[OC-3564] move core Chef to the repo root \o/ \m/

The opscode/chef repository now only contains the core Chef library code
used by chef-client, knife and chef-solo!

1 files changed, 191 insertions, 0 deletions

diff --git a/lib/chef/run_list/run_list_expansion.rb b/lib/chef/run_list/run_list_expansion.rb
new file mode 100644
index 0000000000..7b8108a2d4
--- /dev/null
+++ b/lib/chef/run_list/run_list_expansion.rb
@@ -0,0 +1,191 @@
+#
+# Author:: Daniel DeLeo (<dan@opscode.com>)
+# Author:: Tim Hinderliter (<tim@opscode.com>)
+# Copyright:: Copyright (c) 2010, 2011 Opscode, Inc.
+# License:: Apache License, Version 2.0
+#
+# 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/mash'
+
+require 'chef/mixin/deep_merge'
+
+require 'chef/role'
+require 'chef/rest'
+
+class Chef
+  class RunList
+    # Abstract Base class for expanding a run list. Subclasses must handle
+    # fetching roles from a data source by defining +fetch_role+
+    class RunListExpansion
+
+      attr_reader :run_list_items
+
+      # A VersionedRecipeList of recipes. Populated only after #expand
+      # is called.
+      attr_reader :recipes
+
+      attr_reader :default_attrs
+
+      attr_reader :override_attrs
+
+      attr_reader :environment
+
+      attr_reader :missing_roles_with_including_role
+
+      # The data source passed to the constructor. Not used in this class.
+      # In subclasses, this is a couchdb or Chef::REST object pre-configured
+      # to fetch roles from their correct location.
+      attr_reader :source
+
+      # Returns a Hash of the form "including_role" => "included_role_or_recipe".
+      # This can be used to show the expanded run list (ordered) graph.
+      # ==== Caveats
+      # * Duplicate roles are not shown.
+      attr_reader :run_list_trace
+
+      def initialize(environment, run_list_items, source=nil)
+        @environment = environment
+        @missing_roles_with_including_role = Array.new
+
+        @run_list_items = run_list_items.dup
+        @source = source
+
+        @default_attrs = Mash.new
+        @override_attrs = Mash.new
+
+        @recipes = Chef::RunList::VersionedRecipeList.new
+
+        @applied_roles = {}
+        @run_list_trace = Hash.new {|h, key| h[key] = [] }
+      end
+
+      # Did we find any errors (expanding roles)?
+      def errors?
+        @missing_roles_with_including_role.length > 0
+      end
+
+      alias :invalid? :errors?
+
+      # Recurses over the run list items, expanding roles. After this,
+      # +recipes+ will contain the fully expanded recipe list
+      def expand
+        # Sure do miss function arity when being recursive
+        expand_run_list_items(@run_list_items)
+      end
+
+      # Fetches and inflates a role
+      # === Returns
+      # Chef::Role  in most cases
+      # false       if the role has already been applied
+      # nil         if the role does not exist
+      def inflate_role(role_name, included_by)
+        return false if applied_role?(role_name) # Prevent infinite loops
+        applied_role(role_name)
+        fetch_role(role_name, included_by)
+      end
+
+      def apply_role_attributes(role)
+        @default_attrs = Chef::Mixin::DeepMerge.role_merge(@default_attrs, role.default_attributes)
+        @override_attrs = Chef::Mixin::DeepMerge.role_merge(@override_attrs, role.override_attributes)
+      end
+
+      def applied_role?(role_name)
+        @applied_roles.has_key?(role_name)
+      end
+
+      # Returns an array of role names that were expanded; this
+      # includes any roles that were in the original, pre-expansion
+      # run_list as well as roles processed during
+      # expansion. Populated only after #expand is called.
+      def roles
+        @applied_roles.keys
+      end
+
+      # In subclasses, this method will fetch the role from the data source.
+      def fetch_role(name, included_by)
+        raise NotImplementedError
+      end
+
+      # When a role is not found, an error message is logged, but no
+      # exception is raised.  We do add an entry in the errors collection.
+      # === Returns
+      # nil
+      def role_not_found(name, included_by)
+        Chef::Log.error("Role #{name} (included by '#{included_by}') is in the runlist but does not exist. Skipping expand.")
+        @missing_roles_with_including_role << [name, included_by]
+        nil
+      end
+
+      def errors
+        @missing_roles_with_including_role.map {|item| item.first }
+      end
+
+      private
+
+      # these methods modifies internal state based on arguments, so hide it.
+
+      def applied_role(role_name)
+        @applied_roles[role_name] = true
+      end
+
+      def expand_run_list_items(items, included_by="top level")
+        if entry = items.shift
+          @run_list_trace[included_by.to_s] << entry.to_s
+
+          case entry.type
+          when :recipe
+            recipes.add_recipe(entry.name, entry.version)
+          when :role
+            if role = inflate_role(entry.name, included_by)
+              expand_run_list_items(role.run_list_for(@environment).run_list_items, role)
+              apply_role_attributes(role)
+            end
+          end
+          expand_run_list_items(items, included_by)
+        end
+      end
+
+    end
+
+    # Expand a run list from disk. Suitable for chef-solo
+    class RunListExpansionFromDisk < RunListExpansion
+
+      def fetch_role(name, included_by)
+        Chef::Role.from_disk(name)
+      rescue Chef::Exceptions::RoleNotFound
+        role_not_found(name, included_by)
+      end
+
+    end
+
+    # Expand a run list from the chef-server API.
+    class RunListExpansionFromAPI < RunListExpansion
+
+      def rest
+        @rest ||= (source || Chef::REST.new(Chef::Config[:role_url]))
+      end
+
+      def fetch_role(name, included_by)
+        rest.get_rest("roles/#{name}")
+      rescue Net::HTTPServerException => e
+        if e.message == '404 "Not Found"'
+          role_not_found(name, included_by)
+        else
+          raise
+        end
+      end
+    end
+
+  end
+end