A experience on rack

sinatra-rack.ru

require 'sinatra-rack_app'

run Sinatra::Application

sinatra-rack_app.rb

require 'sinatra'

get '/' do
  puts ''
  puts '-> request uri: /'

  puts ''
  env.each do |k, v|
    puts "#{k} = #{v}"
  end
  puts ''  
    
  "Started up!"
end

get '/foo/:bar' do
  puts '-> request uri: /foo/:bar'

  "You asked for foo/#{params[:bar]}"
end

sinatra-rack_startup.rb

require 'rack'
require 'rack/rewindable_input'

# constants for environment variable -------------------------------------

RACK_VERSION      = "rack.version"
RACK_INPUT        = "rack.input"
RACK_ERRORS       = "rack.errors"
RACK_MULTITHREAD  = "rack.multithread"
RACK_MULTIPROCESS = "rack.multiprocess"
RACK_RUN_ONCE     = "rack.run_once"

REQUEST_METHOD    = "REQUEST_METHOD"
REQUEST_PATH      = "REQUEST_PATH"
PATH_INFO         = "PATH_INFO"
QUERY_STRING      = "QUERY_STRING"

rewindable_input = ::Rack::RewindableInput.new(STDIN)

# setup environment variable ---------------------------------------------

env                    = Hash.new

env[RACK_VERSION]      = [1, 0, 1]
env[RACK_INPUT]        = rewindable_input
env[RACK_ERRORS]       = STDERR
env[RACK_MULTITHREAD]  = false
env[RACK_MULTIPROCESS] = true
env[RACK_RUN_ONCE]     = false

env[REQUEST_METHOD]    = "GET"
env[REQUEST_PATH]      = "/"
env[PATH_INFO]         = "/"
env[QUERY_STRING]      = ""

# build application ------------------------------------------------------

app = Rack::Builder.new { eval ::File.read("sinatra-rack.ru") }.to_app

puts "started up: #{app}"

# process the request ----------------------------------------------------

puts "processing request: #{env[REQUEST_PATH]}"

status, headers, body = app.call env

rewindable_input.close

puts ""
puts "- status  = #{status}"
puts "- headers = #{headers}"
puts "- body    = #{body}"

trace

$ruby sinatra-rack_startup.rb

started up: Sinatra::Application
processing request: /

-> request uri: /

rack.version = [1, 0, 1]
rack.input = #<Rack::RewindableInput:0x271da20>
rack.errors = #<IO:0x1aa4980>
rack.multithread = false
rack.multiprocess = true
rack.run_once = false
REQUEST_METHOD = GET
REQUEST_PATH = /
PATH_INFO = /
QUERY_STRING =
rack.request.query_string =
rack.request.query_hash = {}
rack.request.form_input = #<Rack::RewindableInput:0x271da20>
rack.request.form_hash = {}
rack.request.form_vars =

- status  = 200
- headers = {"Content-Type"=>"text/html", "Content-Length"=>"11"}
- body    = #<Rack::CommonLogger:0x26132c0>