My own cra-rails template. (It requires permission for a private repository)

cra-rails-template.rb

require 'json'

def run!
  source_dirname = 'create-react-app-with-rails-boilerplate'
  client_app_dir = 'client'

  git clone: 'https://github.com/yhk1038/create-react-app-with-rails-boilerplate.git'

  add_gems
  add_gitignore
  update_package_json client_dir: client_app_dir

  run "cp -r ./#{source_dirname}/client ./#{client_app_dir}"
  update_client_package_name client_dir: client_app_dir
  run "rm -rf ./#{source_dirname}"

  run 'bundle install'
  run 'yarn install'
  run 'yarn client:install'
end

#######################

def add_gems
  gem 'awesome_print'
  gem 'dotenv-rails'
end

def add_gitignore
  File.open('./.gitignore', 'a') do |f|
    f.write <<~CODE
      yarn.lock

      # Client APP Build Result is run on each production server.
      /public/static
      /public/asset-manifest.json
      /public/manifest.json
      /public/index.html
    CODE
  end
end

# Abstract PackageJson Handler
#
class PackageJson
  def initialize(filepath)
    @filepath = filepath
  end

  def read
    file = File.read(@filepath)
    JSON.parse(file, symbolize_names: true)
  end

  def write(hash)
    File.write(@filepath, "#{JSON.pretty_generate(hash)}\n")
  end

  def merge!(hash)
    data = read
    data.merge!(hash)
    write data
  end

  def append
    write yield(read)
  end

  def insert(*before_keys)
    append do |hash|
      cached_map = before_keys.map do |key|
        val = hash[key].dup
        hash.delete key
        [key, val]
      end

      yield(hash)

      cached_map.each { |key, val| hash[key] = val }

      hash
    end
  end
end

def update_package_json(client_dir: 'client')
  package_json = PackageJson.new('./package.json')
  package_json.insert(:dependencies, :devDependencies) do |hash|
    hash[:scripts] ||= {}
    hash[:scripts].merge!(
      'client:start': "yarn --cwd #{client_dir} start",
      'client:build': "yarn --cwd #{client_dir} build",
      'client:install': "yarn --cwd #{client_dir} install"
    )
  end
end

def update_client_package_name(client_dir: 'client')
  package_json = PackageJson.new('./package.json')
  rails_app_name = package_json.read[:name]
  client_name = "#{rails_app_name}-client"

  unless yes?("Update name of 'client' (cra) module? [#{client_name}]")
    client_name = ask "What do you want to call the 'client' app?"
  end

  client_package_json = PackageJson.new("./#{client_dir}/package.json")
  client_package_json.merge! name: client_name
end

#######################

run!