Class | Rails::Generator::Commands::Create |
In: |
vendor/rails/railties/lib/rails_generator/commands.rb
|
Parent: | Base |
Create is the premier generator command. It copies files, creates directories, renders templates, and more.
SYNONYM_LOOKUP_URI | = | "http://wordnet.princeton.edu/cgi-bin/webwn2.0?stage=2&word=%s&posnumber=1&searchtypenumber=2&senses=&showglosses=1" |
Check whether the given class names are already taken by Ruby or Rails. In the future, expand to check other namespaces such as the rest of the user‘s app.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 168 168: def class_collisions(*class_names) 169: class_names.flatten.each do |class_name| 170: # Convert to string to allow symbol arguments. 171: class_name = class_name.to_s 172: 173: # Skip empty strings. 174: next if class_name.strip.empty? 175: 176: # Split the class from its module nesting. 177: nesting = class_name.split('::') 178: name = nesting.pop 179: 180: # Extract the last Module in the nesting. 181: last = nesting.inject(Object) { |last, nest| 182: break unless last.const_defined?(nest) 183: last.const_get(nest) 184: } 185: 186: # If the last Module exists, check whether the given 187: # class exists and raise a collision if so. 188: if last and last.const_defined?(name.camelize) 189: raise_class_collision(class_name) 190: end 191: end 192: end
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 299 299: def complex_template(relative_source, relative_destination, template_options = {}) 300: options = template_options.dup 301: options[:assigns] ||= {} 302: options[:assigns]['template_for_inclusion'] = render_template_part(template_options) 303: template(relative_source, relative_destination, options) 304: end
Create a directory including any missing parent directories. Always directories which exist.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 308 308: def directory(relative_path) 309: path = destination_path(relative_path) 310: if File.exist?(path) 311: logger.exists relative_path 312: else 313: logger.create relative_path 314: unless options[:pretend] 315: FileUtils.mkdir_p(path) 316: 317: # Subversion doesn't do path adds, so we need to add 318: # each directory individually. 319: # So stack up the directory tree and add the paths to 320: # subversion in order without recursion. 321: if options[:svn] 322: stack=[relative_path] 323: until File.dirname(stack.last) == stack.last # dirname('.') == '.' 324: stack.push File.dirname(stack.last) 325: end 326: stack.reverse_each do |rel_path| 327: svn_path = destination_path(rel_path) 328: system("svn add -N #{svn_path}") unless File.directory?(File.join(svn_path, '.svn')) 329: end 330: end 331: end 332: end 333: end
Copy a file from source to destination with collision checking.
The file_options hash accepts :chmod and :shebang and :collision options. :chmod sets the permissions of the destination file:
file 'config/empty.log', 'log/test.log', :chmod => 0664
:shebang sets the #!/usr/bin/ruby line for scripts
file 'bin/generate.rb', 'script/generate', :chmod => 0755, :shebang => '/usr/bin/env ruby'
:collision sets the collision option only for the destination file:
file 'settings/server.yml', 'config/server.yml', :collision => :skip
Collisions are handled by checking whether the destination file exists and either skipping the file, forcing overwrite, or asking the user what to do.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 207 207: def file(relative_source, relative_destination, file_options = {}, &block) 208: # Determine full paths for source and destination files. 209: source = source_path(relative_source) 210: destination = destination_path(relative_destination) 211: destination_exists = File.exist?(destination) 212: 213: # If source and destination are identical then we're done. 214: if destination_exists and identical?(source, destination, &block) 215: return logger.identical(relative_destination) 216: end 217: 218: # Check for and resolve file collisions. 219: if destination_exists 220: 221: # Make a choice whether to overwrite the file. :force and 222: # :skip already have their mind made up, but give :ask a shot. 223: choice = case (file_options[:collision] || options[:collision]).to_sym #|| :ask 224: when :ask then force_file_collision?(relative_destination, source, destination, file_options, &block) 225: when :force then :force 226: when :skip then :skip 227: else raise "Invalid collision option: #{options[:collision].inspect}" 228: end 229: 230: # Take action based on our choice. Bail out if we chose to 231: # skip the file; otherwise, log our transgression and continue. 232: case choice 233: when :force then logger.force(relative_destination) 234: when :skip then return(logger.skip(relative_destination)) 235: else raise "Invalid collision choice: #{choice}.inspect" 236: end 237: 238: # File doesn't exist so log its unbesmirched creation. 239: else 240: logger.create relative_destination 241: end 242: 243: # If we're pretending, back off now. 244: return if options[:pretend] 245: 246: # Write destination file with optional shebang. Yield for content 247: # if block given so templaters may render the source file. If a 248: # shebang is requested, replace the existing shebang or insert a 249: # new one. 250: File.open(destination, 'wb') do |dest| 251: dest.write render_file(source, file_options, &block) 252: end 253: 254: # Optionally change permissions. 255: if file_options[:chmod] 256: FileUtils.chmod(file_options[:chmod], destination) 257: end 258: 259: # Optionally add file to subversion 260: system("svn add #{destination}") if options[:svn] 261: end
Checks if the source and the destination file are identical. If passed a block then the source file is a template that needs to first be evaluated before being compared to the destination.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 266 266: def identical?(source, destination, &block) 267: return false if File.directory? destination 268: source = block_given? ? File.open(source) {|sf| yield(sf)} : IO.read(source) 269: destination = IO.read(destination) 270: source == destination 271: end
When creating a migration, it knows to find the first available file in db/migrate and use the migration.rb template.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 344 344: def migration_template(relative_source, relative_destination, template_options = {}) 345: migration_directory relative_destination 346: migration_file_name = template_options[:migration_file_name] || file_name 347: raise "Another migration is already named #{migration_file_name}: #{existing_migrations(migration_file_name).first}" if migration_exists?(migration_file_name) 348: template(relative_source, "#{relative_destination}/#{next_migration_string}_#{migration_file_name}.rb", template_options) 349: end
Display a README.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 336 336: def readme(*relative_sources) 337: relative_sources.flatten.each do |relative_source| 338: logger.readme relative_source 339: puts File.read(source_path(relative_source)) unless options[:pretend] 340: end 341: end
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 351 351: def route_resources(*resources) 352: resource_list = resources.map { |r| r.to_sym.inspect }.join(', ') 353: sentinel = 'ActionController::Routing::Routes.draw do |map|' 354: 355: logger.route "map.resources #{resource_list}" 356: unless options[:pretend] 357: gsub_file 'config/routes.rb', /(#{Regexp.escape(sentinel)})/mi do |match| 358: "#{match}\n map.resources #{resource_list}\n" 359: end 360: end 361: end
Generate a file for a Rails application using an ERuby template. Looks up and evaluates a template by name and writes the result.
The ERB template uses explicit trim mode to best control the proliferation of whitespace in generated code. <%- trims leading whitespace; -%> trims trailing whitespace including one newline.
A hash of template options may be passed as the last argument. The options accepted by the file are accepted as well as :assigns, a hash of variable bindings. Example:
template 'foo', 'bar', :assigns => { :action => 'view' }
Template is implemented in terms of file. It calls file with a block which takes a file handle and returns its rendered contents.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 287 287: def template(relative_source, relative_destination, template_options = {}) 288: file(relative_source, relative_destination, template_options) do |file| 289: # Evaluate any assignments in a temporary, throwaway binding. 290: vars = template_options[:assigns] || {} 291: b = binding 292: vars.each { |k,v| eval "#{k} = vars[:#{k}] || vars['#{k}']", b } 293: 294: # Render the source file with the temporary binding. 295: ERB.new(file.read, nil, '-').result(b) 296: end 297: end