rack-app example for main page

config.ru

require 'json'
require 'rack/app'
class MyApp < Rack::App
  
  headers 'Access-Control-Allow-Origin' => '*',
          'Access-Control-Expose-Headers' => 'X-My-Custom-Header, X-Another-Custom-Header'

  serializer do |obj|
    if obj.is_a?(String)
      obj
    else
      JSON.dump(obj)
    end
  end

  error StandardError, NoMethodError do |ex|
    { error: ex.message }
  end

  get '/bad/endpoint' do
    no_method_error_here
  end
  
  desc 'hello world endpoint'
  validate_params do
    required 'words', class: Array, of: String,
                      desc: 'words that will be joined with space',
                      example: %w(dog cat)
    required 'to', class: String,
                   desc: 'the subject of the conversation'
  end
  get '/validated' do
    return "Hello #{validated_params['to']}: #{validated_params['words'].join(' ')}"
  end

  get '/' do
    { hello: 'world' }
  end

  mount MediaFileServer, to: "/assets"
  mount Uploader, to: '/upload'
  
end

# for more check out how-to
run MyApp

media_file_server.rb

class MediaFileServer < Rack::App

  serve_files_from '/folder/from/project/root', to: '/files'

  get '/' do
    serve_file 'custom_file_path_to_stream_back'
  end
  
end

uploader.rb

require 'fileutils'
class Uploader < Rack::App 
  
  post '/to_stream' do 
    payload_stream do |string_chunk|  
      # do some work
    end 
  end 

  post '/upload_file' do
    file_path = Rack::App::Utils.pwd('/upliads', params['user_id'], params['file_name'])
    FileUtils.mkdir_p(file_path)
    payload_to_file(file_path) 
  end
  
  post '/memory_buffered_payload' do
    payload #> request payload string
  end
  
end