Running a Ruby script via web

Question

I am following the Rails Tutorial by Michael Hart and I am already on Chapter 7. But I wanna do something different right now, which the tutorial doesn't teach. I wanna run a script file inside my webpage. How I can do that? I saw other posts here saying to use Sinatra, but since I am following this tutorial I don't think it is such a good idea to use it because it can make everything different from the tutorial.

Here is the simple script I wanna run on my webpage:

#Somando idades
def soma_vetor_excluindo(index,vet) 
 soma = 0 
 for i in 0..9
 if(i!=index)
 soma = soma + vet[i].to_i
 end 
 end 
 return soma 
end
def soma_vetor(vet) 
 soma = 0 
 for i in 0..9
 soma = soma + vet[i].to_i 
 end 
 return soma 
end
def maior_vetor(vet) 
 maior = 0 
 for i in 0..9
 if(maior < vet[i])
 maior = vet[i]
 end 
 end 
 return maior 
end
idades = (0..9).collect{rand(99)+1}
soma_idades = (0..9).collect{0} soma = 0
print "#{idades} \n"
for i in 0..9 
 soma_idades[i] = soma_vetor_excluindo(i,idades) 
end
print "#{soma_idades} \n"
div = soma_vetor(soma_idades) / 9
resp = div - maior_vetor(soma_idades)
puts "#{resp}"

• MCB: for i in x isn't the 'Ruby' way. You'll want to change it to (0..9).each { |i| my_method(i) } or "do/end" if it's multiline.
• MCB: Also, look at Ruby's inject method for summing an array and for getting the highest value you can arr.sort{|x,y|y<=>x}.first Now, where do you want the output from print and puts to show up? If you want to program client side (in the users' browser) you use javascript.

Answer 1

The simplest way to do it would be to make the method soma_vetor_excluindo, soma_vetor, maior_vetor, etc, controller methods, so when you send data through a form or ajax, the action would trigger, calculate the values and return you a result.

Knowing this, you can have a controller, let's say MathController.rb, and inside it, the soma_vetor_excluindo method:

class MathController < ApplicationController
 def soma_vetor_excluindo
 end
 def soma_vetor
 end
 def maior_vetor
 end
end

To access this, you probably need a route, so on your routes.rb add something like this:

get 'math/soma_vetor_excluindo/:index/:vet', to 'math#soma_vetor_excluindo'
get 'math/soma_vetor/:vet', to 'math#soma_vetor'
get 'math/maior_vetor/:vet', to 'math#maior_vetor'

This means that when your browser hit localhost/math/soma_vetor_excluindo/1/2 or the other urls, it would send a get request to the controller calling the soma_vetor_excluindo method and putting in the parameters, params[:index] and params[:vet], so theoretically the script would run.

The thing is, you can adapt your controller to do something like this with very little work.

• Marcell Almeida: How I can make "soma_vetor_excluindo" a controller method?
• MurifoX: I used calculate just to simplify things. You can call it soma_vetor_excluindo. Lemme edit it.
• Marcell Almeida: First of all, thanks for helping me out! But I still can't figure out how to solve this. Maybe I am too newbie.Here is how it is looking right now: I created a static page for the script called "2011question6" So on my static_pages_controller.rb I got def minigame @title = "2011question6" end I've created the MathController as you said. But if I insert what you said to routes.rb my website breaks. So I don't know what to put on routes.rb. Right now I'm only with the static page on routes.rb match '/2011question6page', to: 'static_pages#2011question6page', via: 'get'
• kobaltz: I do this when I need to access certain services on my server. In my case, I have urls like admin/:service.:action => "admin#service" so if the authenticated user goes to something like admin/mailer.restart it will call my admin controller's service action. From there, I put the logic to stop, start, restart, or whatever the specified service.

Answer 2

I believe the simplest solution is to load a page per script. First you add a path for your script into the routes.rb with something like:

get 'scripts/your_script', to 'scripts#your_script

And in the controller (app/scripts_controller.rb) you should add your code like this:

class ScriptsController < ApplicationController
 #Somando idades
 def soma_vetor_excluindo(index,vet) 
 soma = 0 
 for i in 0..9
 if(i!=index)
 soma = soma + vet[i].to_i
 end 
 end 
 return soma 
 end
 def soma_vetor(vet) 
 soma = 0 
 for i in 0..9
 soma = soma + vet[i].to_i 
 end 
 return soma 
 end
 def maior_vetor(vet) 
 maior = 0 
 for i in 0..9
 if(maior < vet[i])
 maior = vet[i]
 end 
 end 
 return maior 
 end
 def your_script
 idades = (0..9).collect{rand(99)+1}
 soma_idades = (0..9).collect{0} 
 soma = 0
 answer = "#{idades} \n"
 for i in 0..9 
 soma_idades[i] = soma_vetor_excluindo(i,idades) 
 end
 answer << "#{soma_idades} \n"
 div = soma_vetor(soma_idades) / 9
 resp = div - maior_vetor(soma_idades)
 answer << "#{resp}"
 render(text: answer)
 end
end

when you access the page scripts/your_script, it should render a plain text presentation of your script result.

Although this is not the most elegant solution, it should solve your problem.