Possible issue with chruby-exec in Ubuntu?

[kgrz]

We're trying to provide support for the invoker gem on Linux with chruby, as requested here. A bit of background about invoker:

1. It's a mashup of the features of Pow web server and Foreman task runner.
2. The gem is installed without sudo which means chruby will place the executable under ~/.gem/ruby/<version>/bin.
3. After installation, the next step is running sudo invoker setup. This is straight forward in OSX since sudo gem env and gem env are same. However, on Linux, the sudo-ed command should be run by the command listed in the issue sudo -E chruby-exec 2.1.2 -- invoker setup.

However, that command returns an error saying the executable invoker was not found. The outputs of env, gem env and $PATH when using sudo chruby-exec ... and without it are listed in this gist. You can see that the output of echo $PATH under sudo -E chruby-exec and without it are the same. However, the PATH key in the output of env is different.

Solutions to make the invoker gem to work are these:

1. Install the gem using the command gem install invoker --bindir $RUBY_ROOT/bin and the n run sudo -E chruby-exec 2.1.2 -- invoker setup. or

2. Install with gem install invoker and run the sudo invoker setup part with this command:

   sudo -E chruby-exec 2.1.2 -- ~/.gem/ruby//bin/invoker setup

Which is pretty tasking.

My question is, why isn't chruby-exec not loading binaries under ~/.gem/ruby/version/bin when run with sudo -E? Is this a design choice?

OS: Ubuntu 14.04
Ruby: ruby 2.1.2p95 (2014-05-08 revision 45877) [x86_64-linux]

[postmodern]

chruby will not add ~/.gem/... to $GEM_PATH when you are root. The idea being, if you are installing gems as root, you probably want to install them in the rubies own gemdir. Also, it's generally not a good idea to invoke user binaries with sudo.

[postmodern]

Perhaps you could do something like chruby-exec 2.1.2 -- sudo -E .... Although, it appears sudo -E is still clobbering $PATH.

[gnufied]

@postmodern The gem is not being installed as root btw. What we want is able to execute binary provided by gem via sudo . it should ideally work as documented here - https://github.com/postmodern/chruby/wiki/Sudo

Are we considering binaries provided by stock ruby to be safer than those provided by gems? I don't see why binaries installed in RUBY_ROOT works but not in gem root. The distinction seems arbitrary and entirely out of scope for something like chruby.

[gnufied]

sudo -E clobbers $PATH and other environment variables depending on security policy of operating system btw. But if chruby is at all meant to be used via sudo the workarounds should work.

[shaneog]

Note that I had the issue on OS X.

The gem installed fine, but when called using sudo without -E the setup wouldn't run due to path errors.