diff options
Diffstat (limited to 'lib/chef/run_list/run_list_expansion.rb')
-rw-r--r-- | lib/chef/run_list/run_list_expansion.rb | 191 |
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 |