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 172
172:         def class_collisions(*class_names)
173: 
174:           # Initialize some check varibles
175:           last_class = Object
176:           current_class = nil
177:           name = nil
178: 
179:           class_names.flatten.each do |class_name|
180:             # Convert to string to allow symbol arguments.
181:             class_name = class_name.to_s
182: 
183:             # Skip empty strings.
184:             class_name.strip.empty? ? next : current_class = class_name
185: 
186:             # Split the class from its module nesting.
187:             nesting = class_name.split('::')
188:             name = nesting.pop
189: 
190:             # Extract the last Module in the nesting.
191:             last = nesting.inject(last_class) { |last, nest|
192:               break unless last_class.const_defined?(nest)
193:               last_class = last_class.const_get(nest)
194:             }
195: 
196:           end
197:           # If the last Module exists, check whether the given
198:           # class exists and raise a collision if so.
199: 
200:           if last_class and last_class.const_defined?(name.camelize)
201:             raise_class_collision(current_class)
202:           end
203:         end

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 311
311:         def complex_template(relative_source, relative_destination, template_options = {})
312:           options = template_options.dup
313:           options[:assigns] ||= {}
314:           options[:assigns]['template_for_inclusion'] = render_template_part(template_options)
315:           template(relative_source, relative_destination, options)
316:         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 320
320:         def directory(relative_path)
321:           path = destination_path(relative_path)
322:           if File.exist?(path)
323:             logger.exists relative_path
324:           else
325:             logger.create relative_path
326:             unless options[:pretend]
327:               FileUtils.mkdir_p(path)
328:               # git doesn't require adding the paths, adding the files later will
329:               # automatically do a path add.
330: 
331:               # Subversion doesn't do path adds, so we need to add
332:               # each directory individually.
333:               # So stack up the directory tree and add the paths to
334:               # subversion in order without recursion.
335:               if options[:svn]
336:                 stack = [relative_path]
337:                 until File.dirname(stack.last) == stack.last # dirname('.') == '.'
338:                   stack.push File.dirname(stack.last)
339:                 end
340:                 stack.reverse_each do |rel_path|
341:                   svn_path = destination_path(rel_path)
342:                   system("svn add -N #{svn_path}") unless File.directory?(File.join(svn_path, '.svn'))
343:                 end
344:               end
345:             end
346:           end
347:         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 218
218:         def file(relative_source, relative_destination, file_options = {}, &block)
219:           # Determine full paths for source and destination files.
220:           source              = source_path(relative_source)
221:           destination         = destination_path(relative_destination)
222:           destination_exists  = File.exist?(destination)
223: 
224:           # If source and destination are identical then we're done.
225:           if destination_exists and identical?(source, destination, &block)
226:             return logger.identical(relative_destination)
227:           end
228: 
229:           # Check for and resolve file collisions.
230:           if destination_exists
231: 
232:             # Make a choice whether to overwrite the file.  :force and
233:             # :skip already have their mind made up, but give :ask a shot.
234:             choice = case (file_options[:collision] || options[:collision]).to_sym #|| :ask
235:               when :ask   then force_file_collision?(relative_destination, source, destination, file_options, &block)
236:               when :force then :force
237:               when :skip  then :skip
238:               else raise "Invalid collision option: #{options[:collision].inspect}"
239:             end
240: 
241:             # Take action based on our choice.  Bail out if we chose to
242:             # skip the file; otherwise, log our transgression and continue.
243:             case choice
244:               when :force then logger.force(relative_destination)
245:               when :skip  then return(logger.skip(relative_destination))
246:               else raise "Invalid collision choice: #{choice}.inspect"
247:             end
248: 
249:           # File doesn't exist so log its unbesmirched creation.
250:           else
251:             logger.create relative_destination
252:           end
253: 
254:           # If we're pretending, back off now.
255:           return if options[:pretend]
256: 
257:           # Write destination file with optional shebang.  Yield for content
258:           # if block given so templaters may render the source file.  If a
259:           # shebang is requested, replace the existing shebang or insert a
260:           # new one.
261:           File.open(destination, 'wb') do |dest|
262:             dest.write render_file(source, file_options, &block)
263:           end
264: 
265:           # Optionally change permissions.
266:           if file_options[:chmod]
267:             FileUtils.chmod(file_options[:chmod], destination)
268:           end
269: 
270:           # Optionally add file to subversion or git
271:           system("svn add #{destination}") if options[:svn]
272:           system("git add -v #{relative_destination}") if options[:git]
273:         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 278
278:         def identical?(source, destination, &block)
279:           return false if File.directory? destination
280:           source      = block_given? ? File.open(source) {|sf| yield(sf)} : IO.read(source)
281:           destination = IO.read(destination)
282:           source == destination
283:         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 358
358:         def migration_template(relative_source, relative_destination, template_options = {})
359:           migration_directory relative_destination
360:           migration_file_name = template_options[:migration_file_name] || file_name
361:           raise "Another migration is already named #{migration_file_name}: #{existing_migrations(migration_file_name).first}" if migration_exists?(migration_file_name)
362:           template(relative_source, "#{relative_destination}/#{next_migration_string}_#{migration_file_name}.rb", template_options)
363:         end

Display a README.

[Source]

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

[Source]

     # File vendor/rails/railties/lib/rails_generator/commands.rb, line 365
365:         def route_resources(*resources)
366:           resource_list = resources.map { |r| r.to_sym.inspect }.join(', ')
367:           sentinel = 'ActionController::Routing::Routes.draw do |map|'
368: 
369:           logger.route "map.resources #{resource_list}"
370:           unless options[:pretend]
371:             gsub_file 'config/routes.rb', /(#{Regexp.escape(sentinel)})/mi do |match|
372:               "#{match}\n  map.resources #{resource_list}\n"
373:             end
374:           end
375:         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 299
299:         def template(relative_source, relative_destination, template_options = {})
300:           file(relative_source, relative_destination, template_options) do |file|
301:             # Evaluate any assignments in a temporary, throwaway binding.
302:             vars = template_options[:assigns] || {}
303:             b = binding
304:             vars.each { |k,v| eval "#{k} = vars[:#{k}] || vars['#{k}']", b }
305: 
306:             # Render the source file with the temporary binding.
307:             ERB.new(file.read, nil, '-').result(b)
308:           end
309:         end

[Validate]