plating

Reproducible, sanitized terminal-demo SVGs for READMEs and websites.

That recording was made by plating: plating render examples/plating-demo.json.

What it does

You want a clean terminal recording at the top of your README, the kind that types a command and shows real output in a tidy macOS-style window. Recording one by hand means fighting a screen recorder, leaking your home path and hostname into the frames, and redoing it whenever the output changes. plating turns a small JSON spec into that SVG, every time, from real command output, with a leak scan in front of it.

• Reproducible. Commit the spec and its captured output; regenerate the exact SVG with one command.
• Sanitized. A built-in leak scan refuses to render if a home path, username, hostname, or private IP slips into the frame.
• Honest. Commands and their output are verbatim. Only the typing animation and a throwaway-path to ~ rewrite are synthesized.
• Portable. The animated SVG embeds in GitHub READMEs and on web pages as a plain <img>, with no runtime JavaScript.

Install

pipx install plating-cli
npm install -g svg-term-cli   # the SVG renderer plating shells out to

Use it

Write a spec, quickstart.json:

{
  "title": "quickstart",
  "width": 84,
  "steps": [
    { "command": "mytool --version", "output": "mytool 1.2.3\n" },
    { "command": "mytool build", "output_file": "build-output.txt" }
  ]
}

Render it:

plating render quickstart.json
# wrote quickstart.svg   (and quickstart.cast, the reproducible source)

Then embed quickstart.svg in your README or drop it into a site.

Where each step's output comes from

In priority order:

In the step	Output is
"output": "..."	the literal string
"output_file": "path"	a captured-output file (relative to the spec)
"run": true (or plating render --run)	the live result of running command

Live capture (--run) is convenient; committing captured output is what makes it reproducible in CI. Use normalize to rewrite a throwaway path into something clean:

{ "normalize": [["/tmp/tmp.AbC123/demo", "~/my-repo"]] }

Sanitization

Before rendering, plating scans the recording for /home/... and /Users/... paths, the machine's current username and hostname, and private IPs. If it finds one it refuses to render and tells you how to fix it (add a normalize rule, or pass --allow-leaks). You can scan any file on its own:

plating scan some-recording.cast

Options

Spec keys: title, width, height, padding, window (macOS chrome, on by default), prompt, prompt_color, the timing knobs (type_speed, line_delay, command_pause, ... see src/plating/cast.py), normalize, scan_patterns, cwd.

CLI:

plating render <spec> [--run] [--cwd DIR] [--out-dir DIR] [--png MS] [--allow-leaks]
plating scan <file>

--png MS writes a static PNG of the frame at MS milliseconds (via headless Chrome), handy for a quick eyeball before you commit the SVG.

A real example

examples/brigade-quickstart.json rebuilds the quickstart recording used in the Brigade README from its real, captured output:

plating render examples/brigade-quickstart.json

License

MIT. See LICENSE.