aboutsummaryrefslogtreecommitdiffstats
path: root/railties/lib/initializer.rb
blob: 9035138779d57142c3f61987fa9f7c76f8c39e91 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
require 'logger'

RAILS_ENV = (ENV['RAILS_ENV'] || 'development').dup unless defined?(RAILS_ENV)

module Rails
  # The Initializer is responsible for processing the Rails configuration, such
  # as setting the $LOAD_PATH, requiring the right frameworks, initializing
  # logging, and more. It can be run either as a single command that'll just
  # use the default configuration, like this:
  #
  #   Rails::Initializer.run
  #
  # But normally it's more interesting to pass in a custom configuration
  # through the block running:
  #
  #   Rails::Initializer.run do |config|
  #     config.frameworks -= [ :action_web_service ]
  #   end
  #
  # This will use the default configuration options from Rails::Configuration,
  # but allow for overwriting on select areas.
  class Initializer
    # The Configuration instance used by this Initializer instance.
    attr_reader :configuration
    
    # Runs the initializer. By default, this will invoke the #process method,
    # which simply executes all of the initialization routines. Alternately,
    # you can specify explicitly which initialization routine you want:
    #
    #   Rails::Initializer.run(:set_load_path)
    #
    # This is useful if you only want the load path initialized, without
    # incuring the overhead of completely loading the entire environment. 
    def self.run(command = :process, configuration = Configuration.new)
      yield configuration if block_given?
      new(configuration).send(command)
    end
    
    # Create a new Initializer instance that references the given Configuration
    # instance.
    def initialize(configuration)
      @configuration = configuration
    end
    
    # Sequentially step through all of the available initialization routines,
    # in order:
    #
    # * #set_load_path
    # * #set_connection_adapters
    # * #require_frameworks
    # * #load_environment
    # * #initialize_database
    # * #initialize_logger
    # * #initialize_framework_logging
    # * #initialize_framework_views
    # * #initialize_routing
    # * #initialize_dependency_mechanism
    # * #initialize_breakpoints
    # * #initialize_whiny_nils
    # * #initialize_framework_settings
    # * #load_environment
    # * #load_plugins
    #
    # (Note that #load_environment is invoked twice, once at the start and
    # once at the end, to support the legacy configuration style where the
    # environment could overwrite the defaults directly, instead of via the
    # Configuration instance. 
    def process
      set_load_path
      set_connection_adapters

      require_frameworks
      load_environment

      initialize_database
      initialize_logger
      initialize_framework_logging
      initialize_framework_views
      initialize_routing
      initialize_dependency_mechanism
      initialize_breakpoints
      initialize_whiny_nils
      
      initialize_framework_settings
      
      # Support for legacy configuration style where the environment
      # could overwrite anything set from the defaults/global through
      # the individual base class configurations.
      load_environment
      
      load_framework_info

      load_plugins
    end
    
    # Set the <tt>$LOAD_PATH</tt> based on the value of
    # Configuration#load_paths. Duplicates are removed.
    def set_load_path
      configuration.load_paths.reverse.each { |dir| $LOAD_PATH.unshift(dir) if File.directory?(dir) }
      $LOAD_PATH.uniq!
    end
    
    # Sets the +RAILS_CONNECTION_ADAPTERS+ constant based on the value of
    # Configuration#connection_adapters. This constant is used to determine
    # which database adapters should be loaded (by default, all adapters are
    # loaded).
    def set_connection_adapters
      Object.const_set("RAILS_CONNECTION_ADAPTERS", configuration.connection_adapters) if configuration.connection_adapters
    end
    
    # Requires all frameworks specified by the Configuration#frameworks
    # list. By default, all frameworks (ActiveRecord, ActiveSupport,
    # ActionPack, ActionMailer, and ActionWebService) are loaded.
    def require_frameworks
      configuration.frameworks.each { |framework| require(framework.to_s) }
    end
    
    # Loads Rails::Version and Rails::Info.
    # TODO: Make this work via dependencies.rb/const_missing instead.
    def load_framework_info
      require 'rails_info'
    end
    
