Learning to build a complete application just by using RACK
- mkdir todo && cd todo
- create file config.ru
config.ru (the .ru stands for "rackup") is a Rack configuration file
put this code:
class Todo
def call(env)
[200, {"content-type" => "text/plain"}, ["Hello world!!"]]
end
end
run Todo.new
- run 'rackup'
- Create file in
lib/todo.rb&& copy "Todo" class there - back to config.ru
require "todo"
run Todo.new
- restart rack server
rackup -Ilib,-Ilibthat include lib directory. - any changes inside the lib directory you have to restart rack server. to get modifeed file, but if you want take modifeed file immediately use
Rack::Reloadermiddleware
require "todo"
# for reloading files if they have been modified.
# 0 mean talk changes after 0 sconde / immediately
use Rack::Reloader, 0
run Todo.new
let's go to lib/todo.rb
Replace this long line
[200, {"content-type" => "text/plain"}, ["Hello world!"]]
with this middleware, that will return html tag not text/plain" with to 200 status.
Rack::Response.new("Hello world!")
- update
lib/todo.rb
require "erb"
class Todo
def call(env)
Rack::Response.new(render("index.html.erb"))
end
def render(template)
path = File.expand_path("../../views/#{template}", __FILE__)
ERB.new(File.read(path)).result(binding)
end
end
- then create the template
/todo/views/index.html.erb
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html>
<head>
<title>My first rake app</title>
<style type="text/css">
body {
color: purple;
background-color: #d8da3d }
</style>
</head>
<body>
<h1>Hello World!!</h1>
</body>
</html>
inside call method lib/todo.rb
# Rack::Request, which also provides query string parsing and multipart handling.
request = Rack::Request.new(env)
case request.path
when '/' then Rack::Response.new(render("index.html.erb"))
else Rack::Response.new("Not Found", 404)
end
todo/lib/todo.rb
require "erb"
class Todo
def call(env)
# Rack::Request, which also provides query string parsing and multipart handling.
@request = Rack::Request.new(env)
case @request.path
when '/' then Rack::Response.new(render("index.html.erb"))
when '/create'
Rack::Response.new do |response|
response.set_cookie('task', @request.params['task'])
response.redirect("/")
end
else Rack::Response.new("Not Found", 404)
end
# Rack::Response, for convenient generation of HTTP replies and cookie handling.
end
def render(template)
path = File.expand_path("../../views/#{template}", __FILE__)
ERB.new(File.read(path)).result(binding)
end
def task
@request.cookies['task'] || "No task"
end
end
todi/views/index.html.erb inside body tag
<%= task %>
todo/config.ru
require "todo"
use Rack::Reloader, 0
run Todo
todo/lib/todo.rb
require "erb"
class Todo
def self.call(env)
new(env).responses.finish
end
def initialize(env)
# Rack::Request, which also provides query string parsing and multipart handling.
@request = Rack::Request.new(env)
end
def responses
case @request.path
when '/' then Rack::Response.new(render("index.html.erb"))
when '/create'
Rack::Response.new do |response|
response.set_cookie('task', @request.params['task'])
response.redirect("/")
end
else Rack::Response.new("Not Found", 404)
end
# Rack::Response, for convenient generation of HTTP replies and cookie handling.
end
def render(template)
path = File.expand_path("../../views/#{template}", __FILE__)
ERB.new(File.read(path)).result(binding)
end
def task
@request.cookies['task'] || "No task"
end
end
then restart rake server
- Add style link in the template
/todo/views/index.html.erb
<link type="text/css" href="/stylesheets/application.css" rel='stylesheet' />
- create css file public//stylesheets/application.css
body {
color: purple;
background-color: #d8da3d;
}
- update
todo/config.ru
require "todo"
# for reloading files if they have been modified.
# 0 mean talk changes after 0 sconde / immediately
use Rack::Reloader, 0
# Rack::Cascade, for trying additional Rack applications if an application returns a not found or method not supported response.
# Rack::Files, for serving static files.
run Rack::Cascade.new([Rack::File.new('public'), Todo])
- then restart rake server
add these lines after use Rack::Reloader, 0
use Rack::Auth::Basic do |username, password|
password == '123'
end