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/perl/webwn?s=%s" |
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 157 157: def class_collisions(*class_names) 158: 159: # Initialize some check varibles 160: last_class = Object 161: current_class = nil 162: name = nil 163: 164: class_names.flatten.each do |class_name| 165: # Convert to string to allow symbol arguments. 166: class_name = class_name.to_s 167: 168: # Skip empty strings. 169: class_name.strip.empty? ? next : current_class = class_name 170: 171: # Split the class from its module nesting. 172: nesting = class_name.split('::') 173: name = nesting.pop 174: 175: # Extract the last Module in the nesting. 176: last = nesting.inject(last_class) { |last, nest| 177: break unless last_class.const_defined?(nest) 178: last_class = last_class.const_get(nest) 179: } 180: 181: end 182: # If the last Module exists, check whether the given 183: # class exists and raise a collision if so. 184: 185: if last_class and last_class.const_defined?(name.camelize) 186: raise_class_collision(current_class) 187: end 188: end
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 296 296: def complex_template(relative_source, relative_destination, template_options = {}) 297: options = template_options.dup 298: options[:assigns] ||= {} 299: options[:assigns]['template_for_inclusion'] = render_template_part(template_options) 300: template(relative_source, relative_destination, options) 301: end
Create a directory including any missing parent directories. Always skips directories which exist.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 305 305: def directory(relative_path) 306: path = destination_path(relative_path) 307: if File.exist?(path) 308: logger.exists relative_path 309: else 310: logger.create relative_path 311: unless options[:pretend] 312: FileUtils.mkdir_p(path) 313: # git doesn't require adding the paths, adding the files later will 314: # automatically do a path add. 315: 316: # Subversion doesn't do path adds, so we need to add 317: # each directory individually. 318: # So stack up the directory tree and add the paths to 319: # subversion in order without recursion. 320: if options[:svn] 321: stack = [relative_path] 322: until File.dirname(stack.last) == stack.last # dirname('.') == '.' 323: stack.push File.dirname(stack.last) 324: end 325: stack.reverse_each do |rel_path| 326: svn_path = destination_path(rel_path) 327: system("svn add -N #{svn_path}") unless File.directory?(File.join(svn_path, '.svn')) 328: end 329: end 330: end 331: end 332: 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 203 203: def file(relative_source, relative_destination, file_options = {}, &block) 204: # Determine full paths for source and destination files. 205: source = source_path(relative_source) 206: destination = destination_path(relative_destination) 207: destination_exists = File.exist?(destination) 208: 209: # If source and destination are identical then we're done. 210: if destination_exists and identical?(source, destination, &block) 211: return logger.identical(relative_destination) 212: end 213: 214: # Check for and resolve file collisions. 215: if destination_exists 216: 217: # Make a choice whether to overwrite the file. :force and 218: # :skip already have their mind made up, but give :ask a shot. 219: choice = case (file_options[:collision] || options[:collision]).to_sym #|| :ask 220: when :ask then force_file_collision?(relative_destination, source, destination, file_options, &block) 221: when :force then :force 222: when :skip then :skip 223: else raise "Invalid collision option: #{options[:collision].inspect}" 224: end 225: 226: # Take action based on our choice. Bail out if we chose to 227: # skip the file; otherwise, log our transgression and continue. 228: case choice 229: when :force then logger.force(relative_destination) 230: when :skip then return(logger.skip(relative_destination)) 231: else raise "Invalid collision choice: #{choice}.inspect" 232: end 233: 234: # File doesn't exist so log its unbesmirched creation. 235: else 236: logger.create relative_destination 237: end 238: 239: # If we're pretending, back off now. 240: return if options[:pretend] 241: 242: # Write destination file with optional shebang. Yield for content 243: # if block given so templaters may render the source file. If a 244: # shebang is requested, replace the existing shebang or insert a 245: # new one. 246: File.open(destination, 'wb') do |dest| 247: dest.write render_file(source, file_options, &block) 248: end 249: 250: # Optionally change permissions. 251: if file_options[:chmod] 252: FileUtils.chmod(file_options[:chmod], destination) 253: end 254: 255: # Optionally add file to subversion or git 256: system("svn add #{destination}") if options[:svn] 257: system("git add -v #{relative_destination}") if options[:git] 258: 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 263 263: def identical?(source, destination, &block) 264: return false if File.directory? destination 265: source = block_given? ? File.open(source) {|sf| yield(sf)} : IO.read(source) 266: destination = IO.read(destination) 267: source == destination 268: 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 343 343: def migration_template(relative_source, relative_destination, template_options = {}) 344: migration_directory relative_destination 345: migration_file_name = template_options[:migration_file_name] || file_name 346: raise "Another migration is already named #{migration_file_name}: #{existing_migrations(migration_file_name).first}" if migration_exists?(migration_file_name) 347: template(relative_source, "#{relative_destination}/#{next_migration_string}_#{migration_file_name}.rb", template_options) 348: end
Display a README.
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 335 335: def readme(*relative_sources) 336: relative_sources.flatten.each do |relative_source| 337: logger.readme relative_source 338: puts File.read(source_path(relative_source)) unless options[:pretend] 339: end 340: end
# File vendor/rails/railties/lib/rails_generator/commands.rb, line 350 350: def route_resources(*resources) 351: resource_list = resources.map { |r| r.to_sym.inspect }.join(', ') 352: sentinel = 'ActionController::Routing::Routes.draw do |map|' 353: 354: logger.route "map.resources #{resource_list}" 355: unless options[:pretend] 356: gsub_file 'config/routes.rb', /(#{Regexp.escape(sentinel)})/mi do |match| 357: "#{match}\n map.resources #{resource_list}\n" 358: end 359: end 360: 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 284 284: def template(relative_source, relative_destination, template_options = {}) 285: file(relative_source, relative_destination, template_options) do |file| 286: # Evaluate any assignments in a temporary, throwaway binding. 287: vars = template_options[:assigns] || {} 288: b = binding 289: vars.each { |k,v| eval "#{k} = vars[:#{k}] || vars['#{k}']", b } 290: 291: # Render the source file with the temporary binding. 292: ERB.new(file.read, nil, '-').result(b) 293: end 294: end