    # Loads all plugins in the <tt>vendor/plugins</tt> directory. Each
    # subdirectory of <tt>vendor/plugins</tt> is inspected as follows:
    #
    # * if the directory has a +lib+ subdirectory, add it to the load path
    # * if the directory contains an <tt>init.rb</tt> file, read it in and
    #   eval it.
    #
    # After all plugins are loaded, duplicates are removed from the load path.
    def load_plugins
      config = configuration

      Dir.glob("#{configuration.plugins_path}/*") do |directory|
        next if File.basename(directory)[0] == ?. || !File.directory?(directory)

        if File.directory?("#{directory}/lib")
          $LOAD_PATH.unshift "#{directory}/lib"
        end

        if File.exist?("#{directory}/init.rb")
          silence_warnings do
            eval(IO.read("#{directory}/init.rb"), binding)
          end
        end
      end

      $LOAD_PATH.uniq!
    end

    # Loads the environment specified by Configuration#environment_path, which
    # is typically one of development, testing, or production.
    def load_environment
      silence_warnings do
        config = configuration
        constants = self.class.constants
        eval(IO.read(configuration.environment_path), binding)
        (self.class.constants - constants).each do |const|
          Object.const_set(const, self.class.const_get(const))
        end
      end
    end
    
    # This initialization routine does nothing unless <tt>:active_record</tt>
    # is one of the frameworks to load (Configuration#frameworks). If it is,
    # this sets the database configuration from Configuration#database_configuration
    # and then establishes the connection.
    def initialize_database
      return unless configuration.frameworks.include?(:active_record)
      ActiveRecord::Base.configurations = configuration.database_configuration
      ActiveRecord::Base.establish_connection
    end
    
    # If the +RAILS_DEFAULT_LOGGER+ constant is already set, this initialization
    # routine does nothing. If the constant is not set, and Configuration#logger
    # is not +nil+, this also does nothing. Otherwise, a new logger instance
    # is created at Configuration#log_path, with a default log level of
    # Configuration#log_level.
    #
    # If the log could not be created, the log will be set to output to
    # +STDERR+, with a log level of +WARN+.
    def initialize_logger
      # if the environment has explicitly defined a logger, use it
      return if defined?(RAILS_DEFAULT_LOGGER)

      unless logger = configuration.logger
        begin
          logger = Logger.new(configuration.log_path)
          logger.level = Logger.const_get(configuration.log_level.to_s.upcase)
        rescue StandardError
          logger = Logger.new(STDERR)
          logger.level = Logger::WARN
          logger.warn(
            "Rails Error: Unable to access log file. Please ensure that #{configuration.log_path} exists and is chmod 0666. " +
            "The log level has been raised to WARN and the output directed to STDERR until the problem is fixed."
          )
        end
      end
      
      silence_warnings { Object.const_set "RAILS_DEFAULT_LOGGER", logger }
    end
    
    # Sets the logger for ActiveRecord, ActionController, and ActionMailer
    # (but only for those frameworks that are to be loaded). If the framework's
    # logger is already set, it is not changed, otherwise it is set to use
    # +RAILS_DEFAULT_LOGGER+.
    def initialize_framework_logging
      for framework in ([ :active_record, :action_controller, :action_mailer ] & configuration.frameworks)
        framework.to_s.camelize.constantize.const_get("Base").logger ||= RAILS_DEFAULT_LOGGER
      end
    end
    
    # Sets the +template_root+ for ActionController::Base and ActionMailer::Base
    # (but only for those frameworks that are to be loaded). If the framework's
    # +template_root+ has already been set, it is not changed, otherwise it is
    # set to use Configuration#view_path.
    def initialize_framework_views
      for framework in ([ :action_controller, :action_mailer ] & configuration.frameworks)
        framework.to_s.camelize.constantize.const_get("Base").template_root ||= configuration.view_path
      end
    end

    # If ActionController is not one of the loaded frameworks (Configuration#frameworks)
    # this does nothing. Otherwise, it loads the routing definitions and sets up
    # loading module used to lazily load controllers (Configuration#controller_paths).
    def initialize_routing
      return unless configuration.frameworks.include?(:action_controller)
      ActionController::Routing::Routes.reload
      Object.const_set "Controllers", Dependencies::LoadingModule.root(*configuration.controller_paths)
    end
    
