Sources procs + class support

[eelcoj]

This extends the sources/programmatic content feature.

First off lamda filtering for sources, like so:

class Content::Product
  sources, :countries, products: -> (products) { products.select(&:featured?) }
end

Then support for class for sources, for which pulling data from external APIs is the most obvious use case. This has been on my list since I first launched Perron. 😊

Initially I thought of adding first-party support for API handling. But instead I opted for a more maintainable and flexible option of simply support adding a class to the sources feature. This is as simple as it is elegant (at least I think it is).

Syntax looks like this:

class Content::Product
  sources repos: { class: GitHubRepo, primary_key: :name }
end

A complete example implementation that pulls GitHub repositories data could look like this (using the Active Resource gem):

class GitHubRepo < ActiveResource::Base
  self.site = "https://api.github.com/"

  def self.all
    find(:all, from: "/users/Rails-Designer/repos", params: { per_page: 5 })
  end
end

Then the typical template setup:

class Content::Project < Perron::Resource
  sources repos: { class: GitHubRepo, primary_key: :name }

  def self.source_template(source)
    <<~TEMPLATE
    ---
    title: #{source.repos.name}
    description: #{source.repos.description}
    language: #{source.repos.language}
    stars: #{source.repos.stargazers_count}
    ---

    #{source.repos.description}
    TEMPLATE
  end
end

Above would pull the repo data and create (and update if changes) erb files into app/content/projects just like it does with local files. ✨