initial commit

.github/workflows/test.yaml

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+name: Test
+on: [push]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["3.11", "3.12"]
+        django-version: ["4.2", "5.0"]
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: 'pip'
+      # we don't actually install from requirements.txt because the only dependency
+      # (currently) is django
+      - run: pip install Django~=${{ matrix.django-version }}
+      - run: make test
+
+

.gitignore

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+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/latest/usage/project/#working-with-version-control
+.pdm.toml
+.pdm-python
+.pdm-build/
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/
+

.tool-versions

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+python 3.12.4

LICENSE

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+Copyright 2016 Joshua Carp
+Copyright 2024 Tao Bojlén
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

Makefile

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+install:
+	uv pip compile requirements.in -o requirements.txt && uv pip compile requirements-dev.in -o requirements-dev.txt && uv pip install -r requirements.txt && uv pip install -r requirements-dev.txt
+
+test:
+	pytest -s

README.md

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+# queryspy
+
+This library catches N+1s in your Django project.
+
+## Features
+
+- Raises an error when N+1s are detected
+- TODO: configurable thresholds
+- TODO: allowlist
+- TODO: catches unused eager loads
+- Well-tested
+- No dependencies
+
+## Acknowledgements
+
+This library draws very heavily on jmcarp's [nplusone](https://github.com/jmcarp/nplusone/).
+It's not *exactly* a fork, but not far from it.
+
+## Installation
+
+TODO.
+
+## Contributing
+
+1. First, install [uv](https://github.com/astral-sh/uv).
+2. Create a virtual env using `uv venv` and activate it with `source .venv/bin/activate`.
+3. Run `make install` to install dev dependencies.
+4. To run tests, run `make test`.
+

pyproject.toml

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+[tool.ruff]
+line-length = 79
+
+[tool.ruff.lint]
+extend-select = [
+    "I", # isort
+    "N", # naming
+    "B", # bugbear
+    "FIX", # disallow FIXME/TODO comments
+    "F", # pyflakes
+]
+
+[tool.pytest.ini_options]
+DJANGO_SETTINGS_MODULE = "djangoproject.settings"
+pythonpath = ["src", "tests"]
+testpaths = ["tests"]
+addopts = "--nomigrations"

requirements-dev.in

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+# ensure that dev deps are constrained to production deps
+-c requirements.txt
+
+pytest~=8.2.2
+pytest-django~=4.8.0
+factory-boy~=3.3.0
+ruff~=0.5.0

requirements-dev.txt

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+# This file was autogenerated by uv via the following command:
+#    uv pip compile requirements-dev.in -o requirements-dev.txt
+factory-boy==3.3.0
+    # via -r requirements-dev.in
+faker==26.0.0
+    # via factory-boy
+iniconfig==2.0.0
+    # via pytest
+packaging==24.1
+    # via pytest
+pluggy==1.5.0
+    # via pytest
+pytest==8.2.2
+    # via
+    #   -r requirements-dev.in
+    #   pytest-django
+pytest-django==4.8.0
+    # via -r requirements-dev.in
+python-dateutil==2.9.0.post0
+    # via faker
+ruff==0.5.0
+    # via -r requirements-dev.in
+six==1.16.0
+    # via python-dateutil

requirements.in

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+Django~=5.0

requirements.txt

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+# This file was autogenerated by uv via the following command:
+#    uv pip compile requirements.in -o requirements.txt
+asgiref==3.8.1
+    # via django
+django==5.0.6
+    # via -r requirements.in
+sqlparse==0.5.0
+    # via django

src/queryspy/apps.py

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+from django.apps import AppConfig
+
+from .patch import patch
+
+# from . import ugh
+
+
+class QuerySpyConfig(AppConfig):
+    name = "queryspy"
+
+    def ready(self):
+        patch()
+        pass

src/queryspy/errors.py

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+class QuerySpyError(Exception):
+    pass
+
+
+class NPlusOneError(QuerySpyError):
+    pass

src/queryspy/listeners.py

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+from abc import ABC, abstractmethod
+from collections import defaultdict
+from typing import Type
+
+from django.db import models
+
+from .errors import NPlusOneError
+
+ModelAndField = tuple[Type[models.Model], str]
+THRESHOLD = 2
+
+
+class Listener(ABC):
+    @abstractmethod
+    def notify(self, *args, **kwargs): ...
+
+
+class NPlusOneListener(Listener):
+    counts: dict[ModelAndField, int]
+
+    def __init__(self):
+        self.counts = defaultdict(int)
+
+    def notify(self, model: Type[models.Model], field: str):
+        key = (model, field)
+        self.counts[key] += 1
+        count = self.counts[key]
+        if count >= THRESHOLD:
+            raise NPlusOneError("BAD!")
+
+
+n_plus_one_listener = NPlusOneListener()