aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/test/locking_test.rb
blob: 97fbfaaeb18921f661669b5ec94bdb8acb522c09 (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
require 'abstract_unit'
require 'fixtures/person'
require 'fixtures/reader'
require 'fixtures/legacy_thing'

class LockWithoutDefault < ActiveRecord::Base; end

class LockWithCustomColumnWithoutDefault < ActiveRecord::Base
  set_table_name :lock_without_defaults_cust
  set_locking_column :custom_lock_version
end

class ReadonlyFirstNamePerson < Person
  attr_readonly :first_name
end

class OptimisticLockingTest < Test::Unit::TestCase
  fixtures :people, :legacy_things

  # need to disable transactional fixtures, because otherwise the sqlite3
  # adapter (at least) chokes when we try and change the schema in the middle
  # of a test (see test_increment_counter_*).
  self.use_transactional_fixtures = false

  def test_lock_existing
    p1 = Person.find(1)
    p2 = Person.find(1)
    assert_equal 0, p1.lock_version
    assert_equal 0, p2.lock_version

    p1.save!
    assert_equal 1, p1.lock_version
    assert_equal 0, p2.lock_version

    assert_raises(ActiveRecord::StaleObjectError) { p2.save! }
  end
  
  def test_lock_repeating
    p1 = Person.find(1)
    p2 = Person.find(1)
    assert_equal 0, p1.lock_version
    assert_equal 0, p2.lock_version

    p1.save!
    assert_equal 1, p1.lock_version
    assert_equal 0, p2.lock_version

    assert_raises(ActiveRecord::StaleObjectError) { p2.save! }
    assert_raises(ActiveRecord::StaleObjectError) { p2.save! }
  end

  def test_lock_new
    p1 = Person.new(:first_name => 'anika')
    assert_equal 0, p1.lock_version

    p1.save!
    p2 = Person.find(p1.id)
    assert_equal 0, p1.lock_version
    assert_equal 0, p2.lock_version

    p1.save!
    assert_equal 1, p1.lock_version
    assert_equal 0, p2.lock_version

    assert_raises(ActiveRecord::StaleObjectError) { p2.save! }
  end

  def test_lock_column_name_existing
    t1 = LegacyThing.find(1)
    t2 = LegacyThing.find(1)
    assert_equal 0, t1.version
    assert_equal 0, t2.version

    t1.save!
    assert_equal 1, t1.version
    assert_equal 0, t2.version

    assert_raises(ActiveRecord::StaleObjectError) { t2.save! }
  end

  def test_lock_column_is_mass_assignable
    p1 = Person.create(:first_name => 'bianca')
    assert_equal 0, p1.lock_version
    assert_equal p1.lock_version, Person.new(p1.attributes).lock_version

    p1.save!
    assert_equal 1, p1.lock_version
    assert_equal p1.lock_version, Person.new(p1.attributes).lock_version
  end

  def test_lock_without_default_sets_version_to_zero
    t1 = LockWithoutDefault.new
    assert_equal 0, t1.lock_version
  end

  def test_lock_with_custom_column_without_default_sets_version_to_zero
    t1 = LockWithCustomColumnWithoutDefault.new
    assert_equal 0, t1.custom_lock_version
  end

  def test_readonly_attributes
    assert_equal Set.new([ 'first_name' ]), ReadonlyFirstNamePerson.readonly_attributes

    p = ReadonlyFirstNamePerson.create(:first_name => "unchangeable name")
    p.reload
    assert_equal "unchangeable name", p.first_name

    p.update_attributes(:first_name => "changed name")
    p.reload
    assert_equal "unchangeable name", p.first_name
  end

