Meta variables in controllers

ApplicationControllerBase mixins includes a set_meta_variables method.

def set_meta_variables(instance, mappings = {})
  m = {
    title: :title,
    image: :cover,
    description: :perex,
    meta_title: :meta_title,
    meta_description: :meta_description,
  }.merge(mappings)
  ...
end

It's used in PagesControllerBase mixin

set_meta_variables(@page)

It tries to set view values for title and og: attributes from the passed instance given the mappings (defaults are shown above). Fails silently.

Both meta_title and meta_description have precedence over title and description, respectively.

Example

Say we have a product with a name and description and no meta field, the target image is taken from a has_one :main_image.

# app/controllers/my_project/products_controller.rb

class MyProject::ProductsController < ApplicationController
  def show
    @product = MyProject::Product.find(params[:id])
    set_meta_variables(@product, title: :name,
                                 description: :description,
                                 image: :main_image)
  end
end