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.

Methods

Constants

SYNONYM_LOOKUP_URI = "http://wordnet.princeton.edu/perl/webwn?s=%s"

Public Instance methods

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.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 173
173:         def class_collisions(*class_names)
174:           path = class_names.shift
175:           class_names.flatten.each do |class_name|
176:             # Convert to string to allow symbol arguments.
177:             class_name = class_name.to_s
178: 
179:             # Skip empty strings.
180:             next if class_name.strip.empty?
181: 
182:             # Split the class from its module nesting.
183:             nesting = class_name.split('::')
184:             name = nesting.pop
185: 
186:             # Hack to limit const_defined? to non-inherited on 1.9.
187:             extra = []
188:             extra << false unless Object.method(:const_defined?).arity == 1
189: 
190:             # Extract the last Module in the nesting.
191:             last = nesting.inject(Object) { |last, nest|
192:               break unless last.const_defined?(nest, *extra)
193:               last.const_get(nest)
194:             }
195: 
196:             # If the last Module exists, check whether the given
197:             # class exists and raise a collision if so.
198:             if last and last.const_defined?(name.camelize, *extra)
199:               raise_class_collision(class_name)
200:             end
201:           end
202:         end

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 310
310:         def complex_template(relative_source, relative_destination, template_options = {})
311:           options = template_options.dup
312:           options[:assigns] ||= {}
313:           options[:assigns]['template_for_inclusion'] = render_template_part(template_options)
314:           template(relative_source, relative_destination, options)
315:         end

Create a directory including any missing parent directories. Always skips directories which exist.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 319
319:         def directory(relative_path)
320:           path = destination_path(relative_path)
321:           if File.exist?(path)
322:             logger.exists relative_path
323:           else
324:             logger.create relative_path
325:             unless options[:pretend]
326:               FileUtils.mkdir_p(path)
327:               # git doesn't require adding the paths, adding the files later will
328:               # automatically do a path add.
329: 
330:               # Subversion doesn't do path adds, so we need to add
331:               # each directory individually.
332:               # So stack up the directory tree and add the paths to
333:               # subversion in order without recursion.
334:               if options[:svn]
335:                 stack = [relative_path]
336:                 until File.dirname(stack.last) == stack.last # dirname('.') == '.'
337:                   stack.push File.dirname(stack.last)
338:                 end
339:                 stack.reverse_each do |rel_path|
340:                   svn_path = destination_path(rel_path)
341:                   system("svn add -N #{svn_path}") unless File.directory?(File.join(svn_path, '.svn'))
342:                 end
343:               end
344:             end
345:           end
346:         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.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 217
217:         def file(relative_source, relative_destination, file_options = {}, &block)
218:           # Determine full paths for source and destination files.
219:           source              = source_path(relative_source)
220:           destination         = destination_path(relative_destination)
221:           destination_exists  = File.exist?(destination)
222: 
223:           # If source and destination are identical then we're done.
224:           if destination_exists and identical?(source, destination, &block)
225:             return logger.identical(relative_destination)
226:           end
227: 
228:           # Check for and resolve file collisions.
229:           if destination_exists
230: 
231:             # Make a choice whether to overwrite the file.  :force and
232:             # :skip already have their mind made up, but give :ask a shot.
233:             choice = case (file_options[:collision] || options[:collision]).to_sym #|| :ask
234:               when :ask   then force_file_collision?(relative_destination, source, destination, file_options, &block)
235:               when :force then :force
236:               when :skip  then :skip
237:               else raise "Invalid collision option: #{options[:collision].inspect}"
238:             end
239: 
240:             # Take action based on our choice.  Bail out if we chose to
241:             # skip the file; otherwise, log our transgression and continue.
242:             case choice
243:               when :force then logger.force(relative_destination)
244:               when :skip  then return(logger.skip(relative_destination))
245:               else raise "Invalid collision choice: #{choice}.inspect"
246:             end
247: 
248:           # File doesn't exist so log its unbesmirched creation.
249:           else
250:             logger.create relative_destination
251:           end
252: 
253:           # If we're pretending, back off now.
254:           return if options[:pretend]
255: 
256:           # Write destination file with optional shebang.  Yield for content
257:           # if block given so templaters may render the source file.  If a
258:           # shebang is requested, replace the existing shebang or insert a
259:           # new one.
260:           File.open(destination, 'wb') do |dest|
261:             dest.write render_file(source, file_options, &block)
262:           end
263: 
264:           # Optionally change permissions.
265:           if file_options[:chmod]
266:             FileUtils.chmod(file_options[:chmod], destination)
267:           end
268: 
269:           # Optionally add file to subversion or git
270:           system("svn add #{destination}") if options[:svn]
271:           system("git add -v #{relative_destination}") if options[:git]
272:         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.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 277
277:         def identical?(source, destination, &block)
278:           return false if File.directory? destination
279:           source      = block_given? ? File.open(source) {|sf| yield(sf)} : IO.read(source)
280:           destination = IO.read(destination)
281:           source == destination
282:         end

When creating a migration, it knows to find the first available file in db/migrate and use the migration.rb template.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 357
357:         def migration_template(relative_source, relative_destination, template_options = {})
358:           migration_directory relative_destination
359:           migration_file_name = template_options[:migration_file_name] || file_name
360:           raise "Another migration is already named #{migration_file_name}: #{existing_migrations(migration_file_name).first}" if migration_exists?(migration_file_name)
361:           template(relative_source, "#{relative_destination}/#{next_migration_string}_#{migration_file_name}.rb", template_options)
362:         end

Display a README.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 349
349:         def readme(*relative_sources)
350:           relative_sources.flatten.each do |relative_source|
351:             logger.readme relative_source
352:             puts File.read(source_path(relative_source)) unless options[:pretend]
353:           end
354:         end

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 364
364:         def route_resources(*resources)
365:           resource_list = resources.map { |r| r.to_sym.inspect }.join(', ')
366:           sentinel = 'ActionController::Routing::Routes.draw do |map|'
367: 
368:           logger.route "map.resources #{resource_list}"
369:           unless options[:pretend]
370:             gsub_file 'config/routes.rb', /(#{Regexp.escape(sentinel)})/mi do |match|
371:               "#{match}\n  map.resources #{resource_list}\n"
372:             end
373:           end
374:         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.

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 298
298:         def template(relative_source, relative_destination, template_options = {})
299:           file(relative_source, relative_destination, template_options) do |file|
300:             # Evaluate any assignments in a temporary, throwaway binding.
301:             vars = template_options[:assigns] || {}
302:             b = template_options[:binding] || binding
303:             vars.each { |k,v| eval "#{k} = vars[:#{k}] || vars['#{k}']", b }
304: 
305:             # Render the source file with the temporary binding.
306:             ERB.new(file.read, nil, '-').result(b)
307:           end
308:         end

[Validate]