An open source multi-tool for exploring and publishing data https://datasette.io
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Alex Garcia ba3756eb54 Move the serve-subprocess test plumbing into a conftest fixture
The two new tests span a datasette serve subprocess by hand: each found a
free port with a copy of test_playwright.py's find_free_port, built its own
subprocess.Popen call, polled with its own 15 second deadline loop, and
tore the process down in its own finally block. That is the third and
fourth hand-rolled copy of plumbing conftest.py already owns for
ds_localhost_http_server and ds_unix_domain_socket_server.

Move find_free_port into conftest.py and add a serve_with_plugins factory
fixture that writes plugin sources to a temporary --plugins-dir, takes a
free port, waits for the server to answer, and terminates every process it
started when the test ends. wait_until_responds() grows an optional
process argument so a server that dies during startup fails immediately
with its captured output instead of waiting out the timeout, and now
catches httpx.TransportError rather than only httpx.ConnectError - a
superclass, so existing callers are unaffected.

Two fixes beyond the deduplication:

The marker test polls until its flag flips, which meant it would also have
passed if the startup hook were re-run on the serving loop by the
first-request fallback - the exact bug it exists to catch. That cannot
happen while invoke_startup() is idempotent, but nothing said so. The
plugin now counts startup calls and the test asserts it ran exactly once,
so removing that guard fails the test loudly instead of quietly turning it
into a no-op.

test_startup_error_fails_fast_before_port_binds passes on unmodified main,
where startup already ran ahead of uvicorn.run(), so it is a
characterization test rather than a regression test for this commit; its
docstring now says so. Its loop re-checking that nothing was listening ran
about one iteration before the process exited, and could not distinguish a
pre-bind failure from a port nothing ever touched, so it is replaced by a
single check with a comment about what it does and does not prove.

Verified the red side is preserved: the marker test still fails on
unmodified main, now in 3.7s rather than 15.2s.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-31 13:13:03 -07:00
.github Bump a whole lot of GitHub Actions versions 2026-07-07 14:40:33 -07:00
datasette Run datasette serve startup and uvicorn on a single event loop 2026-08-31 13:13:03 -07:00
demos Fixed an unnecessary f-string 2024-02-04 10:15:21 -08:00
docs Release 1.0a38 2026-08-06 11:20:25 -07:00
tests Move the serve-subprocess test plumbing into a conftest fixture 2026-08-31 13:13:03 -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 Ignore ignored/ directory 2026-06-25 21:20:29 -07:00
.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 Add Prettier check to lint recipe (#2821) 2026-07-03 09:50:35 -07:00
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 Run datasette serve startup and uvicorn on a single event loop 2026-08-31 13:13:03 -07:00
pytest.ini Initial Playwright setup plus first test 2026-06-14 16:39:55 -07:00
README.md Replace Glitch with Codespaces, closes #2488 2025-05-28 19:17:22 -07:00
ruff.toml Upgrade to ruff>=0.16.0 (#2857) 2026-07-25 15:47:08 -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 Test against pyodide/v314.0.0 2026-06-22 10:11:56 -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.