An open source multi-tool for exploring and publishing data https://datasette.io
  • Python 86.7%
  • HTML 7.5%
  • JavaScript 4.1%
  • CSS 1.3%
  • Shell 0.2%
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Simon Willison bb59c61c9f Request-scoped permission check cache
Adds a per-request cache for permission check results, plus wiring that
resolves action permissions in bulk before plugin hooks need them:

- New _permission_check_cache contextvar, set to a fresh dict for each
  request by DatasetteRouter and reset when the request ends. Keys
  include the full serialized actor, so actors differing in any field
  (e.g. token restrictions) never share entries. SkipPermissions mode
  bypasses the cache entirely.
- datasette.allowed_many() now consults the cache and stores its
  results there, so repeated datasette.allowed() checks within one
  request resolve without further SQL.
- Table pages resolve all registered table-level actions against the
  current table and all database-level actions against its database
  (database pages likewise) in batched queries before invoking the
  table_actions/database_actions plugin hooks - allowed() calls made
  inside those hooks are then served from the cache with no plugin
  changes required. Actions with no permission rules from any plugin
  are resolved to False without touching the database.

Benchmarks (benchmarks/) with a simulated 12-plugin ecosystem making
18 checks per table page show 34 -> 13 internal-DB queries per page;
with 2ms-per-query internal DB latency (modelling Datasette Cloud)
table page time drops from 77.9ms to 27.6ms - the caching layer
accounts for ~91% of that improvement over allowed_many() alone.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-06-12 13:11:17 -07:00
.github Need is_trusted=True for the counters demo 2026-05-26 15:20:29 -07:00
datasette Request-scoped permission check cache 2026-06-12 13:11:17 -07:00
demos Fixed an unnecessary f-string 2024-02-04 10:15:21 -08:00
docs Request-scoped permission check cache 2026-06-12 13:11:17 -07:00
tests Request-scoped permission check cache 2026-06-12 13:11:17 -07:00
.coveragerc Configure code coverage, refs #841, #843 2020-06-13 13:48:23 -07:00
.dockerignore Build Dockerfile with SpatiaLite 5, refs #1249 2021-03-26 21:27:40 -07:00
.git-blame-ignore-revs Ignore Black commits in git blame, refs #1716 2022-04-22 14:58:46 -07:00
.gitattributes New explicit versioning mechanism 2020-10-28 20:38:15 -07:00
.gitignore Fix filter-input and search-input zoom on iOS Safari 2026-01-28 18:41:58 -08:00
.isort.cfg Used isort to re-order my imports 2018-05-14 00:04:23 -03:00
.prettierrc .prettierrc, refs #1166 2020-12-31 13:25:44 -08:00
.readthedocs.yaml dependency-groups and uv (#2611) 2025-12-11 17:32:58 -08:00
CODE_OF_CONDUCT.md Add code of conduct again 2022-03-15 08:38:42 -07:00
codecov.yml codecov should not be blocking 2020-07-02 21:29:32 -07:00
Dockerfile Upgrade Docker images to Python 3.11, closes #1853 2022-10-25 12:04:53 -07:00
Justfile Switch to ruff and fix all lint errors, refs #2630 2026-01-23 20:43:16 -08:00
LICENSE Initial commit 2017-10-22 17:39:03 -07:00
MANIFEST.in Include LICENSE in sdist (#1043) 2020-10-23 13:54:34 -07:00
package-lock.json Bump rollup from 3.29.5 to 3.30.0 (#2651) 2026-03-30 10:54:48 -07:00
package.json Bump rollup from 3.29.5 to 3.30.0 (#2651) 2026-03-30 10:54:48 -07:00
pyproject.toml Use asyncinject 0.7 results= seeding for per-request extras context 2026-06-11 06:42:08 -07:00
pytest.ini New allowed_resources_sql plugin hook and debug tools (#2505) 2025-10-08 14:27:51 -07:00
README.md Replace Glitch with Codespaces, closes #2488 2025-05-28 19:17:22 -07:00
ruff.toml Use ruff to upgrade Optional[x] to x | None 2025-10-26 10:50:29 -07:00
setup.cfg Switch to ruff and fix all lint errors, refs #2630 2026-01-23 20:43:16 -08:00
test-in-pyodide-with-shot-scraper.sh Introduce new /$DB/-/query endpoint, soft replaces /$DB?sql=... (#2363) 2024-07-15 10:33:51 -07:00

Datasette

PyPI Changelog Python 3.x Tests Documentation Status License docker: datasette discord

An open source multi-tool for exploring and publishing data

Datasette is a tool for exploring and publishing data. It helps people take data of any shape or size and publish that as an interactive, explorable website and accompanying API.

Datasette is aimed at data journalists, museum curators, archivists, local governments, scientists, researchers and anyone else who has data that they wish to share with the world.

Explore a demo, watch a video about the project or try it out on GitHub Codespaces.

Want to stay up-to-date with the project? Subscribe to the Datasette newsletter for tips, tricks and news on what's new in the Datasette ecosystem.

Installation

If you are on a Mac, Homebrew is the easiest way to install Datasette:

brew install datasette

You can also install it using pip or pipx:

pip install datasette

Datasette requires Python 3.8 or higher. We also have detailed installation instructions covering other options such as Docker.

Basic usage

datasette serve path/to/database.db

This will start a web server on port 8001 - visit http://localhost:8001/ to access the web interface.

serve is the default subcommand, you can omit it if you like.

Use Chrome on OS X? You can run datasette against your browser history like so:

 datasette ~/Library/Application\ Support/Google/Chrome/Default/History --nolock

Now visiting http://localhost:8001/History/downloads will show you a web interface to browse your downloads data:

Downloads table rendered by datasette

metadata.json

If you want to include licensing and source information in the generated datasette website you can do so using a JSON file that looks something like this:

{
    "title": "Five Thirty Eight",
    "license": "CC Attribution 4.0 License",
    "license_url": "http://creativecommons.org/licenses/by/4.0/",
    "source": "fivethirtyeight/data on GitHub",
    "source_url": "https://github.com/fivethirtyeight/data"
}

Save this in metadata.json and run Datasette like so:

datasette serve fivethirtyeight.db -m metadata.json

The license and source information will be displayed on the index page and in the footer. They will also be included in the JSON produced by the API.

datasette publish

If you have Heroku or Google Cloud Run configured, Datasette can deploy one or more SQLite databases to the internet with a single command:

datasette publish heroku database.db

Or:

datasette publish cloudrun database.db

This will create a docker image containing both the datasette application and the specified SQLite database files. It will then deploy that image to Heroku or Cloud Run and give you a URL to access the resulting website and API.

See Publishing data in the documentation for more details.

Datasette Lite

Datasette Lite is Datasette packaged using WebAssembly so that it runs entirely in your browser, no Python web application server required. Read more about that in the Datasette Lite documentation.