  { :lock_version => Person, :custom_lock_version => LegacyThing }.each do |name, model|
    define_method("test_increment_counter_updates_#{name}") do
      counter_test model, 1 do |id|
        model.increment_counter :test_count, id
      end
    end

    define_method("test_decrement_counter_updates_#{name}") do
      counter_test model, -1 do |id|
        model.decrement_counter :test_count, id
      end
    end

    define_method("test_update_counters_updates_#{name}") do
      counter_test model, 1 do |id|
        model.update_counters id, :test_count => 1
      end
    end
  end

  private

    def add_counter_column_to(model)
      model.connection.add_column model.table_name, :test_count, :integer, :null => false, :default => 0
      model.reset_column_information
      # OpenBase does not set a value to existing rows when adding a not null default column
      model.update_all(:test_count => 0) if current_adapter?(:OpenBaseAdapter)
    end

    def remove_counter_column_from(model)
      model.connection.remove_column model.table_name, :test_count
      model.reset_column_information
    end

    def counter_test(model, expected_count)
      add_counter_column_to(model)
      object = model.find(:first)
      assert_equal 0, object.test_count
      assert_equal 0, object.send(model.locking_column)
      yield object.id
      object.reload
      assert_equal expected_count, object.test_count
      assert_equal 1, object.send(model.locking_column)
    ensure
      remove_counter_column_from(model)
    end
end


# TODO: test against the generated SQL since testing locking behavior itself
# is so cumbersome. Will deadlock Ruby threads if the underlying db.execute
# blocks, so separate script called by Kernel#system is needed.
# (See exec vs. async_exec in the PostgreSQL adapter.)

# TODO: The SQL Server, Sybase, and OpenBase adapters currently have no support for pessimistic locking

unless current_adapter?(:SQLServerAdapter, :SybaseAdapter, :OpenBaseAdapter)
  class PessimisticLockingTest < Test::Unit::TestCase
    self.use_transactional_fixtures = false
    fixtures :people, :readers

    def setup
      # Avoid introspection queries during tests.
      Person.columns; Reader.columns

      @allow_concurrency = ActiveRecord::Base.allow_concurrency
      ActiveRecord::Base.allow_concurrency = true
    end

    def teardown
      ActiveRecord::Base.allow_concurrency = @allow_concurrency
    end

    # Test typical find.
    def test_sane_find_with_lock
      assert_nothing_raised do
        Person.transaction do
          Person.find 1, :lock => true
        end
      end
    end

    # Test scoped lock.
    def test_sane_find_with_scoped_lock
      assert_nothing_raised do
        Person.transaction do
          Person.with_scope(:find => { :lock => true }) do
            Person.find 1
          end
        end
      end
    end

    # PostgreSQL protests SELECT ... FOR UPDATE on an outer join.
    unless current_adapter?(:PostgreSQLAdapter)
      # Test locked eager find.
      def test_eager_find_with_lock
        assert_nothing_raised do
          Person.transaction do
            Person.find 1, :include => :readers, :lock => true
          end
        end
      end
    end

    # Locking a record reloads it.
    def test_sane_lock_method
      assert_nothing_raised do
        Person.transaction do
          person = Person.find 1
          old, person.first_name = person.first_name, 'fooman'
          person.lock!
          assert_equal old, person.first_name
        end
      end
    end

    if current_adapter?(:PostgreSQLAdapter, :OracleAdapter)
      def test_no_locks_no_wait
        first, second = duel { Person.find 1 }
        assert first.end > second.end
      end

      def test_second_lock_waits
        assert [0.2, 1, 5].any? { |zzz|
          first, second = duel(zzz) { Person.find 1, :lock => true }
          second.end > first.end
        }
      end

      protected
        def duel(zzz = 5)
          t0, t1, t2, t3 = nil, nil, nil, nil

          a = Thread.new do
            t0 = Time.now
            Person.transaction do
              yield
              sleep zzz       # block thread 2 for zzz seconds
            end
            t1 = Time.now
          end

          b = Thread.new do
            sleep zzz / 2.0   # ensure thread 1 tx starts first
            t2 = Time.now
            Person.transaction { yield }
            t3 = Time.now
          end

          a.join
          b.join

          assert t1 > t0 + zzz
          assert t2 > t0
          assert t3 > t2
          [t0.to_f..t1.to_f, t2.to_f..t3.to_f]
        end
    end
  end
end