Distribution gems affects OpenNebula

[vholer]

Description
Although we are using our own gem location (/usr/share/one/gems-dist) with all packaged Ruby dependencies to simplify installation and isolate from gems installed in the system (via distribution packages or gem tool), it looks like we still might be affected by clashing gems installed in the system. E.g., Sinatra and Rack on Debian-like systems:

root@ubuntu1804-kvm-ssh-5-10-3-828bf-0:~# dpkg -l | egrep '(-rack|sinatra)'
ii  opennebula-rubygem-rack               2.0.7-5.10.3-1                              all          Rack provides a minimal, modular and adaptable interface for developing
ii  opennebula-rubygem-rack-protection    2.0.7-5.10.3-1                              all          Protect against typical web attacks, works with all Rack apps, including Rails.
ii  opennebula-rubygem-sinatra            2.0.7-5.10.3-1                              all          Sinatra is a DSL for quickly creating web applications in Ruby with minimal effort.
ii  ruby-rack                             1.6.4-4ubuntu0.1                            all          modular Ruby webserver interface
ii  ruby-rack-protection                  1.5.3-2+deb9u1build0.18.04.1                all          Protects against typical web attacks for Rack apps
ii  ruby-sinatra                          1.4.8-1                                     all          Ruby web-development dressed in a DSL

root@ubuntu1804-kvm-ssh-5-10-3-828bf-0:~# GEM_HOME=/usr/share/one/gems-dist/ GEM_PATH=/usr/share/one/gems-dist irb
irb(main):001:0> require 'sinatra'
/usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/show_exceptions.rb:16: warning: already initialized constant Rack::ShowExceptions::CONTEXT
/usr/lib/ruby/vendor_ruby/rack/showexceptions.rb:16: warning: previous definition of CONTEXT was here
/usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/show_exceptions.rb:114: warning: already initialized constant Rack::ShowExceptions::TEMPLATE
/usr/lib/ruby/vendor_ruby/rack/showexceptions.rb:115: warning: previous definition of TEMPLATE was here
=> true

irb(main):002:0> use Rack::Session::Pool, :key => 'sunstone'
Traceback (most recent call last):
       12: from /usr/bin/irb:11:in `<main>'
       11: from (irb):2
       10: from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
        9: from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
        8: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/pool.rb:6:in `<top (required)>'
        7: from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
        6: from /usr/lib/ruby/2.5.0/rubygems/core_ext/kernel_require.rb:59:in `require'
        5: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/abstract/id.rb:10:in `<top (required)>'
        4: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/abstract/id.rb:12:in `<module:Rack>'
        3: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/abstract/id.rb:14:in `<module:Session>'
        2: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/abstract/id.rb:200:in `<module:Abstract>'
        1: from /usr/share/one/gems-dist/gems/rack-2.0.7/lib/rack/session/abstract/id.rb:202:in `<class:Persisted>'
NameError (uninitialized constant Rack::Session::Abstract::Persisted::RACK_SESSION)

Expected behavior
Wrong version of (Rack/Sinatra) gem installed system-wide doesn't affect OpenNebula (Sunstone).

Details

• Version: 5.10.0

Progress Status

• Branch created
• Code committed to development branch
• Testing - QA
• Documentation
• Release notes - resolved issues, compatibility, known issues
• Code committed to upstream release/hotfix branches
• Documentation committed to upstream release/hotfix branches

[mreschke]

I am performing a fresh install of OpenNebula 5.10 on Debian 9 and ran into this exact issue. I cannot start systemctl start opennebula-sunstone or run it manually /usr/bin/ruby /usr/lib/one/sunstone/sunstone-server.rb. I just installed OpenNebula according to http://docs.opennebula.io/5.10/deployment/opennebula_installation/frontend_installation.html#ignc and I did NOT install_gems. I performed the exact same install (via ansible, so 100% exact) on a fresh Debian 10 system and sunstone starts perfectly. Is there no way to get sunstone working on Debian 9 right now, even with a patch to one of the RB files? I just performed an upgrade on a production debian 9 system from 5.6 to 5.10 and now I can't start sunstone. Would hate to reverse the upgrade just for this issue.

[mreschke]

Just an FYI, my hacky fix for my Debian 9 upgraded system.

I installed rbenv as the oneadmin user and rbenv install 2.5.5 on Debian 9 instead of the 2.3.3 and changed the /usr/bin/ruby symlink to point to /var/lib/one/.rbenv/shims/ruby. Unlinked the /usr/share/one/gems and ran the ./install_gems on the context of my oneadmin's rbenv 2.5.5 shell. Now my sudo systemctl start opennebula-sunstone or sudo /usr/bin/ruby /usr/lib/one/sunstone/sunstone-server.rb now works without the Rack error.

[vholer]

Fixed in master (target stable 5.12.0) by removing vendor / site directories d064ee6.

For 5.10.x, the workaround is to uninstall clashing distribution packages
http://docs.opennebula.io/5.10/intro_release_notes/release_notes/known_issues.html#opennebula-services-fail-to-start