[WIP] Support ActiveRecord::ReadOnlyError

[yahonda]

Refer rails/rails#34505 rails/rails#34632

$ cd activerecord
$ ARCONN=oracle bin/test test/cases/adapter_test.rb test/cases/base_test.rb -n /preventing_writes/
Using oracle
Run options: -n /preventing_writes/ --seed 62121

# Running:

.F

Failure:
ActiveRecord::AdapterTest#test_errors_when_a_delete_query_is_called_while_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/adapter_test.rb:206]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/adapter_test.rb:203

F

Failure:
ActiveRecord::AdapterTest#test_errors_when_an_update_query_is_called_while_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/adapter_test.rb:192]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/adapter_test.rb:189

F

Failure:
ActiveRecord::AdapterTest#test_errors_when_an_insert_query_is_called_while_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/adapter_test.rb:178]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/adapter_test.rb:177

.F

Failure:
BasicsTest#test_preventing_writes_with_multiple_handlers [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1594]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/base_test.rb:1591

F

Failure:
BasicsTest#test_updating_a_record_raises_if_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1521]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/base_test.rb:1518

F

Failure:
BasicsTest#test_creating_a_record_raises_if_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1509]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/base_test.rb:1508

F

Failure:
BasicsTest#test_an_empty_transaction_does_not_raise_if_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1560]:
1 instead of 2 queries were executed.
Queries:
SAVEPOINT active_record_1.
Expected: 2
  Actual: 1


bin/test test/cases/base_test.rb:1558

F

Failure:
BasicsTest#test_preventing_writes_applies_to_all_connections_on_a_handler [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1569]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/base_test.rb:1568

.F

Failure:
BasicsTest#test_deleting_a_record_raises_if_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1533]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/base_test.rb:1530

F

Failure:
BasicsTest#test_an_explain_query_does_not_raise_if_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/base_test.rb:1554]:
3 instead of 2 queries were executed.
Queries:
SELECT "BIRDS".* FROM "BIRDS" WHERE "BIRDS"."NAME" = :a1
EXPLAIN PLAN FOR SELECT "BIRDS".* FROM "BIRDS" WHERE "BIRDS"."NAME" = :a1
SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY).
Expected: 2
  Actual: 3


bin/test test/cases/base_test.rb:1550



Finished in 41.900314s, 0.3103 runs/s, 0.4296 assertions/s.
13 runs, 18 assertions, 10 failures, 0 errors, 0 skips
$

[yahonda]

One of these failures are due to SAVEPOINT statement executed, which is NOT a write query.

• test_errors_when_a_delete_query_is_called_while_preventing_writes fails with print debug code

$ ARCONN=oracle bin/test test/cases/adapter_test.rb -n test_errors_when_a_delete_query_is_called_while_preventing_writes
Using oracle
Run options: -n test_errors_when_a_delete_query_is_called_while_preventing_writes --seed 60387

# Running:

"=========================================="
"preventing_writes?: true"
"write_query?: false"
"sql: SAVEPOINT active_record_1"
"1111111111111111111111"
F

Failure:
ActiveRecord::AdapterTest#test_errors_when_a_delete_query_is_called_while_preventing_writes [/home/yahonda/git/rails/activerecord/test/cases/adapter_test.rb:206]:
ActiveRecord::ReadOnlyError expected but nothing was raised.


bin/test test/cases/adapter_test.rb:203



Finished in 0.228083s, 4.3844 runs/s, 4.3844 assertions/s.
1 runs, 1 assertions, 1 failures, 0 errors, 0 skips
$

• Print debug in Oracle enhanced adapter

$ git diff
diff --git a/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb b/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
index 085b317b..09b5811b 100644
--- a/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
+++ b/lib/active_record/connection_adapters/oracle_enhanced/database_statements.rb
@@ -17,6 +17,10 @@ module ActiveRecord

         # Executes a SQL statement
         def execute(sql, name = nil)
+          p '=========================================='
+          p "preventing_writes?: #{preventing_writes?}"
+          p "write_query?: #{write_query?(sql)}"
+          p "sql: #{sql}"
           if preventing_writes? && write_query?(sql)
             raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
           end
$

