examples

Examples

The same program in all three languages: capture a site at every App Store and Google Play size, write each store to its own folder, exit non-zero if anything is off-size or failed.

Every example here was run against a live site before being committed. They are checked in CI, so they cannot silently rot.

44 exact, 0 problem(s)
  apple/  33 PNGs
  play/   11 PNGs

	run it
Node	npm i && node shots.js https://example.com ./shots
Python	pip install proofsheet && python shots.py https://example.com ./shots
Rust	cargo run --release -- https://example.com ./shots

Any URL works, including a dev server — http://localhost:3000 is a normal target.

The one thing worth copying

Checking the output size is not enough:

!capture.environment.viewportHonoured   // Node
not capture.environment.viewport_honoured   # Python
!capture.environment.viewport_honoured  // Rust

A page can be captured at exactly the pixel count a store demands and still show completely the wrong thing. If the site serves a desktop layout and declares <meta name="viewport" content="width=1120">, Chrome honours that meta tag, lays the page out at 1120 CSS px, and scales the desktop design down into a phone-sized frame. The file is 1320x2868 and passes every dimension check. It is still a desktop screenshot.

Measured on a real site, changing only the User-Agent and touch points:

	metrics only	+ UA + touch
innerWidth	1120	440
maxTouchPoints	0	5
meta viewport	width=1120	width=device-width

So assert on the environment, not just the dimensions. Each example prints a warning when a page overrides the layout viewport.

The second thing

Branch on ok, never on failed == 0:

if report.ok:      # right
if not report.failed:   # wrong -- also true when NOTHING was captured

A run that captured zero images has zero failures. ok additionally requires that at least one capture actually happened.

Determinism

All three pass seed=42. The same seed against unchanged content reproduces byte-identical PNGs, which is what makes a regenerated screenshot set diffable — you can commit them and review changes as a diff.

Browser

No browser on the machine? The CLI fetches a pinned one (the Node and Python packages are libraries and ship no executable):

cargo install proofsheet && proofsheet install-browser

It lands in ~/.proofsheet/browser (PROOFSHEET_HOME overrides) and all three examples find it with no configuration — none of them sets a browser path. To use one you already have:

export PROOFSHEET_CHROME=/path/to/chrome

Empty means unset, so export PROOFSHEET_CHROME=$(which chrome) falls back to discovery on a machine without it rather than failing.