Django simple SQL log

Goal: provide a middleware that inserts start/stop annotations that would land on the SQL logs.

Like this:

2014-12-08 09:33:58 CET LOG:  duration: 0.174 ms  statement: BEGIN
2014-12-08 09:33:58 CET LOG:  duration: 0.502 ms  statement: SET TIME ZONE 'UTC'
2014-12-08 09:33:58 CET LOG:  duration: 0.053 ms  statement: COMMIT
2014-12-08 09:33:58 CET LOG:  duration: 0.228 ms  statement: SHOW default_transaction_isolation
2014-12-08 09:33:58 CET LOG:  duration: 0.043 ms  statement: BEGIN
2014-12-08 09:33:58 CET LOG:  duration: 0.354 ms  statement: SELECT 'django_sql_log_demo.views.Index_START'
2014-12-08 09:33:58 CET LOG:  duration: 1.221 ms  statement: SELECT "dummy_article"."id", "dummy_article"."title", "dummy_article"."body" FROM "dummy_article"
2014-12-08 09:33:58 CET LOG:  duration: 0.118 ms  statement: SELECT 'django_sql_log_demo.views.Index_STOP'
2014-12-08 09:33:58 CET LOG:  duration: 0.067 ms  statement: ROLLBACK
2014-12-08 09:33:59 CET LOG:  duration: 0.179 ms  statement: BEGIN
2014-12-08 09:33:59 CET LOG:  duration: 0.513 ms  statement: SET TIME ZONE 'UTC'
2014-12-08 09:33:59 CET LOG:  duration: 0.054 ms  statement: COMMIT
2014-12-08 09:33:59 CET LOG:  duration: 0.231 ms  statement: SHOW default_transaction_isolation
2014-12-08 09:34:00 CET LOG:  duration: 117.999 ms  statement: DROP DATABASE "test_hello_world"

The available middleware has been tested only with Postgresql databases, but it should work with other SQL-based RDBMs.

Usage

Add this package to your requirements, and install it the usual way. You don't have to add the application to the INSTALLED_APPS, there's no model to sync.

Add the middleware like this:

MIDDLEWARE_CLASSES = (
    'django_sql_log.middleware.SQLLoggingMiddleware',
    # ...
)

Although the order of the middlewares is not crucial, it is better to make sure that the middleware is near the first place in the list.

Log format string

By default, the log format string is:

{full_name}_{phase}

In the demo site, this would result in:

django_sql_log_demo.views.Index_START

for the START event in the log.

You can customize this format by adding the DJANGO_SQL_LOG_FORMAT to your settings. Available format variables are (with correspondance in the demo tests):

• module_name: django_sql_log_demo.views,
• func_name: Index,
• full_name: django_sql_log_demo.views.Index,
• phase: START or STOP,

Hacking

If you want to run the test-suite, have a look at the settings_pg.py file in your demo/django_sql_log_demo directory.

It carries the basic database settings you'll need to run tox tests and eventually store demo data. Hopefully, by simply creating a settings_pg_local.py file, you can override the default credentials to fit your Postgresql server specifics.

Please bear in mind that the database you'll have to connect to must exist on this server, and that your PG user should be able to create and delete databases.

With tox installed, simply run the command tox. This should run the tests for Sqlite and postgresql environments, if ready.

Logging in Postgresql

For you information, logs are not activated by default in postgresql settings. To make sure your log file will display the START/STOP events, go edit your postgresql.conf file and set this variable:

log_min_duration_statement = 0

For other database systems, please refer to the official documentation.

This software is published under the terms of the MIT License. Please see the LICENSE file for more information.