Furst/README.md
nak0x 6dcb00da80 Add furst-read, an article extractor and minimal renderer
Fetches a page, discards everything that is not the article, and renders
what is left as a self-contained HTML document with no scripts, no
stylesheets, no webfonts and no third-party requests. The reader rule in
the starter config already points at it.

Extraction follows Readability: score p/pre/td/blockquote by prose weight,
propagate to ancestors with decay, adjust by class and id names, scale by
one minus link density, then take the winner plus sibling nodes that also
read like body copy. Serialisation runs against a tag whitelist, with
unlisted elements contributing their children but no tag of their own, so
wrapper divs disappear.

Handling for what real pages actually do:

- follow meta http-equiv=refresh stubs, including inside noscript
- fall back to data-src when src holds a lazy-load placeholder
- take the first srcset candidate, the smallest, not the last
- decode via Content-Type charset, then meta charset, then UTF-8
- resolve links against the post-redirect URL so file:// output works
- ignore script and style text so a page cannot inflate its own score

Output goes to a cache file named by a hash of the URL and opens in
$FURST_BROWSER, $BROWSER, or the first light browser on $PATH; --html,
--text, --out and --stdin cover the other uses.

Restructures the repository as a workspace so the router keeps its two
dependencies and its fast build.
2026-09-06 19:35:30 +02:00

3.5 KiB
Raw Blame History

furst

A URL router. It sits where your default browser used to, and sends each URL to the cheapest tool that can actually handle it — mpv for video, a pager for PDFs, a light WebKit browser for reading, and Firefox only when nothing else will do.

Built for a Core2 Duo with 4GB of RAM, where the browser is the problem.

Why

A news page is 25MB across 80+ requests with 13MB of JavaScript to parse and JIT. The same article extracted is ~20KB. Choosing a lighter engine buys 23×; not loading the payload at all buys 10100×. furst is the dispatcher that decides which of those you get, per URL.

Install

cargo build --release
install -Dm755 target/release/furst ~/.local/bin/furst

furst --init      # writes ~/.config/furst/rules.toml, probes for a light browser
furst --install   # registers furst as the system default browser

--install writes ~/.local/share/applications/furst.desktop and points xdg-settings at it, so every link click in every application routes here.

Use

furst <url>              # match a rule and exec its command
furst --explain <url>    # show what would run, and why; run nothing
furst --list             # show the loaded rules

--explain is the one you want when a URL goes somewhere surprising:

$ furst --explain https://youtu.be/abc123
scheme  https
host    youtu.be
path    /abc123

-> [video] mpv --ytdl-format=bestvideo[vcodec^=avc1][height<=?720]+... https://youtu.be/abc123
   [default] surf https://youtu.be/abc123

Rules

~/.config/furst/rules.toml. First matching rule wins. If its command is missing from $PATH, furst falls through to the next matching rule, and finally to default — which is what lets you name tools you have not written yet and have the config stay working today.

default = ["surf", "{url}"]

[[rule]]
name = "video"
hosts = ["youtube.com", "youtu.be"]
run = ["mpv", "--ytdl-format=bestvideo[vcodec^=avc1][height<=?720]+bestaudio/best", "{url}"]

[[rule]]
name = "hn"
hosts = ["news.ycombinator.com"]
terminal = true                      # wrap in $TERMINAL -e
run = ["furst-hn", "{url}"]

A rule matches when every criterion it states is satisfied; a criterion is satisfied by any one of its patterns. A rule that states nothing matches everything.

Key Matches against
schemes https, mailto, magnet, …
hosts example.com = apex and every subdomain; *.example.com = same; =example.com = that host exactly; * = any
paths path component only, glob with *, case-insensitive
contains substring of the whole raw URL
Placeholder
{url} {url_enc} the URL, raw or percent-encoded
{host} {path} {scheme} parsed components

If no argument mentions {url} or {url_enc}, the URL is appended last.

Notes for old hardware

  • Force H.264 for video. A Core2 handles 720p avc1 in software but stalls on VP9/AV1, which is what YouTube serves by default. That format string is doing more work than the resolution cap.
  • Host matching strips userinfo with rfind('@'), so https://bank.example@evil.example/ routes on evil.example.
  • furst execs the handler rather than forking, so it leaves no process behind.

Companion tools

  • furst-read — fetch a page, extract the article, and render it as minimal HTML with no scripts, stylesheets, or webfonts. The reader rule in the starter config points at it.

License

MIT