OHAI-434: Order metadata versions with basic String/Array#sort

2 files changed, 4 insertions, 1 deletions

diff --git a/lib/ohai/mixin/ec2_metadata.rb b/lib/ohai/mixin/ec2_metadata.rb
index 0b750aae..0c66cf31 100644
--- a/lib/ohai/mixin/ec2_metadata.rb
+++ b/lib/ohai/mixin/ec2_metadata.rb
@@ -79,7 +79,10 @@ module Ohai
         unless response.code == '200'
           raise "Unable to determine EC2 metadata version (returned #{response.code} response)"
         end
+        # Note: Sorting the list of versions may have unintended consequences in
+        # non-EC2 environments. It appears to be safe in EC2 as of 2013-04-12.
         versions = response.body.split("\n")
+        versions = response.body.split("\n").sort
         until (versions.empty? || EC2_SUPPORTED_VERSIONS.include?(versions.last)) do
           pv = versions.pop
           Ohai::Log.debug("EC2 shows unsupported metadata version: #{pv}") unless pv == 'latest'
diff --git a/spec/unit/mixin/ec2_metadata_spec.rb b/spec/unit/mixin/ec2_metadata_spec.rb
index 9862b148..d327fabd 100644
--- a/spec/unit/mixin/ec2_metadata_spec.rb
+++ b/spec/unit/mixin/ec2_metadata_spec.rb
@@ -39,8 +39,8 @@ describe Ohai::Mixin::Ec2Metadata do
 
     context "with an unsorted list of metadata versions" do
       let(:response) { mock("Net::HTTP Response", :body => "1.0\n2009-04-04\n2007-03-01\n2011-05-01\n2008-09-01\nUnsupported", :code => "200") }
-      it "returns the most recent version" do
 
+      it "returns the most recent version (using string sort)" do
         mixin.best_api_version.should == "2011-05-01"
       end
     end