Upgrade to version 2.7.1 breaks newrelic.

I followed the upgrade steps for 2.7.1, but new relic no longer works. It seems to be failing with a syntax error on both development and production.

Here’s part of the mongrel log on development:

---------------------------------------------------------------------------
** Starting Rails with development environment...
** [NewRelic] New Relic RPM Agent 2.7.1 Initialized: pid = 32042
** [NewRelic] Agent Log is found in /mnt/spangulu/projects/wedding/trunk/log/newrelic_agent.3004.log
** [NewRelic] Error initializing New Relic plugin (can't convert Array into String)
** [NewRelic] /mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/agent/agent.rb:285:in `glob'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/agent/agent.rb:285:in `instrument_app'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/agent/agent.rb:440:in `start_reporting'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/agent/agent.rb:178:in `start'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/config.rb:125:in `start_agent'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/lib/new_relic/config/rails.rb:25:in `start_plugin'
/mnt/spangulu/projects/wedding/trunk/vendor/plugins/newrelic_rpm/init.rb:19:in `evaluate_init_rb'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin.rb:79:in `evaluate_init_rb'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin.rb:75:in `evaluate_init_rb'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin.rb:39:in `load'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin/loader.rb:33:in `load_plugins'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin/loader.rb:32:in `each'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/rails/plugin/loader.rb:32:in `load_plugins'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/initializer.rb:189:in `load_plugins'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/initializer.rb:105:in `process'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/initializer.rb:49:in `send'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/initializer.rb:49:in `run'
/mnt/spangulu/projects/wedding/trunk/config/environment.rb:15
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:496:in `require'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:342:in `new_constants_in'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:496:in `require'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/rails.rb:155:in `rails'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/mongrel_rails:112:in `cloaker_'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:138:in `call'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:138:in `listener'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/mongrel_rails:98:in `cloaker_'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:51:in `call'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/configurator.rb:51:in `initialize'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/mongrel_rails:83:in `new'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/mongrel_rails:83:in `run'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/command.rb:211:in `run'
/usr/lib/ruby/gems/1.8/gems/mongrel-1.0.1/bin/mongrel_rails:243
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:489:in `load'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:489:in `load'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:342:in `new_constants_in'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:489:in `load'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/commands/servers/mongrel.rb:64
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:496:in `require'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:342:in `new_constants_in'
/usr/lib/ruby/gems/1.8/gems/activesupport-2.0.2/lib/active_support/dependencies.rb:496:in `require'
/usr/lib/ruby/gems/1.8/gems/rails-2.0.2/lib/commands/server.rb:39
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require'
/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:27:in `require'
script/server:3
** [NewRelic] Agent is disabled.
---------------------------------------------------------------------------

We’re running ruby 1.8.5 – it worked fine before version 2.7.1 but no longer. If you look at the above, it is a bug in the Dir.glob usage in agent.rb:

The important code, in agent.rb:

instrumentation_path = File.join(File.dirname(__FILE__), 'instrumentation')
instrumentation_files = [ ] <<
File.join(instrumentation_path, '*.rb') <<
File.join(instrumentation_path, config.app.to_s, '*.rb')

Dir.glob(instrumentation_files) do |file|
begin
require file
log.debug "Processed instrumentation file '#{file.split('/').last}'"
rescue => e
log.error "Error loading instrumentation file '#{file}': #{e}"
log.debug e.backtrace.join("\n")
end
end

Dir.glob expects a string but is getting an array...