aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/lib/active_record/fixtures.rb
blob: dab719946ffcf0d3d80dbdc000d34ed684533c5b (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
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
require 'erb'
require 'yaml'
require 'csv'

# Fixtures are a way of organizing data that you want to test against; in short, sample data. They come in 3 flavours:
#
#   1.  YAML fixtures
#   2.  CSV fixtures
#   3.  Single-file fixtures
#
# = YAML fixtures
#
# This type of fixture is in YAML format and the preferred default. YAML is a file format which describes data structures
# in a non-verbose, humanly-readable format. It ships with Ruby 1.8.1+.
#
# Unlike single-file fixtures, YAML fixtures are stored in a single file per model, which is place in the directory appointed
# by <tt>Test::Unit::TestCase.fixture_path=(path)</tt> (this is automatically configured for Rails, so you can just
# put your files in <your-rails-app>/test/fixtures/). The fixture file ends with the .yml file extension (Rails example:
# "<your-rails-app>/test/fixtures/web_sites.yml"). The format of a YAML fixture file looks like this:
#
#   rubyonrails:
#     id: 1
#     name: Ruby on Rails
#     url: http://www.rubyonrails.org
#
#   google:
#     id: 2
#     name: Google
#     url: http://www.google.com
#
# This YAML fixture file includes two fixtures.  Each YAML fixture (ie. record) is given a name and is followed by an
# indented list of key/value pairs in the "key: value" format.  Records are separated by a blank line for your viewing
# pleasure.
#
# = CSV fixtures
#
# Fixtures can also be kept in the Comma Separated Value format. Akin to YAML fixtures, CSV fixtures are stored
# in a single file, but, instead end with the .csv file extension (Rails example: "<your-rails-app>/test/fixtures/web_sites.csv")
#
# The format of this type of fixture file is much more compact than the others, but also a little harder to read by us
# humans.  The first line of the CSV file is a comma-separated list of field names.  The rest of the file is then comprised
# of the actual data (1 per line).  Here's an example:
#
#   id, name, url
#   1, Ruby On Rails, http://www.rubyonrails.org
#   2, Google, http://www.google.com
#
# Should you have a piece of data with a comma character in it, you can place double quotes around that value.  If you
# need to use a double quote character, you must escape it with another double quote.
#
# Another unique attribute of the CSV fixture is that it has *no* fixture name like the other two formats.  Instead, the
# fixture names are automatically generated by deriving the class name of the fixture file and adding an incrementing
# number to the end.  In our example, the 1st fixture would be called "web_site_1" and the 2nd one would be called
# "web_site_2".
#
# Most databases and spreadsheets support exporting to CSV format, so this is a great format for you to choose if you
# have existing data somewhere already.
#
# = Single-file fixtures
#
# This type of fixtures was the original format for Active Record that has since been deprecated in favor of the YAML and CSV formats.
# Fixtures for this format are created by placing text files in a sub-directory (with the name of the model) to the directory
# appointed by <tt>Test::Unit::TestCase.fixture_path=(path)</tt> (this is automatically configured for Rails, so you can just
# put your files in <your-rails-app>/test/fixtures/<your-model-name>/ -- like <your-rails-app>/test/fixtures/web_sites/ for the WebSite
# model).
#
# Each text file placed in this directory represents a "record".  Usually these types of fixtures are named without
# extensions, but if you are on a Windows machine, you might consider adding .txt as the extension.  Here's what the
# above example might look like:
#
#   web_sites/google
#   web_sites/yahoo.txt
#   web_sites/ruby-on-rails
#
# The file format of a standard fixture is simple.  Each line is a property (or column in db speak) and has the syntax
# of "name => value".  Here's an example of the ruby-on-rails fixture above:
#
#   id => 1
#   name => Ruby on Rails
#   url => http://www.rubyonrails.org
#
# = Using Fixtures
#
# Since fixtures are a testing construct, we use them in our unit and functional tests.  There are two ways to use the
# fixtures, but first lets take a look at a sample unit test found:
#
#   require 'web_site'
#
#   class WebSiteTest < Test::Unit::TestCase
#     def test_web_site_count
#       assert_equal 2, WebSite.count
#     end
#   end
#
# As it stands, unless we pre-load the web_site table in our database with two records, this test will fail.  Here's the
# easiest way to add fixtures to the database:
#
#   ...
#   class WebSiteTest < Test::Unit::TestCase
#     fixtures :web_sites # add more by separating the symbols with commas
#   ...
#
# By adding a "fixtures" method to the test case and passing it a list of symbols (only one is shown here tho), we trigger
# the testing environment to automatically load the appropriate fixtures into the database before each test.  
# To ensure consistent data, the environment deletes the fixtures before running the load.
#
# In addition to being available in the database, the fixtures are also loaded into a hash stored in an instance variable
# of the test case.  It is named after the symbol... so, in our example, there would be a hash available called
# @web_sites.  This is where the "fixture name" comes into play.
#
# On top of that, each record is automatically "found" (using Model.find(id)) and placed in the instance variable of its name.
# So for the YAML fixtures, we'd get @rubyonrails and @google, which could be interrogated using regular Active Record semantics:
#
#   # test if the object created from the fixture data has the same attributes as the data itself
#   def test_find
#     assert_equal @web_sites["rubyonrails"]["name"], @rubyonrails.name
#   end
#
# As seen above, the data hash created from the YAML fixtures would have @web_sites["rubyonrails"]["url"] return
# "http://www.rubyonrails.org" and @web_sites["google"]["name"] would return "Google". The same fixtures, but loaded
# from a CSV fixture file would be accessible via @web_sites["web_site_1"]["name"] == "Ruby on Rails" and have the individual
# fixtures available as instance variables @web_site_1 and @web_site_2.
#
# If you do not wish to use instantiated fixtures (usually for performance reasons) there are two options.
#
#   - to completely disable instantiated fixtures:
#       self.use_instantiated_fixtures = false
#
#   - to keep the fixture instance (@web_sites) available, but do not automatically 'find' each instance:
#       self.use_instantiated_fixtures = :no_instances 
#
# Even if auto-instantiated fixtures are disabled, you can still access them
# by name via special dynamic methods. Each method has the same name as the
# model, and accepts the name of the fixture to instantiate:
#
#   fixtures :web_sites
#
#   def test_find
#     assert_equal "Ruby on Rails", web_sites(:rubyonrails).name
#   end
#
# = Dynamic fixtures with ERb
#
# Some times you don't care about the content of the fixtures as much as you care about the volume. In these cases, you can
# mix ERb in with your YAML or CSV fixtures to create a bunch of fixtures for load testing, like:
#
# <% for i in 1..1000 %>
# fix_<%= i %>:
#   id: <%= i %>
#   name: guy_<%= 1 %>
# <% end %>
#
# This will create 1000 very simple YAML fixtures.
#
# Using ERb, you can also inject dynamic values into your fixtures with inserts like <%= Date.today.strftime("%Y-%m-%d") %>.
# This is however a feature to be used with some caution. The point of fixtures are that they're stable units of predictable
# sample data. If you feel that you need to inject dynamic values, then perhaps you should reexamine whether your application
# is properly testable. Hence, dynamic values in fixtures are to be considered a code smell.
#
# = Transactional fixtures
#
# TestCases can use begin+rollback to isolate their changes to the database instead of having to delete+insert for every test case. 
# They can also turn off auto-instantiation of fixture data since the feature is costly and often unused.
#
#   class FooTest < Test::Unit::TestCase
#     self.use_transactional_fixtures = true
#     self.use_instantiated_fixtures = false
#   
#     fixtures :foos
#   
#     def test_godzilla
#       assert !Foo.find(:all).empty?
#       Foo.destroy_all
#       assert Foo.find(:all).empty?
#     end
#   
#     def test_godzilla_aftermath
#       assert !Foo.find(:all).empty?
#     end
#   end
#   
# If you preload your test database with all fixture data (probably in the Rakefile task) and use transactional fixtures, 
# then you may omit all fixtures declarations in your test cases since all the data's already there and every case rolls back its changes.
#
# In order to use instantiated fixtures with preloaded data, set +self.pre_loaded_fixtures+ to true. This will provide 
# access to fixture data for every table that has been loaded through fixtures (depending on the value of +use_instantiated_fixtures+)
#
# When *not* to use transactional fixtures: 
#   1. You're testing whether a transaction works correctly. Nested transactions don't commit until all parent transactions commit, 
#      particularly, the fixtures transaction which is begun in setup and rolled back in teardown. Thus, you won't be able to verify 
#      the results of your transaction until Active Record supports nested transactions or savepoints (in progress.) 
#   2. Your database does not support transactions. Every Active Record database supports transactions except MySQL MyISAM. 
#      Use InnoDB, MaxDB, or NDB instead.
class Fixtures < Hash
  DEFAULT_FILTER_RE = /\.ya?ml$/

