Sinatra example for ember-cli-deploy-mysql

ember-cli-deploy-mysql-sinatra.rb

require 'sinatra'
require 'sequel'
require 'mysql2'

configure do
  # Define your database, table, and revision preview query parameter here!
  set :database, Sequel.connect ENV.fetch('DATABASE_URL')
  set :table, :foo_bootstrap
  set :param_key, 'preview'
end

helpers do
  def fetch_index
    stack = []
    indexes = settings.database
      .from(settings.table)
      .to_hash(:key, :value)

    stack.push params.fetch(settings.param_key, 'current')
    while value = indexes[stack.last]
      return [value, stack.last] if value =~ /\s/
      break if stack.include? value # cycle guard
      stack.push value
    end

    not_found 'Invalid Site Index'
  end

  def extract_http_equiv!(content)
    modified_content = content.dup
    content.scan(/<\s*meta\s+http-equiv="?([\w-]+)"?\s+content="?(.+?)"?\s*>/im) do |pairs|
      yield pairs
      modified_content.slice! $&
    end
    content.replace modified_content
  end
end

get '/', :provides => :html do
  index, revision = fetch_index
  
  etag revision
  expires 3_600, :public
  extract_http_equiv!(index) do |key, value|
    response[key] = value
  end
  index.gsub(/\n */, '')
end

See also ember-cli-deploy-redis-sinatra.rb.