Add mysql-connector instrumentor support for sqlcommenting

[tammy-baylis-swi]

Description

Updates mysql-connector instrumentor to support sqlcommenting.

To leverage existing code and reduce duplication, this updates DB-API integration instrumentor with new abstract classes BaseTracedConnectionProxy and BaseTracedCursorProxy, while keeping uses by aiopg, psycopg2, psycopg instrumentors the same.

To perform checks specific to mysql-connector, its instrumentor has new custom subclasses and methods that extend from DB-API integration, sort of like what psycopg instrumentor does. This is to enable_commenter at the db client cursor level (instead of DB-API level) and support mixes of cursor types instrumented. See below for More background.

Fixes #2902

Replaces other PR #2943

More about db client cursors and sqlcommenting

If an app-side, mysql-connector cursor is set with prepared=True, mysql-connector will perform native prepared statement execution (see docs here). If sqlcommenting is enabled with mysql-connector, native prepared statement execution would result in inaccuracy and a notable performance penalty. In the example MySQL general log below, we see multiple pairs of Prepare + Execute with the same statement after performing a parameterized query 3 times when prepared=True:

2024-11-19T01:22:04.911237Z	  770 Prepare	SELECT * FROM city WHERE id = ?
2024-11-19T01:22:04.911404Z	  770 Reset stmt
2024-11-19T01:22:04.911743Z	  770 Execute	SELECT * FROM city WHERE id = '1818'
2024-11-19T01:22:05.587278Z	  770 Prepare	SELECT * FROM city WHERE id = ?
2024-11-19T01:22:05.587438Z	  770 Reset stmt
2024-11-19T01:22:05.587728Z	  770 Execute	SELECT * FROM city WHERE id = '1818'
2024-11-19T01:22:06.179149Z	  770 Prepare	SELECT * FROM city WHERE id = ?
2024-11-19T01:22:06.179237Z	  770 Reset stmt
2024-11-19T01:22:06.179513Z	  770 Execute	SELECT * FROM city WHERE id = '1818'

Adding the same sqlcomment to both Prepare and Execute statements would break the 1:1 correlation between sqlcomment and span. It would also take more resources to append sqlcomment to both.

If queries are submitted as single Query statements (when prepared=False), then the 1:1 correlation is maintained:

2024-11-19T01:21:39.188226Z	  770 Query	SELECT * FROM city WHERE id = '1818'
2024-11-19T01:21:40.129791Z	  770 Query	SELECT * FROM city WHERE id = '1818'
2024-11-19T01:21:40.922572Z	  770 Query	SELECT * FROM city WHERE id = '1818'

Therefore, new helper is_mysql_connector_cursor_prepared checks and disables sqlcommenting only for that cursor if prepared=True. Other cursors will still be traced.

Currently, native prepared statement execution of MySQL statements is only a mysql-connector feature, and not in mysqlclient nor PyMySQL.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Unit tests

• tox -e py312-test-instrumentation-dbapi
• tox -e py312-test-instrumentation-mysql-0
• tox -e py312-test-instrumentation-mysql-1

Manual testing

• App instrumented with mysql-connector
• App instrumented with mysqlclient, to check that DB-API functionality still works
• App instrumented with psycopg2, to check that DB-API inheritance still works elsewhere

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated