fast-querydict 0.1.0

Fast application/x-www-form-urlencoded parser for Django QueryDict, with optional html-json-forms nesting, in one pass

fast-querydict

A fast, entity-agnostic parser for application/x-www-form-urlencoded request bodies, built for Django. One pass over the raw bytes yields both the flat data (ready to become a real django.http.QueryDict) and, optionally, the generic html-json-forms nesting of the same body.

import fast_querydict

grouped, nested = fast_querydict.parse(request.body, build_json=True)
# grouped -> {"units": ["a", "b"], "id": ["9"], ...}   raw, first-seen order
# nested  -> {"units": [{"capacity": "100"}], "id": "9", ...}  or None

• grouped is {key: [value, ...]} with raw values (percent- and +-decoded, not trimmed) in first-seen key order — exactly the internal storage of a QueryDict, so Python can adopt it with a single dict.update.
• nested is the html-json-forms nesting (a[0][b] → {"a": [{"b": …}]}), with single scalar values trimmed and "" nulled, or None when build_json is false.

See projects/fast_post.py in the GEM project DB for the Django glue: a QueryDict subclass carrying .json, and a pre-CSRF middleware that builds it lazily on first request.POST access.

Build / develop

cd fast_querydict
cargo test                 # pure-Rust logic tests (no Python needed)
maturin develop --release  # build + install into the active venv

The Python side imports it opportunistically and falls back to Django's own parser if it is missing or fails to import, so it is safe to ship without it.

Publish

Wheels are built and uploaded to PyPI by the publish-fast-querydict GitHub Actions workflow (manylinux wheels + sdist via PyO3/maturin-action, uploaded with maturin upload — the same approach as jsonlinesrust/flatterer). It is manual / click-to-deploy: Actions → publish-fast-querydict → Run workflow.

One-time setup: add a PyPI API token as the repo secret PYPI_API_TOKEN. Bump version in Cargo.toml before publishing a new release.

Consumers then install the prebuilt wheel — no Rust toolchain needed at deploy:

pip install fast-querydict