Jira (PUP-10417) Custom Ruby functions that define a JSON module can ambiguate its scope and break Puppet

[Garrett Guillotte (Jira)]

Title: Message Title

Garrett Guillotte updated an issue   Puppet / PUP-10417 Custom Ruby functions that define a JSON module can ambiguate its scope and break Puppet Change By: Garrett Guillotte *Puppet Version:* Seen in Puppet 5 and 6 *Puppet Server Version:* N/A *OS Name/Version:* RHEL 7 If a custom function defines a Ruby module also used by Puppet (ie. {{module JSON}}), and other loaded modules attempt to use related functions (ie. JSON functions from {{stdlib}} that call {{JSON}}), they fail because Puppet runs the custom function code within the {{Puppet::Pops::Loader::RubyFunctionInstantiator}} scope instead of top scope: {code} 2020-03-18T00:00:29.762-05:00 ERROR [qtp802169583-480691] [puppetserver] Puppet Evaluation Error: Error while evaluating a Function Call, undefined method `pretty_generate' for Puppet::Pops::Loader::RubyFunctionInstantiator::JSON:Module (file: /etc/puppetlabs/code/environments/production/modules/npc_coreservices/manifests/components/cache_proxy/install.pp, line: 106, column: 22) on node pv20616cspgl01.npc.lan /etc/puppetlabs/code/environments/production/modules/stdlib/lib/puppet/functions/to_json_pretty.rb:36:in `to_json_pretty' /opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/pops/functions/dispatch.rb:60:in `invoke' /opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/pops/functions/dispatcher.rb:43:in `block in dispatch' org/jruby/RubyKernel.java:1180:in `catch' /opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/pops/functions/dispatcher.rb:42:in `dispatch' /opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/pops/functions/function.rb:46:in `block in call' org/jruby/RubyKernel.java:1180:in `catch' /opt/puppetlabs/puppet/lib/ruby/vendor_ruby/puppet/pops/functions/function.rb:45:in `call' /etc/puppetlabs/code/environments/production/modules/ npc_coreservices ... /manifests/components/cache_proxy/install.pp:106:in `<eval>' org/jruby/RubyKernel.java:1037:in `eval' ... {code} For example, a Puppet module with a custom Ruby function that declares: {code} require 'json' module JSON ... {code} and another Puppet module that attempts to prettify JSON via {{stdlib}}: {code} $json          = to_json_pretty($some_json_content) {code} can produce the above error. For another example, see: https://github.com/sensu/puppet-module-sensuclassic/issues/24 and the patch to work around it: https://github.com/sensu/puppet-module-sensuclassic/pull/25/files *Desired Behavior:* Users can define a Ruby JSON module in a custom function if necessary without breaking default behavior. *Actual Behavior:* {{stdlib}} doesn't explicitly defines the correct scope when invoking {{JSON}} (MODULES ticket tbd), so an {{eval()}} statement in {{RubyFunctionInstantiator}} executes the code within its scope instead. https://github.com/puppetlabs/puppet/blob/master/lib/puppet/pops/loader/ruby_function_instantiator.rb#L22 If custom Ruby functions cannot be guaranteed to run in the expected scope, or if module declarations are unsafe, this behavior should at a minimum be documented, and if possible the error messages should indicate the scope conflict. Add Comment   This message was sent by Atlassian Jira (v8.5.2#805002-sha1:a66f935) -- You received this message because you are subscribed to the Google Groups "Puppet Bugs" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-bugs+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/puppet-bugs/JIRA.354928.1586391583000.34484.1586391660037%40Atlassian.JIRA.