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/cgi-bin/webwn2.0?stage=2&word=%s&posnumber=1&searchtypenumber=2&senses=&showglosses=1"

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 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

[Source]

     # 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.

[Source]

     # 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.

[Source]

     # 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.

[Source]

     # 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.

[Source]

     # 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.

[Source]

     # 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

[Source]

     # 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.

[Source]

     # 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

[Validate]