lib/radiant/.svn/text-base/extension_loader.rb.svn-base

   1 require 'radiant/extension'
   2 require 'method_observer'
   3
   4 module Radiant
   5   class ExtensionLoader
   6
   7     class DependenciesObserver < MethodObserver
   8       attr_accessor :config
   9
  10       def initialize(rails_config)
  11         @config = rails_config
  12       end
  13
  14       def before_clear(*args)
  15         ExtensionLoader.deactivate_extensions
  16       end
  17
  18       def after_clear(*args)
  19         ExtensionLoader.load_extensions
  20         ExtensionLoader.activate_extensions
  21       end
  22     end
  23
  24     include Simpleton
  25
  26     attr_accessor :initializer, :extensions
  27
  28     def initialize
  29       self.extensions = []
  30     end
  31
  32     def configuration
  33       initializer.configuration
  34     end
  35
  36     def extension_load_paths
  37       load_extension_roots.map { |extension| load_paths_for(extension) }.flatten.select { |d| File.directory?(d) }
  38     end
  39
  40     def plugin_paths
  41       load_extension_roots.map {|extension| "#{extension}/vendor/plugins" }.select {|d| File.directory?(d) }
  42     end
  43
  44     def add_extension_paths
  45       extension_load_paths.reverse_each do |path|
  46         configuration.load_paths.unshift path
  47         $LOAD_PATH.unshift path
  48       end
  49     end
  50
  51     def add_plugin_paths
  52       configuration.plugin_paths.concat plugin_paths
  53     end
  54
  55     def controller_paths
  56       extensions.map { |extension| "#{extension.root}/app/controllers" }.select { |d| File.directory?(d) }
  57     end
  58
  59     def add_controller_paths
  60       configuration.controller_paths.concat(controller_paths)
  61     end
  62
  63     def view_paths
  64       extensions.map { |extension| "#{extension.root}/app/views" }.select { |d| File.directory?(d) }
  65     end
  66
  67     # Load the extensions
  68     def load_extensions
  69       @observer ||= DependenciesObserver.new(configuration).observe(::Dependencies)
  70       self.extensions = load_extension_roots.map do |root|
  71         begin
  72           extension_file = "#{File.basename(root).sub(/^\d+_/,'')}_extension"
  73           extension = extension_file.camelize.constantize
  74           extension.unloadable
  75           extension.root = root
  76           extension
  77         rescue LoadError, NameError => e
  78           $stderr.puts "Could not load extension from file: #{extension_file}.\n#{e.inspect}"
  79           nil
  80         end
  81       end.compact
  82     end
  83
  84     def deactivate_extensions
  85       extensions.each &:deactivate
  86     end
  87
  88     def activate_extensions
  89       initializer.initialize_default_admin_tabs
  90       # Reset the view paths after
  91       initializer.initialize_framework_views
  92       extensions.each &:activate
  93     end
  94     alias :reactivate :activate_extensions
  95
  96     private
  97
  98       def load_paths_for(dir)
  99         if File.directory?(dir)
 100           %w(lib app/models app/controllers app/helpers test/helpers).collect do |p|
 101             path = "#{dir}/#{p}"
 102             path if File.directory?(path)
 103           end.compact << dir
 104         else
 105           []
 106         end
 107       end
 108
 109       def load_extension_roots
 110         @load_extension_roots ||= unless configuration.extensions.empty?
 111           select_extension_roots
 112         else
 113           []
 114         end
 115       end
 116
 117       def select_extension_roots
 118         all_roots = all_extension_roots.dup
 119
 120         roots = configuration.extensions.map do |ext_name|
 121           if :all === ext_name
 122             :all
 123           else
 124             ext_path = all_roots.detect do |maybe_path|
 125               File.basename(maybe_path).sub(/^\d+_/, '') == ext_name.to_s
 126             end
 127             raise LoadError, "Cannot find the extension '#{ext_name}'!" if ext_path.nil?
 128             all_roots.delete(ext_path)
 129           end
 130         end
 131
 132         if placeholder = roots.index(:all)
 133           # replace the :all symbol with any remaining paths
 134           roots[placeholder, 1] = all_roots
 135         end
 136         roots
 137       end
 138
 139       def all_extension_roots
 140         @all_extension_roots ||= configuration.extension_paths.map do |path|
 141           Dir["#{path}/*"].map {|f| File.expand_path(f) if File.directory?(f) }.compact.sort
 142         end.flatten
 143       end
 144   end
 145 end