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
|
# frozen_string_literal: true
module Gitlab
module Database
module QueryAnalyzers
class PreventCrossDatabaseModification < Database::QueryAnalyzers::Base
CrossDatabaseModificationAcrossUnsupportedTablesError = Class.new(QueryAnalyzerError)
QUERY_LIMIT = 10
# This method will allow cross database modifications within the block
# Example:
#
# allow_cross_database_modification_within_transaction(url: 'url-to-an-issue') do
# create(:build) # inserts ci_build and project record in one transaction
# end
def self.allow_cross_database_modification_within_transaction(url:, &blk)
self.with_suppressed(true, &blk)
end
# This method will prevent cross database modifications within the block
# if it was allowed previously
def self.with_cross_database_modification_prevented(&blk)
self.with_suppressed(false, &blk)
end
# This method will temporary ignore the given tables in a current transaction
# This is meant to disable `PreventCrossDB` check for some well known failures
def self.temporary_ignore_tables_in_transaction(tables, url:, &blk)
return yield unless context&.dig(:ignored_tables)
begin
prev_ignored_tables = context[:ignored_tables]
context[:ignored_tables] = prev_ignored_tables + tables
yield
ensure
context[:ignored_tables] = prev_ignored_tables
end
end
def self.begin!
super
context.merge!({
transaction_depth_by_db: Hash.new { |h, k| h[k] = 0 },
modified_tables_by_db: Hash.new { |h, k| h[k] = Set.new },
ignored_tables: [],
queries: []
})
end
def self.enabled?
::Feature::FlipperFeature.table_exists? &&
Feature.enabled?(:detect_cross_database_modification, type: :ops)
end
def self.requires_tracking?(parsed)
# The transaction boundaries always needs to be tracked regardless of suppress behavior
self.transaction_begin?(parsed) || self.transaction_end?(parsed)
end
# rubocop:disable Metrics/AbcSize
def self.analyze(parsed)
database = ::Gitlab::Database.db_config_name(parsed.connection)
sql = parsed.sql
# We ignore BEGIN in tests as this is the outer transaction for
# DatabaseCleaner
if self.transaction_begin?(parsed)
context[:transaction_depth_by_db][database] += 1
return
elsif self.transaction_end?(parsed)
context[:transaction_depth_by_db][database] -= 1
if context[:transaction_depth_by_db][database] == 0
context[:modified_tables_by_db][database].clear
clear_queries
# Attempt to troubleshoot https://gitlab.com/gitlab-org/gitlab/-/issues/351531
::CrossDatabaseModification::TransactionStackTrackRecord.log_gitlab_transactions_stack(action: :end_of_transaction)
elsif context[:transaction_depth_by_db][database] < 0
context[:transaction_depth_by_db][database] = 0
raise CrossDatabaseModificationAcrossUnsupportedTablesError, "Misaligned cross-DB transactions discovered at query #{sql}. This could be a bug in #{self.class} or a valid issue to investigate. Read more at https://docs.gitlab.com/ee/development/database/multiple_databases.html#removing-cross-database-transactions ."
end
return
end
return unless self.in_transaction?
return if in_factory_bot_create?
# PgQuery might fail in some cases due to limited nesting:
# https://github.com/pganalyze/pg_query/issues/209
tables = sql.downcase.include?(' for update') ? parsed.pg.tables : parsed.pg.dml_tables
# We have some code where plans and gitlab_subscriptions are lazily
# created and this causes lots of spec failures
# https://gitlab.com/gitlab-org/gitlab/-/issues/343394
tables -= %w[plans gitlab_subscriptions]
# Ignore some tables
tables -= context[:ignored_tables].to_a
return if tables.empty?