  def self.instantiate_fixtures(object, table_name, fixtures, load_instances=true)
    old_logger_level = ActiveRecord::Base.logger.level
    ActiveRecord::Base.logger.level = Logger::ERROR

    object.instance_variable_set "@#{table_name.to_s.gsub('.','_')}", fixtures
    if load_instances
      fixtures.each do |name, fixture|
        if model = fixture.find
          object.instance_variable_set "@#{name}", model
        end
      end
    end

    ActiveRecord::Base.logger.level = old_logger_level
  end
  
  def self.instantiate_all_loaded_fixtures(object, load_instances=true)
    all_loaded_fixtures.each do |table_name, fixtures|
      Fixtures.instantiate_fixtures(object, table_name, fixtures, load_instances)
    end
  end
  
  cattr_accessor :all_loaded_fixtures
  self.all_loaded_fixtures = {}

  def self.create_fixtures(fixtures_directory, *table_names)
    connection = block_given? ? yield : ActiveRecord::Base.connection
    old_logger_level = ActiveRecord::Base.logger.level

    begin
      ActiveRecord::Base.logger.level = Logger::ERROR

      fixtures_map = {}
      fixtures = table_names.flatten.map do |table_name|
        fixtures_map[table_name] = Fixtures.new(connection, File.split(table_name.to_s).last, File.join(fixtures_directory, table_name.to_s))
      end               
      all_loaded_fixtures.merge! fixtures_map  
      
      connection.transaction do
        fixtures.reverse.each { |fixture| fixture.delete_existing_fixtures }
        fixtures.each { |fixture| fixture.insert_fixtures }
      end
      
      reset_sequences(connection, table_names) if connection.is_a?(ActiveRecord::ConnectionAdapters::PostgreSQLAdapter)

      return fixtures.size > 1 ? fixtures : fixtures.first
    ensure
      ActiveRecord::Base.logger.level = old_logger_level
    end
  end

  # Work around for PostgreSQL to have new fixtures created from id 1 and running.
  def self.reset_sequences(connection, table_names)
    table_names.flatten.each do |table|
      table_class = Inflector.classify(table.to_s)
      if Object.const_defined?(table_class)
        pk = eval("#{table_class}::primary_key")
        if pk == 'id'
          connection.execute(
            "SELECT setval('#{table.to_s}_id_seq', (SELECT MAX(id) FROM #{table.to_s}), true)", 
            'Setting Sequence'
          )
        end
      end
    end
  end

  attr_reader :table_name

  def initialize(connection, table_name, fixture_path, file_filter = DEFAULT_FILTER_RE)
    @connection, @table_name, @fixture_path, @file_filter = connection, table_name, fixture_path, file_filter
    @class_name = Inflector.classify(@table_name)

    read_fixture_files
  end

  def delete_existing_fixtures
    @connection.delete "DELETE FROM #{@table_name}", 'Fixture Delete'
  end

  def insert_fixtures
    values.each do |fixture|
      @connection.execute "INSERT INTO #{@table_name} (#{fixture.key_list}) VALUES (#{fixture.value_list})", 'Fixture Insert'
    end
  end

