How to do a Post/Redirect/Get using Sinatra?

Question

What's Sinatra's equivalent of Rails' redirect_to method? I need to follow a Post/Redirect/Get flow for a form submission whilst preserving the instance variables that are passed to my view. The instance variables are lost when using the redirect method.

Answer 1

The Sinatra Book should clear your question. Especially the "Redirect" part.

Quoted from the book:

The redirect actually sends back a Location header to the browser, and the browser makes a followup request to the location indicated. Since the browser makes that followup request, you can redirect to any page, in your application, or another site entirely.

The flow of requests during a redirect is: Browser –> Server (redirect to ’/’) –> Browser (request ’/’) –> Server (result for ’/’)

Answer 2

Hi John,

Redirect in Sinatra is the most simple to use.

So the above code can explain

require 'rubygems'
require 'sinatra'

get '/' do
  redirect "http://yourawesomeurlhere.com
end

you can also redirect to another path in your current application like

(this sample with a delete method)

delete /delete_post' do
  redirect '/list_posts'
end

A very common place where this redirect instruction is used is under Authentication

def authorize!
  redirect '/login' unless authorized?
end

you can check more samples under:

Sinatra Manual: http://sinatra-book.gittr.com/

Faq: http://www.sinatrarb.com/faq.html

Extensions: http://www.sinatrarb.com/extensions.html

About your second question, passing variables into views, yep it's possible

so,

get '/pizza/:id' do
  # makeing lots of pizza
  @foo = Foo.find(params[:id])
  erb '%h1= @foo.name'
end

have fun