Deploying to Heroku with environment variables in Gemfile

问题

I've recently updated our Gemfile as pry-byebug and bye-bug were causing Rubymine to crash for some of my colleagues. Since there are some of us that use other editors I've added an environment variable to our Gemfile:

if ENV["USE_DEBUGGER"]
  gem "pry-byebug"
  gem "byebug"
end

This worked fine in our local machines but deploying to Heroku causes the following error: gist

I've tried running bundle install and committing a new Gemfile.lock but that changes nothing. Getting rid of the control flow declaration or simply removing the gems fixes the issue.It's worth nothing that in that same commit I bumped the required ruby version to 2.2.0

Is there any way to use conditional statements in the Gemfile without blowing Heroku up?

回答1:

Wrap the conditional in a group and try to BUNDLE_WITHOUT on deployment. ref

group :byebug do
  if ENV["USE_DEBUGGER"]
    gem "pry-byebug"
    gem "byebug"
  end
end

heroku config:add BUNDLE_WITHOUT="byebug"

回答2:

Alright so after juggling with RubyMine I realised the problem occurs when requireing pry and any other related debugging gems. I managed to fix this by updating my Gemfile to the following:

  if ENV["USE_DEBUGGER"]
    gem "pry-byebug"
    gem "byebug"
  else
    gem "pry-byebug", require: false
    gem "byebug", require: false
  end

I hope this helps anybody facing a similar issue.

来源：https://stackoverflow.com/questions/28172715/deploying-to-heroku-with-environment-variables-in-gemfile