  private
    def read_fixture_files
      if File.file?(yaml_file_path)
        # YAML fixtures
        begin
          yaml = YAML::load(erb_render(IO.read(yaml_file_path)))
          yaml.each { |name, data| self[name] = Fixture.new(data, @class_name) } if yaml
        rescue Exception=>boom
          raise Fixture::FormatError, "a YAML error occured parsing #{yaml_file_path}. Please note that YAML must be consistently indented using spaces. Tabs are not allowed. Please have a look at http://www.yaml.org/faq.html\nThe exact error was:\n  #{boom.class}: #{boom}"
        end
      elsif File.file?(csv_file_path)
        # CSV fixtures
        reader = CSV::Reader.create(erb_render(IO.read(csv_file_path)))
        header = reader.shift
        i = 0
        reader.each do |row|
          data = {}
          row.each_with_index { |cell, j| data[header[j].to_s.strip] = cell.to_s.strip }
          self["#{Inflector::underscore(@class_name)}_#{i+=1}"]= Fixture.new(data, @class_name)
        end
      elsif File.file?(deprecated_yaml_file_path)
        raise Fixture::FormatError, ".yml extension required: rename #{deprecated_yaml_file_path} to #{yaml_file_path}"
      else
        # Standard fixtures
        Dir.entries(@fixture_path).each do |file|
          path = File.join(@fixture_path, file)
          if File.file?(path) and file !~ @file_filter
            self[file] = Fixture.new(path, @class_name)
          end
        end
      end
    end

    def yaml_file_path
      "#{@fixture_path}.yml"
    end

    def deprecated_yaml_file_path
      "#{@fixture_path}.yaml"
    end

    def csv_file_path
      @fixture_path + ".csv"
    end

    def yaml_fixtures_key(path)
      File.basename(@fixture_path).split(".").first
    end

    def erb_render(fixture_content)
      ERB.new(fixture_content).result
    end
end

class Fixture #:nodoc:
  include Enumerable
  class FixtureError < StandardError#:nodoc:
  end
  class FormatError < FixtureError#:nodoc:
  end

  def initialize(fixture, class_name)
    @fixture = fixture.is_a?(Hash) ? fixture : read_fixture_file(fixture)
    @class_name = class_name
  end

  def each
    @fixture.each { |item| yield item }
  end

  def [](key)
    @fixture[key]
  end

  def to_hash
    @fixture
  end

  def key_list
    columns = @fixture.keys.collect{ |column_name| ActiveRecord::Base.connection.quote_column_name(column_name) }
    columns.join(", ")
  end

  def value_list
    @fixture.values.map { |v| ActiveRecord::Base.connection.quote(v).gsub('\\n', "\n").gsub('\\r', "\r") }.join(", ")
  end

  def find
    if Object.const_defined?(@class_name)
      klass = Object.const_get(@class_name)
      klass.find(self[klass.primary_key])
    end
  end

  private
    def read_fixture_file(fixture_file_path)
      IO.readlines(fixture_file_path).inject({}) do |fixture, line|
        # Mercifully skip empty lines.
        next if line =~ /^\s*$/

        # Use the same regular expression for attributes as Active Record.
        unless md = /^\s*([a-zA-Z][-_\w]*)\s*=>\s*(.+)\s*$/.match(line)
          raise FormatError, "#{fixture_file_path}: fixture format error at '#{line}'.  Expecting 'key => value'."
        end
        key, value = md.captures

        # Disallow duplicate keys to catch typos.
        raise FormatError, "#{fixture_file_path}: duplicate '#{key}' in fixture." if fixture[key]
        fixture[key] = value.strip
        fixture
      end
    end
end

module Test #:nodoc:
  module Unit #:nodoc:
    class TestCase #:nodoc:
      include ClassInheritableAttributes

      cattr_accessor :fixture_path
      class_inheritable_accessor :fixture_table_names
      class_inheritable_accessor :use_transactional_fixtures
      class_inheritable_accessor :use_instantiated_fixtures   # true, false, or :no_instances
      class_inheritable_accessor :pre_loaded_fixtures

      self.fixture_table_names = []
      self.use_transactional_fixtures = false
      self.use_instantiated_fixtures = true
      self.pre_loaded_fixtures = false

