Added resource store for dsc

This is a cache that will be used to lookup the module name for resources.
If in the future we decide to do any validation, the data for that can is
available.

1 files changed, 114 insertions, 0 deletions

diff --git a/lib/chef/util/dsc/resource_store.rb b/lib/chef/util/dsc/resource_store.rb
new file mode 100644
index 0000000000..3adc763483
--- /dev/null
+++ b/lib/chef/util/dsc/resource_store.rb
@@ -0,0 +1,114 @@
+#
+# Author:: Jay Mundrawala (<jdm@chef.io>)
+#
+# Copyright:: Copyright (c) 2015 Chef Software, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require 'chef/util/powershell/cmdlet'
+require 'chef/util/powershell/cmdlet_result'
+
+class Chef
+class Util
+class DSC
+  class ResourceStore
+
+    def self.instance
+      @@instance ||= ResourceStore.new.tap do |store|
+        store.send(:populate_cache)
+      end
+    end
+
+    def resources
+      @resources ||= []
+    end
+
+    def resource(name, module_name=nil)
+      found = find_resources(name, module_name, resources)
+
+      # We don't have it, query for the resource...it might
+      # have been added since we last queried
+      if found.length == 0
+        rs = query_resource(name)
+        add_resources(rs)
+        found = find_resources(name, module_name, rs)
+      end
+
+      case found.length
+      when 0
+        nil
+      when 1
+        found[0]
+      else
+        raise 'Multiple matching resources'
+      end
+    end
+
+    private
+
+    def add_resource(new_r)
+      count = resources.count do |r|
+        r['ResourceType'].casecmp(new_r['ResourceType']) == 0
+      end
+      if count == 0
+        resources << new_r
+      end
+    end
+
+    def add_resources(rs)
+      rs.each do |r|
+        add_resource(r)
+      end
+    end
+
+    def populate_cache
+      @resources = query_resources
+    end
+
+    def find_resources(name, module_name, rs)
+      found = rs.find_all do |r|
+        name_matches = r['FriendlyName'].casecmp(name) == 0
+        if name_matches
+          module_name == nil || (r['Module'] and r['Module']['Name'].casecmp(module_name) == 0)
+        else
+          false
+        end
+      end
+    end
+
+
+    # Returns a list of dsc resources
+    def query_resources
+      cmdlet = Chef::Util::Powershell::Cmdlet.new(nil, 'get-dscresource',
+          :object)
+      result = cmdlet.run
+      result.return_value
+    end
+
+    # Returns a list of dsc resources matching the provided name
+    def query_resource(resource_name)
+      cmdlet = Chef::Util::Powershell::Cmdlet.new(nil, "get-dscresource #{resource_name}",
+          :object)
+      result = cmdlet.run
+      ret_val = result.return_value
+      if ret_val.is_a? Array
+        ret_val
+      else
+        [ret_val]
+      end
+    end
+  end
+end
+end
+end