Django SQL Sniffer

A simple command line tool for analyzing Django ORM SQL execution from a running process. Minimally invasive and granular - no need to change the logging config or the source code of the target process, and no need to restart the process.

Usage

Install though pip

pip install django-sql-sniffer

Run the tool by passing it the target process id

django-sql-sniffer -p 76441

Ctrl + C to stop and show the query stats summary. Take a look at a short demo: By default, stats summary shows queries sorted by max duration; the possible options include:

• -t print queries in tail mode, i.e. as they are executed
• -c sort stats summary by query count
• -s sort stats summary by total combined query duration
• -n set the number of top queries to display in stats summary
• -v for verbose logging mode on both the client and server side
• if OS supports SIGINFO signal press Ctrl + T to display snapshot stats summary without killing the process

How it works

The tool is composed out of a client and a server. Running django-sql-sniffer starts the server, which then injects the client into the running process using GDB/LLDB and waits for it to connect. The client monkey patches the Django DB cursor and starts streaming queries to the server as they are executed. The queries are then collected and analyzed on the server side.
Finally, when the server gets a shutdown signal, it stops the client which in turn rolls back the monkey patch leaving the target process in the original state.