# All migrations will write to schema_migrations in the same transaction.
# It's safe to ignore this since schema_migrations exists in all
# databases
return if tables == ['schema_migrations']
add_to_queries(sql)
context[:modified_tables_by_db][database].merge(tables)
all_tables = context[:modified_tables_by_db].values.flat_map(&:to_a)
schemas = ::Gitlab::Database::GitlabSchema.table_schemas!(all_tables)
schemas += ApplicationRecord.gitlab_transactions_stack
unless ::Gitlab::Database::GitlabSchema.cross_transactions_allowed?(schemas, all_tables)
messages = []
messages << "Cross-database data modification of '#{schemas.to_a.join(", ")}' were detected within " \
"a transaction modifying the '#{all_tables.to_a.join(", ")}' tables. "
messages << "Please refer to https://docs.gitlab.com/ee/development/database/multiple_databases.html#removing-cross-database-transactions " \
"for details on how to resolve this exception."
messages += cleaned_queries
raise CrossDatabaseModificationAcrossUnsupportedTablesError, messages.join("\n\n")
end
rescue CrossDatabaseModificationAcrossUnsupportedTablesError => e
::Gitlab::ErrorTracking.track_exception(e, { gitlab_schemas: schemas, tables: all_tables, query: parsed.sql })
raise if dev_or_test_env?
end
# rubocop:enable Metrics/AbcSize
def self.transaction_begin?(parsed)
# We ignore BEGIN or START in tests
unless Rails.env.test?
return true if transaction_stmt?(parsed, :TRANS_STMT_BEGIN)
return true if transaction_stmt?(parsed, :TRANS_STMT_START)
end
# SAVEPOINT
return true if transaction_stmt?(parsed, :TRANS_STMT_SAVEPOINT)
false
end
def self.transaction_end?(parsed)
# We ignore ROLLBACK or COMMIT in tests
unless Rails.env.test?
return true if transaction_stmt?(parsed, :TRANS_STMT_COMMIT)
return true if transaction_stmt?(parsed, :TRANS_STMT_COMMIT_PREPARED)
return true if transaction_stmt?(parsed, :TRANS_STMT_ROLLBACK)
return true if transaction_stmt?(parsed, :TRANS_STMT_ROLLBACK_PREPARED)
end
# RELEASE (SAVEPOINT) or ROLLBACK TO (SAVEPOINT)
return true if transaction_stmt?(parsed, :TRANS_STMT_RELEASE)
return true if transaction_stmt?(parsed, :TRANS_STMT_ROLLBACK_TO)
false
end
# Known kinds: https://github.com/pganalyze/pg_query/blob/f6588703deb9d7a94b87b34b7c3bab240087fbc4/ext/pg_query/include/nodes/parsenodes.h#L3050
def self.transaction_stmt?(parsed, kind)
parsed.pg.tree.stmts.map(&:stmt).any? do |stmt|
stmt.node == :transaction_stmt && stmt.transaction_stmt.kind == kind
end
end
def self.dev_or_test_env?
Gitlab.dev_or_test_env?
end
def self.clear_queries
return unless dev_or_test_env?
context[:queries].clear
end
def self.add_to_queries(sql)
return unless dev_or_test_env?
context[:queries].push(sql)
end
def self.cleaned_queries
return [] unless dev_or_test_env?
context[:queries].last(QUERY_LIMIT).each_with_index.map do |sql, i|
"#{i}: #{sql}"
end
end
def self.in_transaction?
context[:transaction_depth_by_db].values.any?(&:positive?)
end
# We ignore execution in the #create method from FactoryBot
# because it is not representative of real code we run in
# production. There are far too many false positives caused
# by instantiating objects in different `gitlab_schema` in a
# FactoryBot `create`.
def self.in_factory_bot_create?
Rails.env.test? && caller_locations.any? do |l|
l.path.end_with?('lib/factory_bot/evaluation.rb') && l.label == 'create' ||
l.path.end_with?('lib/factory_bot/strategy/create.rb') ||
l.path.end_with?('lib/factory_bot/strategy/build.rb') ||
l.path.end_with?('shoulda/matchers/active_record/validate_uniqueness_of_matcher.rb') && l.label == 'create_existing_record'
end
end
end
end
end
end
|