DeckSpec

DeckSpec is a deterministic TypeScript toolkit for building QA-checked PPTX decks from strict JSON source files.

deck.source.json
  -> normalized JSON with concrete geometry/styles
  -> layout-report.json
  -> PPTX
  -> optional PDF/PNG/contact-sheet render QA

Install

npm install deckspec

Local development:

npm install
npm run verify:release

CLI

deckspec validate examples/framework-smoke/deck.source.json
deckspec normalize examples/framework-smoke/deck.source.json --out dist/example/deck.normalized.json
deckspec qa dist/example/deck.normalized.json --out dist/example/layout-report.json
deckspec build dist/example/deck.normalized.json --out dist/example/deck.pptx
deckspec render dist/example/deck.pptx --outDir render/example
deckspec smoke examples/framework-smoke/deck.source.json --render

During local development, replace deckspec with tsx src/cli.ts.

Source format

The supported authoring contract is *.deck.source.json. Narrative notes, planning docs, or Markdown drafts can live beside a deck, but DeckSpec does not compile Markdown into decks.

Deck elements include text, shapes, lines, images, image-in-shape masks, tables, charts, and media. Use type: "imageShape" when an image should fill a native PowerPoint shape while preserving shape line/rounding:

{
  "id": "photo-frame",
  "type": "imageShape",
  "shape": "roundRect",
  "imagePath": "assets/photo.png",
  "x": 1040,
  "y": 140,
  "w": 560,
  "h": 360,
  "sizing": { "type": "cover", "w": 560, "h": 360 },
  "rectRadius": 0.25,
  "line": { "color": "34D399", "width": 2.25 }
}

The current imageShape implementation supports PowerPoint native preset shapes with picture fill, line styling, and rectRadius where applicable. Common verified presets include rect, roundRect, ellipse, triangle, diamond, pentagon, hexagon, star5, heart, cloud, and trapezoid. Use ellipse for oval/circle masks; circle is accepted as an alias that emits an ellipse preset, with equal w/h producing a circle. sizing.type is translated into native DrawingML crop/fill rectangles for image-in-shape masks: cover emits <a:srcRect> crop percentages, crop maps an explicit source-pixel crop box to <a:srcRect>, and contain emits <a:fillRect> padding. Custom geometry supports normalized polygon points, richer paths with moveTo, lineTo, quadBezTo, cubicBezTo, arcTo, and close commands, plus rawXml passthrough for a complete imported <a:custGeom> block when exact reference PPTX geometry is required.

See:

• examples/framework-smoke/deck.source.json for a minimal deck.
• examples/feature-gallery/deck.source.json for the supported PptxGenJS surface.
• schemas/deck.schema.json for the source contract.
• docs/versioning.md for schema IDs, SemVer, and release policy.

Schema IDs and versioning

DeckSpec publishes versioned JSON Schema IDs from immutable Git tags. For 0.2.0, the deck schema ID is:

https://raw.githubusercontent.com/leehack/deckspec/v0.2.0/schemas/deck.schema.json

Use the package version as the schema version. Patch releases may clarify validation without changing accepted source shape; minor releases may add backwards-compatible schema fields; major releases are reserved for breaking source-schema or CLI/API changes. See docs/versioning.md.

Publishing

This repo is prepared for npm publishing but does not publish during normal CI. Maintainers should run:

npm run verify:release
npm run publish:dry

Then publish from the GitHub Actions Publish to npm workflow or run npm publish --access public with a clean, tagged release checkout.

Built-in layout catalog

The default hybrid-keynote template includes:

cover
section-break
split-hero
three-card-row
comparison
timeline
code-walkthrough
data-viz
diagram
quote
metric-grid
image-hero
closing-qr

Quality gates

DeckSpec uses Prettier for formatting and type-aware strict ESLint for code quality. ESLint is configured with typescript-eslint strictTypeChecked + stylisticTypeChecked, projectService: true, and eslint-config-prettier to avoid formatting-rule conflicts.

npm run format:check
npm run lint
npm run typecheck
npm run coverage
npm run verify:release

Use npm run format and npm run lint:fix for local cleanup before running the gates.

verify:release runs formatting, lint, typecheck, coverage, build, rendered smoke decks, and npm pack --dry-run.

Render prerequisites

Render QA uses command-line tools when --render is enabled:

• LibreOffice soffice for PPTX → PDF
• Poppler pdftoppm for PDF → PNG

If those are unavailable, smoke without --render still validates, normalizes, QA-checks, builds, and verifies PPTX structure.