run controller before rendering html ruby on rails

Question

In my rails app, HTML is rendered before controller completely runs. I want index method in controller to first run completely before rendering HTML. I was able to achieve this by adding <% sleep(x) %> at the beginning of the HTML page but i want to do it without using it. can anyone suggest a way to accomplish this?

Thanks

Erm, do you mean you want the action method on your controller to do something after it's rendered the page? — Tony Hopkinson, Jun 09 '14 at 11:39
no i want index method to execute before rendering the pagedef index @data=Csvtest.all @length=@data.length-1 @resp=[] threads = (0..@length-1).map do |i| #services are pinged concurrently Thread.new(i) do |i| @resp[i]=%x{curl -sL -w "%{http_code}" #{@data[i]['url']} -o /dev/null}.to_i #@response contains status code end end end — Abhinav Kulkarni, Jun 09 '14 at 11:42
You can't do this. The page is rendered INSIDE the action: that's what the action does - it runs a bit of code (the code you can see in your action) and then renders the page. The rendering happens inside the action. I think you need to take a step back and explain why you want to do this. — Max Williams, Jun 09 '14 at 11:54
U r making curl request in controller. Better do it via ajax (after rendering page) and show loader till response comes. — Neeraj, Jun 09 '14 at 11:54
@Neeraj It depends on the endpoint of his curl, if it is not on his current domain. There is a problem with cross-origin policy in the ajax call. You can find more here http://stackoverflow.com/questions/3076414/ways-to-circumvent-the-same-origin-policy — edariedl, Jun 09 '14 at 12:08

score 1 · Accepted Answer · answered Jun 09 '14 at 11:53

From the comment above you are using this index action:

def index 
  @data=Csvtest.all
  @length=@data.length-1 
  @resp=[] 
  threads = (0..@length-1).map do |i| #services are pinged concurrently 
    Thread.new(i) do |i| 
      @resp[i] = %x{curl -sL -w "%{http_code}" #{@data[i]['url']} -o /dev/null}.to_i #@response contains status code 
    end 
  end 
end

You are forgetting to say main thread to wait before all other threads terminates. You should call

threads.each { |t| t.join }

It tells, main thread wait until all of concurrent threads will pass to the end and than continue.

run controller before rendering html ruby on rails

1 Answers1