shrtn.rb

require 'sinatra'
require 'redis'
require 'sinatra/flash'

configure do
	SiteConfig = OpenStruct.new(
		:title => 'shrtn » url shortener',
		:author => 'Denny Mueller',
		:url_base => 'http://localhost:4567/', # the url of your application
		:username => 'admin',
		:token => 'maketh1$longandh@rdtoremember',
		:password => 'password'
	)
end

enable :sessions
set :session_secret, '*&(^B234'

r = Redis.new

helpers do
	include Rack::Utils
	alias_method :h, :escape_html

	def random_string(length)
		rand(36**length).to_s(36)
	end

	def get_site_url(short_url)
		SiteConfig.url_base + short_url
	end

	def admin?
		request.cookies[SiteConfig.username] == SiteConfig.token
	end

	def protected!
		redirect '/login' unless admin?
	end
end

get '/' do
	erb :index
end

post '/' do
	if params[:url] and not params[:url].empty?
		unless params[:url] =~ /[a-zA-Z]+:\/\/.*/
			seconds = 60
			unless params[:url] =~ /\+(\d+)min/
				expire = 259200 # seconds have 3 days 
			else
				expire = params[:url].match(/\+(\d+)min/)[1]
			end
			params[:url] = "http://#{params[:url]}".gsub(/\+(\d+)min/,"")
			expire = expire.to_i*seconds
		end
		@shortcode = random_string 5
		r.MULTI do
			r.SET "links:#{@shortcode}", params[:url], :nx => true, :ex => expire
			r.SET "clicks:#{@shortcode}", "0", :nx => true, :ex => expire
		end
	end
	erb :index
end

get '/login' do
	erb :login
end

post '/login' do
	if params[:username]==SiteConfig.username&&params[:password]==SiteConfig.password
			response.set_cookie(SiteConfig.username,SiteConfig.token) 
			redirect '/admin'
		else
			flash[:error] = "Wrong Login Data!"
			redirect '/admin'
		end
end

get '/logout' do
	response.set_cookie(SiteConfig.username, false)
	redirect '/'
end

get '/admin' do
	protected!
	seconds = 60
	@count = r.EVAL("return #redis.call('keys', 'links:*')")
	@url_shortcodes = r.KEYS("links:*")
	@clicks = [] ; @urls = [] ; @timeouts = [] #init arrays
	@url_shortcodes.each do |shortcode|
		shortcode.slice! "links:"
		@urls << r.GET("links:#{shortcode}")
		@clicks << r.GET("clicks:#{shortcode}")
		@timeouts << r.TTL("links:#{shortcode}"))/seconds
	end
	erb :admin
end

get '/:shortcode' do
	@url = r.GET "links:#{params[:shortcode]}"
	if !@url.nil?
		r.INCR "clicks:#{params[:shortcode]}"
		redirect @url
	else
		flash[:error] = "Ups, Something went wrong!"
		redirect '/'
	end
end