README.md

django-query-prefixer

The Django Query Prefixer allows you to prepend annotations to every query executed within your Django project. This can be useful for monitoring. By adding custom prefixes to queries, you can gain insights into their origin, and can track their performance in a more organized manner.

Installation

You can install django-query-prefixer using pip:

pip install django-query-prefixer

Usage

1. Change database engine in your settings.py to django_query_prefixer.backends.<database backend>.

DATABASES = {
    "default": {
        "ENGINE": "django_query_prefixer.backends.postgresql",
        "HOST": "127.0.0.1",
        "NAME": "postgres",
        "PASSWORD": "postgres",
        "USER": "postgres",
    }
}

2. (Optional) Add django_query_prefixer.middlewares.request_route to the MIDDLEWARE list. This middleware adds route and view_name prefixes to SQL queries.

MIDDLEWARE = [
    "django_query_prefixer.middlewares.request_route",
    # ... 
]

3. Now, whenever queries are executed in your Django project, the configured prefixes will be automatically added to those queries. For example, a query like this:

User.objects.filter(username='bob')

will be executed as:

/* view_name=example route=/example */ SELECT ... FROM "auth_user" WHERE ("auth_user"."username" = 'bob')

You can add additional context to queries using the sql_prefixes contextmanager:

from django_query_prefixer import sql_prefixes 

with sql_prefixes(user_id=request.user.id, foo="bar"):
    User.objects.filter(username='bob')

/* user_id=X foo=bar view_name=example route=/example */ SELECT ... FROM "auth_user" WHERE ("auth_user"."username" = 'bob')

Contributing

Contributions to django-query-prefixer are welcome! If you find a bug, want to add a new feature, or improve the documentation, please open an issue or submit a pull request in the GitHub repository.