Wrong Version of Ruby or Rake in App
Last updated November 15, 2017
Table of Contents
When trying to run a command on your app such as
$ heroku run bash
~$ rails c
You may get an error such as:
Could not find rake-12.0.0 in any of the sources
Run bundle install to install missing gems.
This does not mean that your specifed version of the gem is not installed on the dyno—it usually points to a path or configuration problem.
Bad binstubs
In recent versions of Rails the commands are in the form of “binstubs” these are files in the bin directory of your app. So when you run bin/rails c you should be able to start a console. There may be a problem with the code in your binstubs, you can update it by running this command locally:
$ bundle exec rake rails:update:bin
Then commit the results. Depending on your version of rails and the installed gems you should get a directory that looks something like this:
$ ls bin
bundle puma pumactl rails rake setup spring update
Make sure that bundle, rails, and rake are all present. This is an example of what a bin/rails file looks like in Rails 5.0.1
$ cat bin/rails
#!/usr/bin/env ruby
APP_PATH = File.expand_path('../config/application', __dir__)
require_relative '../config/boot'
require 'rails/commands'
Bad PATH
In UNIX like systems the PATH is how your operating system finds the correct file to execute. When you type a command like rake it searches each location on the PATH to see if it has an executable file by that name and then executes it. You can see where the file lives by executing which <command> such as which rake.
We highly recommend you do not modify your PATH environment variable, this should be maintained for you by our buildpack and build system
Check that you do not have a path config var set, it is not needed and can be actively harmful to the sytem:
$ heroku config
# ...
If you see PATH or GEM_PATH please remove them with heroku config:unset PATH GEM_PATH.