index.html, the stylesheets and the entry bundles are all served from fixed
URLs and answered with `public, max-age=31536000, immutable`. Nothing in
those URLs changes when the bytes behind them do, and immutable tells the
browser not to ask, so a client that visited once could go on running the
page it downloaded then — for a year, with the build-stamped ETag never
consulted. That is how a layout fix ships and one browser still shows the
old behaviour while every other one has it: not a rendering difference, a
copy of last week's stylesheet.
Only the shared chunks are content-addressed — esbuild hashes their names —
so only they can be kept forever. Everything served from a stable URL now
answers `no-cache`, which asks and gets a 304 in the ordinary case, at the
cost of one conditional request per asset per load. Vendored files with a
version in the URL stay immutable; Leaflet, whose URL does not name its
version, revalidates with the rest.
Covered both ways: a unit test on the policy each asset gets, and endpoint
tests that the page, the stylesheet and app.js come back revalidating with an
ETag, and that an unchanged one answers 304 under the same policy.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SyX26FCpMQxiBoC7r5K1A7
Signed-off-by: Stan Grams <sjg@haxx.space>
sjgandClaude Opus 5