Set up a new Rails application
Familiarise yourself with the conventions
We have documented conventions for Rails applications and conventions for naming applications in GOV.UK.
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 "rspec-rails", "~> 3"
gem "rubocop-govuk"
gem "scss-lint-govuk"
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 "Lint files"
task "lint" do
sh "rubocop --format clang"
sh "scss-lint app/assets/stylesheets"
end
Then add task default: %i(spec lint) in Rakefile and finally run rake.
Puppet, DNS, Sentry and beyond
- To prepare the servers for your app, follow the doc in govuk-puppet
- To configure app deployments, follow the docs in govuk-app-deployment
- To enable external DNS, follow the article in the Developer Docs
- Make a PR to add your app to data/applications.yml for these docs
- Then ask 2nd line to run the task in govuk-saas-config to update Sentry
- Add the application to the Release app (the create button is at the bottom)
- Add the application to the Deploy_App job in Jenkins (click Configure)
- Run the Deploy_App job using with
with_migrationsoption to get started
Configuring the app for Jenkins
Create a Jenkinsfile in your repo with the following content.
#!/usr/bin/env groovy
library("govuk")
node {
govuk.buildProject()
}
You also need to add a Jenkins integration to the repo on GitHub:
- In GitHub, go to Settings -> Integrations & Services
- Add Jenkins (GitHub plugin)
- Add the link to the CI GitHub webhook
- Make sure Active is ticked
Finally, add your app to the list of deployable applications in govuk-puppet.