      @@already_loaded_fixtures = {}

      def self.fixtures(*table_names)
        table_names = table_names.flatten
        self.fixture_table_names |= table_names
        require_fixture_classes(table_names)
        setup_fixture_accessors(table_names)
      end

      def self.require_fixture_classes(table_names=nil)
        (table_names || fixture_table_names).each do |table_name| 
          begin
            require Inflector.singularize(table_name.to_s)
          rescue LoadError
            # Let's hope the developer has included it himself
          end
        end
      end

      def self.setup_fixture_accessors(table_names=nil)
        (table_names || fixture_table_names).each do |table_name|
          table_name = table_name.to_s.tr('.','_')
          define_method(table_name) do |fixture, *optionals|
            force_reload = optionals.shift
            @fixture_cache[table_name] ||= Hash.new
            @fixture_cache[table_name][fixture] = nil if force_reload
            @fixture_cache[table_name][fixture] ||= @loaded_fixtures[table_name][fixture.to_s].find
          end
        end
      end

      def self.uses_transaction(*methods)
        @uses_transaction ||= []
        @uses_transaction.concat methods.map { |m| m.to_s }
      end

      def self.uses_transaction?(method)
        @uses_transaction && @uses_transaction.include?(method.to_s)
      end

      def use_transactional_fixtures?
        use_transactional_fixtures &&
          !self.class.uses_transaction?(method_name)
      end

      def setup_with_fixtures
        if pre_loaded_fixtures && !use_transactional_fixtures
          raise RuntimeError, 'pre_loaded_fixtures requires use_transactional_fixtures' 
        end

        @fixture_cache = Hash.new

        # Load fixtures once and begin transaction.
        if use_transactional_fixtures?
          if @@already_loaded_fixtures[self.class]
            @loaded_fixtures = @@already_loaded_fixtures[self.class]
          else
            load_fixtures
            @@already_loaded_fixtures[self.class] = @loaded_fixtures
          end
          ActiveRecord::Base.lock_mutex
          ActiveRecord::Base.connection.begin_db_transaction

        # Load fixtures for every test.
        else
          @@already_loaded_fixtures[self.class] = nil
          load_fixtures
        end

        # Instantiate fixtures for every test if requested.
        instantiate_fixtures if use_instantiated_fixtures
      end

      alias_method :setup, :setup_with_fixtures

      def teardown_with_fixtures
        # Rollback changes.
        if use_transactional_fixtures?
          ActiveRecord::Base.connection.rollback_db_transaction
          ActiveRecord::Base.unlock_mutex
        end
      end

      alias_method :teardown, :teardown_with_fixtures

      def self.method_added(method)
        case method.to_s
        when 'setup'
          unless method_defined?(:setup_without_fixtures)
            alias_method :setup_without_fixtures, :setup
            define_method(:setup) do
              setup_with_fixtures
              setup_without_fixtures
            end
          end
        when 'teardown'
          unless method_defined?(:teardown_without_fixtures)
            alias_method :teardown_without_fixtures, :teardown
            define_method(:teardown) do
              teardown_without_fixtures
              teardown_with_fixtures
            end
          end
        end
      end

      private
        def load_fixtures
          @loaded_fixtures = {}
          fixtures = Fixtures.create_fixtures(fixture_path, fixture_table_names)
          unless fixtures.nil?
            if fixtures.instance_of?(Fixtures)
              @loaded_fixtures[fixtures.table_name] = fixtures
            else
              fixtures.each { |f| @loaded_fixtures[f.table_name] = f }
            end
          end
        end

        # for pre_loaded_fixtures, only require the classes once. huge speed improvement
        @@required_fixture_classes = false

        def instantiate_fixtures
          if pre_loaded_fixtures
            raise RuntimeError, 'Load fixtures before instantiating them.' if Fixtures.all_loaded_fixtures.empty?
            unless @@required_fixture_classes
              self.class.require_fixture_classes Fixtures.all_loaded_fixtures.keys
              @@required_fixture_classes = true
            end
            Fixtures.instantiate_all_loaded_fixtures(self, load_instances?)
          else
            raise RuntimeError, 'Load fixtures before instantiating them.' if @loaded_fixtures.nil?
            @loaded_fixtures.each do |table_name, fixtures|
              Fixtures.instantiate_fixtures(self, table_name, fixtures, load_instances?)
            end
          end
        end

        def load_instances?
          use_instantiated_fixtures != :no_instances
        end
    end

  end
end