Parklife ♥︎ Rails

A Rails app is a Rack app and as such things Just Work™ but Parklife’s Rails integration includes a few enhancements to make life easier and provides ActiveStorage integration so you can continue using the knowledge and tools you already have.

Getting started

First add Parklife’s Rails integration to your app:

gem 'parklife-rails'

Then run parklife init --rails to generate a Parkfile and bin/static-build tailored for a Rails app. Inside the Parkfile you’ll see the following:

# Load your application, this activates the Parklife/Rails integration and gives
# you access to route helpers and models in this file.
require_relative 'config/environment'

Now you should tell Parklife which paths to include:

Parklife.application.routes do
  # Start from the homepage and crawl all links.
  root crawl: true

  # Some extra paths that aren't discovered by crawling links.
  get feed_path(format: :atom)
  get sitemap_path(format: :xml)

  # A couple more hidden pages.
  get easter_egg_path, crawl: true
end

Listing the routes included in the above Parklife application with parklife routes would output the following:

$ bundle exec parklife routes
/             crawl=true
/feed.atom
/sitemap.xml
/easter_egg   crawl=true
/404.html

Now you can run parklife build which will fetch all the routes and save them to the build directory ready to be served as a static site. Inspecting the build directory might look like this:

$ find build -type f
build/404.html
build/about/index.html
build/blog/2019/03/07/developers-developers-developers/index.html
build/blog/2019/04/21/modern-life-is-rubbish/index.html
build/blog/2019/05/15/introducing-parklife/index.html
build/blog/index.html
build/easter_egg/index.html
build/easter_egg/surprise/index.html
build/feed.atom
build/index.html
build/location/index.html
build/sitemap.xml

Parklife doesn’t know about assets (images, CSS, etc) so you likely also need to generate those and copy them to the build directory, see the example app’s full build script for how you might do this.

ActiveStorage integration

Parklife’s ActiveStorage integration allows you to use ActiveStorage as normal in development, then during a Parklife build any encountered attachments are collected and copied to the build directory so they can be served alongside the rest of your static files. This is achieved via a Rails Engine and custom ActiveStorage DiskService which work together to tweak ActiveStorage URLs so they’re suitable for a static web server.

The integration is opt-in and must first be enabled in config/application.rb (this must be done before the app boots so can’t be in an initializer):

require 'parklife-rails/activestorage'

Then switch to Parklife’s ActiveStorage service in config/storage.yml:

local:
  service: Parklife
  root: <%= Rails.root.join("storage") %>

Finally, use ActiveStorage (almost entirely) as usual:

# Pass a blob/attachment/preview/variant directly to helpers as usual:
image_tag(blog_post.hero_image.variant(:medium))
# => <img src="/parklife/blobs/6adews39uehd44spynetigykwssh/cute-cat.jpg" />
video_tag(product.intro_video)
# => <video src="/parklife/blobs/x74tu8izjv141l8503gwkkruokca/cat-mug.mp4"></video>

# Ask a variant for its path:
blog_post.hero_image.variant(:medium).processed.url
# => "/parklife/blobs/6adews39uehd44spynetigykwssh/cute-cat.jpg"

# Use the route helper:
Rails.application.routes.url_helpers.parklife_blob_path(
  blog_post.hero_image.variant(:medium)
)
# => "/parklife/blobs/6adews39uehd44spynetigykwssh/cute-cat.jpg"

The only quirk is if you want to generate the full URL (including hostname etc), in that case parklife_blob_url doesn’t behave as you’d expect and you must also pass only_path: false:

Rails.application.routes.url_helpers.parklife_blob_url(
  blog_post.hero_image.variant(:medium),
  only_path: false,
)
# => "http://example.com/parklife/blobs/6adews39uehd44spynetigykwssh/cute-cat.jpg"

Now running the standard parklife build will include any encountered attachments in the build directory.