Ensure that we don't break when Windows registry is missing our keys

This situation is common when using HFTs where the registry will be
empty initially. Here we just ensure that errors result in no fatal
paths to make sure that HFTs can work properly.

CHANGELOG.md

@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Fixed
 - Fix windows credential search for HFT-created identities.
   [cyberark/conjur-puppet#47](https://github.com/org/repo/issues/47)
+- Fix windows registry exceptions on new HFT-based hosts
+  [cyberark/conjur-puppet#112](https://github.com/org/repo/issues/112)
 
 ## [2.0.3] - 2020-05-10
 ### Changed

lib/conjur/puppet_module/config.rb

@@ -27,12 +27,21 @@ def from_registry
             unless Puppet.features.microsoft_windows?
 
           require 'win32/registry'
-          c = Win32::Registry::HKEY_LOCAL_MACHINE.open(REG_KEY_NAME) do |reg|
-            # Convert registry value names from camel case to underscores
-            # e.g. ApplianceUrl => appliance_url
-            reg.map { |name, _type, data|  [name.gsub(/(.)([A-Z])/, '\1_\2').downcase, data] }.to_h
+
+          c = {}
+          begin
+            Win32::Registry::HKEY_LOCAL_MACHINE.open(REG_KEY_NAME) do |reg|
+              # Convert registry value names from camel case to underscores
+              # e.g. ApplianceUrl => appliance_url
+              c = reg.map { |name, _type, data|  [name.gsub(/(.)([A-Z])/, '\1_\2').downcase, data] }.to_h
+            end
+          rescue
+            Puppet.warning "Agent’s registry did not contain path #{REG_KEY_NAME}. If this is the " +
+              "first time using HFTs on this node, this is expected behavior."
           end
+
           c['ssl_certificate'] ||= File.read c['cert_file'] if c['cert_file']
+
           c
         end
       end