• Print debug code in Active Record

+++ b/activerecord/test/cases/adapter_test.rb
@@ -207,6 +207,7 @@ def test_errors_when_a_delete_query_is_called_while_preventing_writes
         assert_raises(ActiveRecord::ReadOnlyError) do
           @connection_handler.while_preventing_writes do
             @connection.transaction do
+              p '1111111111111111111111'
               @connection.delete("DELETE FROM subscribers WHERE nick = '138853948594'")
             end
           end
$

[yahonda]

• The same test pass with mysql2 adapter

Here the first statement is DELETE, which is an expected one.

"=========================================="
"preventing_writes?: true"
"write_query?: true"
"sql: DELETE FROM subscribers WHERE nick = '138853948594'"
"=========================================="

$ ARCONN=mysql2 bin/test test/cases/adapter_test.rb -n test_errors_when_a_delete_query_is_called_while_preventing_writes
Using mysql2
"=========================================="
"preventing_writes?: false"
"write_query?: false"
"sql: SET NAMES utf8mb4 COLLATE utf8mb4_unicode_ci,  @@SESSION.sql_mode = CONCAT(CONCAT(@@sql_mode, ',STRICT_ALL_TABLES'), ',NO_AUTO_VALUE_ON_ZERO'),  @@SESSION.sql_auto_is_null = 0, @@SESSION.wait_timeout = 2147483"
Run options: -n test_errors_when_a_delete_query_is_called_while_preventing_writes --seed 65422

# Running:

"=========================================="
"preventing_writes?: false"
"write_query?: false"
"sql: BEGIN"
"=========================================="
"preventing_writes?: false"
"write_query?: false"
"sql: BEGIN"
"=========================================="
"preventing_writes?: false"
"write_query?: true"
"sql: INSERT INTO subscribers(nick) VALUES ('138853948594')"
"1111111111111111111111"
"=========================================="
"preventing_writes?: true"
"write_query?: true"
"sql: DELETE FROM subscribers WHERE nick = '138853948594'"
"=========================================="
"preventing_writes?: false"
"write_query?: false"
"sql: ROLLBACK"
"=========================================="
"preventing_writes?: false"
"write_query?: false"
"sql: ROLLBACK"
.

Finished in 0.010384s, 96.3020 runs/s, 192.6040 assertions/s.
1 runs, 2 assertions, 0 failures, 0 errors, 0 skips
$

$ git diff
diff --git a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
index bbcdc96cdc..4b4a24c68a 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
@@ -37,6 +37,10 @@ def explain(arel, binds = [])

         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil)
+          p '=========================================='
+          p "preventing_writes?: #{preventing_writes?}"
+          p "write_query?: #{write_query?(sql)}"
+          p "sql: #{sql}"
           if preventing_writes? && write_query?(sql)
             raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
           end
diff --git a/activerecord/test/cases/adapter_test.rb b/activerecord/test/cases/adapter_test.rb
index 0bc617edbe..885c32be7b 100644
--- a/activerecord/test/cases/adapter_test.rb
+++ b/activerecord/test/cases/adapter_test.rb
@@ -207,6 +207,7 @@ def test_errors_when_a_delete_query_is_called_while_preventing_writes
         assert_raises(ActiveRecord::ReadOnlyError) do
           @connection_handler.while_preventing_writes do
             @connection.transaction do
+              p '1111111111111111111111'
               @connection.delete("DELETE FROM subscribers WHERE nick = '138853948594'")
             end
           end
$

[yahonda]

Looks like Oracle enhanced adapter needs rails/rails#32647 support first.

Because create_savepoint method is called in the following order.

https://github.com/rails/rails/blob/60e19c6d6cb60159af4e2247f29d2cea375a21d6/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb#L234

https://github.com/rails/rails/blob/60e19c6d6cb60159af4e2247f29d2cea375a21d6/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb#L161

Oracle database itself does not need BEGIN to start a transaction, then I was aware of rails/rails#32647 but have not implemented it.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[yahonda]

Let me just ping this issue.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.