    # Sets the dependency loading mechanism based on the value of
    # Configuration#cache_classes.
    def initialize_dependency_mechanism
      Dependencies.mechanism = configuration.cache_classes ? :require : :load
    end
    
    # Sets the +BREAKPOINT_SERVER_PORT+ if Configuration#breakpoint_server
    # is true.
    def initialize_breakpoints
      silence_warnings { Object.const_set("BREAKPOINT_SERVER_PORT", 42531) if configuration.breakpoint_server }
    end

    # Loads support for "whiny nil" (noisy warnings when methods are invoked
    # on +nil+ values) if Configuration#whiny_nils is true.
    def initialize_whiny_nils
      require('active_support/whiny_nil') if configuration.whiny_nils
    end

    # Initialize framework-specific settings for each of the loaded frameworks
    # (Configuration#frameworks). The available settings map to the accessors
    # on each of the corresponding Base classes.
    def initialize_framework_settings
      configuration.frameworks.each do |framework|
        base_class = framework.to_s.camelize.constantize.const_get("Base")

        configuration.send(framework).each do |setting, value|
          base_class.send("#{setting}=", value)
        end
      end
    end
  end
  
  # The Configuration class holds all the parameters for the Initializer and
  # ships with defaults that suites most Rails applications. But it's possible
  # to overwrite everything. Usually, you'll create an Configuration file
  # implicitly through the block running on the Initializer, but it's also
  # possible to create the Configuration instance in advance and pass it in
  # like this:
  #
  #   config = Rails::Configuration.new
  #   Rails::Initializer.run(:process, config)
  class Configuration
    # A stub for setting options on ActionController::Base
    attr_accessor :action_controller
    
    # A stub for setting options on ActionMailer::Base
    attr_accessor :action_mailer
    
    # A stub for setting options on ActionView::Base
    attr_accessor :action_view
    
    # A stub for setting options on ActionWebService::Base
    attr_accessor :action_web_service
    
    # A stub for setting options on ActiveRecord::Base
    attr_accessor :active_record
    
    # Whether or not to use the breakpoint server (boolean)
    attr_accessor :breakpoint_server
    
    # Whether or not classes should be cached (set to false if you want
    # application classes to be reloaded on each request)
    attr_accessor :cache_classes
    
    # The list of connection adapters to load. (By default, all connection
    # adapters are loaded. You can set this to be just the adapter(s) you
    # will use to reduce your application's load time.)
    attr_accessor :connection_adapters
    
    # The list of paths that should be searched for controllers. (Defaults
    # to <tt>app/controllers</tt> and <tt>components</tt>.)
    attr_accessor :controller_paths

    # The path to the database configuration file to use. (Defaults to
    # <tt>config/database.yml</tt>.)
    attr_accessor :database_configuration_file
    
    # The list of rails framework components that should be loaded. (Defaults
    # to <tt>:active_record</tt>, <tt>:action_controller</tt>,
    # <tt>:action_view</tt>, <tt>:action_mailer</tt>, and
    # <tt>:action_web_service</tt>).
    attr_accessor :frameworks
    
    # An array of additional paths to prepend to the load path. By default,
    # all +app+, +lib+, +vendor+ and mock paths are included in this list.
    attr_accessor :load_paths
    
    # The log level to use for the default Rails logger. In production mode,
    # this defaults to <tt>:info</tt>. In development mode, it defaults to
    # <tt>:debug</tt>.
    attr_accessor :log_level
    
    # The path to the log file to use. Defaults to log/#{environment}.log
    # (e.g. log/development.log or log/production.log).
    attr_accessor :log_path
    
    # The specific logger to use. By default, a logger will be created and
    # initialized using #log_path and #log_level, but a programmer may
    # specifically set the logger to use via this accessor and it will be
    # used directly.
    attr_accessor :logger
    
    # The root of the application's views. (Defaults to <tt>app/views</tt>.)
    attr_accessor :view_path
    
    # Set to +true+ if you want to be warned (noisily) when you try to invoke
    # any method of +nil+. Set to +false+ for the standard Ruby behavior.
    attr_accessor :whiny_nils
    
