I'm getting “Heroku push rejected, no Rails or Rack app detected” error w/ Sinatra app

Question

I used the example hello world app here:

http://devcenter.heroku.com/articles/rack

And get the error "Heroku push rejected, no Rails or Rack app detected" Help?

Answer 1

You are missing a config.ru file. What you want to do is to create a file that looks like this: (it should be in the root of your repo)

# config.ru
require './your/app/file'

run MyApp

...where MyApp is your Sinatra app's class.

Be sure that your app file will not try to start ( MyApp.run! ) your app when require 'd:

# your_app_file.rb

class MyApp < Sinatra::Base
  ...
end

# Only run it when called as `ruby your_app_file.rb`
MyApp.run!  if $0 == __FILE__

Answer 2

Make sure you have these lines in your Gemfile

source 'http://rubygems.org'
gem 'sinatra'

Then:

bundle 

Then:

git push heroku master

Answer 3

This happened to me. It turned out it was because I initialized the Git repository in myproject/myapp/. Heroku needs the Git repository to be in myapp/. I deleted the.git folder in myproject/ (thus deleting that repository) and ran

cd myapp
git init

After that, it worked great.