vendor/rails/railties/lib/rails_generator/scripts.rb

   1 require File.dirname(__FILE__) + '/options'
   2
   3 module Rails
   4   module Generator
   5     module Scripts
   6
   7       # Generator scripts handle command-line invocation.  Each script
   8       # responds to an invoke! class method which handles option parsing
   9       # and generator invocation.
  10       class Base
  11         include Options
  12         default_options :collision => :ask, :quiet => false
  13
  14         # Run the generator script.  Takes an array of unparsed arguments
  15         # and a hash of parsed arguments, takes the generator as an option
  16         # or first remaining argument, and invokes the requested command.
  17         def run(args = [], runtime_options = {})
  18           begin
  19             parse!(args.dup, runtime_options)
  20           rescue OptionParser::InvalidOption => e
  21             # Don't cry, script. Generators want what you think is invalid.
  22           end
  23
  24           # Generator name is the only required option.
  25           unless options[:generator]
  26             usage if args.empty?
  27             options[:generator] ||= args.shift
  28           end
  29
  30           # Look up generator instance and invoke command on it.
  31           Rails::Generator::Base.instance(options[:generator], args, options).command(options[:command]).invoke!
  32         rescue => e
  33           puts e
  34           puts "  #{e.backtrace.join("\n  ")}\n" if options[:backtrace]
  35           raise SystemExit
  36         end
  37
  38         protected
  39           # Override with your own script usage banner.
  40           def banner
  41             "Usage: #{$0} generator [options] [args]"
  42           end
  43
  44           def usage_message
  45             usage = "\nInstalled Generators\n"
  46             Rails::Generator::Base.sources.inject([]) do |mem, source|
  47               # Using an association list instead of a hash to preserve order,
  48               # for aesthetic reasons more than anything else.
  49               label = source.label.to_s.capitalize
  50               pair = mem.assoc(label)
  51               mem << (pair = [label, []]) if pair.nil?
  52               pair[1] |= source.names
  53               mem
  54             end.each do |label, names|
  55               usage << "  #{label}: #{names.join(', ')}\n" unless names.empty?
  56             end
  57
  58             usage << <<end_blurb
  59
  60 More are available at http://wiki.rubyonrails.org/rails/pages/AvailableGenerators
  61   1. Download, for example, login_generator.zip
  62   2. Unzip to directory #{Dir.user_home}/.rails/generators/login
  63      to use the generator with all your Rails apps
  64 end_blurb
  65
  66             if Object.const_defined?(:RAILS_ROOT)
  67               usage << <<end_blurb
  68      or to #{File.expand_path(RAILS_ROOT)}/lib/generators/login
  69      to use with this app only.
  70 end_blurb
  71             end
  72
  73             usage << <<end_blurb
  74   3. Run generate with no arguments for usage information
  75        #{$0} login
  76
  77 Generator gems are also available:
  78   1. gem search -r generator
  79   2. gem install login_generator
  80   3. #{$0} login
  81
  82 end_blurb
  83             return usage
  84           end
  85       end # Base
  86
  87     end
  88   end
  89 end