    # Create a new Configuration instance, initialized with the default
    # values.
    def initialize
      self.frameworks                   = default_frameworks
      self.load_paths                   = default_load_paths
      self.log_path                     = default_log_path
      self.log_level                    = default_log_level
      self.view_path                    = default_view_path
      self.controller_paths             = default_controller_paths
      self.cache_classes                = default_cache_classes
      self.breakpoint_server            = default_breakpoint_server
      self.whiny_nils                   = default_whiny_nils
      self.database_configuration_file  = default_database_configuration_file
      
      for framework in default_frameworks
        self.send("#{framework}=", OrderedOptions.new)
      end
    end
    
    # Loads and returns the contents of the #database_configuration_file. The
    # contents of the file are processed via ERB before being sent through
    # YAML::load.
    def database_configuration
      YAML::load(ERB.new(IO.read(database_configuration_file)).result)
    end
    
    # The path to the current environment's file (development.rb, etc.). By
    # default the file is at <tt>config/environments/#{environment}.rb</tt>.
    def environment_path
      "#{RAILS_ROOT}/config/environments/#{environment}.rb"
    end

    # The path to the root of the plugins directory. By default, it is in
    # <tt>vendor/plugins</tt>.
    def plugins_path
      "#{RAILS_ROOT}/vendor/plugins"
    end
    
    # Return the currently selected environment. By default, it returns the
    # value of the +RAILS_ENV+ constant.
    def environment
      ::RAILS_ENV
    end

    private
      def default_frameworks
        [ :active_record, :action_controller, :action_view, :action_mailer, :action_web_service ]
      end
    
      def default_load_paths
        paths = ["#{RAILS_ROOT}/test/mocks/#{environment}"]

        # Then model subdirectories.
        # TODO: Don't include .rb models as load paths
        paths.concat(Dir["#{RAILS_ROOT}/app/models/[_a-z]*"])
        paths.concat(Dir["#{RAILS_ROOT}/components/[_a-z]*"])

        # Followed by the standard includes.
        # TODO: Don't include dirs for frameworks that are not used
        paths.concat %w(
          app 
          app/models 
          app/controllers
          app/helpers
          app/services
          app/apis 
          components 
          config 
          lib 
          vendor 
          vendor/rails/railties
          vendor/rails/railties/lib
          vendor/rails/actionpack/lib
          vendor/rails/activesupport/lib
          vendor/rails/activerecord/lib
          vendor/rails/actionmailer/lib
          vendor/rails/actionwebservice/lib
        ).map { |dir| "#{RAILS_ROOT}/#{dir}" }.select { |dir| File.directory?(dir) }
      end

      def default_log_path
        File.join(RAILS_ROOT, 'log', "#{environment}.log")
      end
      
      def default_log_level
        environment == 'production' ? :info : :debug
      end
      
      def default_database_configuration_file
        File.join(RAILS_ROOT, 'config', 'database.yml')
      end
      
      def default_view_path
        File.join(RAILS_ROOT, 'app', 'views')
      end
      
      def default_controller_paths
        [ File.join(RAILS_ROOT, 'app', 'controllers'), File.join(RAILS_ROOT, 'components') ]
      end
      
      def default_dependency_mechanism
        :load
      end
      
      def default_cache_classes
        false
      end
      
      def default_breakpoint_server
        false
      end
      
      def default_whiny_nils
        false
      end
  end
end

# Needs to be duplicated from Active Support since its needed before Active
# Support is available.
class OrderedOptions < Array # :nodoc:
  def []=(key, value)
    key = key.to_sym

    if pair = find_pair(key)
      pair.pop
      pair << value
    else
      self << [key, value]
    end
  end

  def [](key)
    pair = find_pair(key.to_sym)
    pair ? pair.last : nil
  end

  def method_missing(name, *args)
    if name.to_s =~ /(.*)=$/
      self[$1.to_sym] = args.first
    else
      self[name]
    end
  end

  private
    def find_pair(key)
      self.each { |i| return i if i.first == key }
      return false
    end
end