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Set up a new Rails application

Bootstrapping a new application

To create a rails app, run the following (skip uncommon stuff).

rails new myapp --skip-javascript --skip-test --skip-bundle --skip-spring --skip-action-cable --skip-action-mailer --skip-active-storage

Replace the Gemfile with the gems you need. Here is an example.

ruby File.read(".ruby-version").strip

source "https://rubygems.org"

gem "rails", "~> 5.2"

gem "bootsnap", "~> 1"
gem "gds-api-adapters", "~> 52"
gem "gds-sso", "~> 13"
gem "govuk_app_config", "~> 1"
gem "govuk_publishing_components", "~> 9.5"
gem "pg", "~> 1"
gem "plek", "~> 2"
gem "uglifier", "~> 4"

group :development do
  gem "listen", "~> 3"
end

group :test do
  gem "simplecov", "~> 0.16"
end

group :development, :test do
  gem "byebug", "~> 10"
  gem "govuk-lint", "~> 3"
  gem "rspec-rails", "~> 3"
end

Run bundle && rails g rspec:install and replace spec/*helper.rb.

## spec/rails_helper.rb
rm spec/rails_helper.rb

## spec/spec_helper.rb
require "byebug"
require "simplecov"

ENV["RAILS_ENV"] ||= "test"
require File.expand_path("../../config/environment", __FILE__)
require "rspec/rails"

Dir[Rails.root.join("spec/support/**/*.rb")].each { |f| require f }
SimpleCov.start

RSpec.configure do |config|
  config.expose_dsl_globally = false
  config.infer_spec_type_from_file_location!
  config.use_transactional_fixtures = true
end

In config, replace the content of database.yml with the following.

default: &default
  adapter: postgresql
  encoding: unicode
  pool: 12
  template: template0

development:
  <<: *default
  database: myapp_development
  url: <%= ENV["DATABASE_URL"]%>

test:
  <<: *default
  database: myapp_test
  url: <%= ENV["TEST_DATABASE_URL"] %>

production:
  <<: *default
  database: myapp_production
  url: <%= ENV["DATABASE_URL"]%>

In config, replace credentials.yml.env and master.key with secrets.yml.

development:
  secret_key_base: secret

test:
  secret_key_base: secret

production:
  secret_key_base: <%= ENV['SECRET_KEY_BASE'] %>

In config, replace the content of routes.rb with the following healthcheck.

Rails.application.routes.draw do
  get "/healthcheck", to: proc { [200, {}, ["OK"]] }
end

Now is a good time to run bin/setup. Lastly, create lib/tasks/lint.rake with this.

desc "Run govuk-lint on all files"
task "lint" do
  sh "govuk-lint-ruby --format clang"
  sh "govuk-lint-sass app/assets/stylesheets"
end

Then add task default: %i(spec lint) in Rakefile and finally run rake.

Puppet, DNS, Sentry and beyond

Configuring the app for Jenkins

Create a Jenkinsfile in your repo with the following content.

#!/usr/bin/env groovy

library("govuk")

node {
  govuk.buildProject(
    brakeman: true
  )
}

You also need to add a Jenkins integration to the repo on Github:

  1. In GitHub, go to Settings -> Integrations & Services
  2. Add Jenkins (GitHub plugin)
  3. Add the link to the CI GitHub webhook
  4. Make sure Active is ticked

Finally, add your app to the list of deployable applications in govuk-puppet.

More in the Applications section

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This page was last reviewed on 1 February 2019. It needs to be reviewed again on 1 August 2019 by the page owner #govuk-2ndline .
This page was set to be reviewed before 1 August 2019 by the page owner #govuk-2ndline. This might mean the content is out of date.