@orrery-diagrams/core

The Orrery model: the JSON Schema, the validator, a moment of the model, view scoping, packs, shapes and the SVG renderer. Everything the orrery command does is a call into this package, and it runs in Node 22+ and in a browser. The model is specified in docs/MODEL.md.

npm install @orrery-diagrams/core @orrery-diagrams/layout-elk

import { validate, render, renderDocument, renderExport } from "@orrery-diagrams/core";
import { ElkLayoutEngine } from "@orrery-diagrams/layout-elk";

const r = validate(JSON.parse(await readFile("app.orrery.json", "utf8")));
if (!r.ok) for (const e of r.errors) console.error(e.toString()); // "/components/2/kind: unknown kind ..."
else {
  const still = await render(r.model, new ElkLayoutEngine(), { view: "overview", scenario: "db-fails", step: 1 });
  const interactive = await renderDocument(r.model, new ElkLayoutEngine(), { runtime: RUNTIME_SOURCE }); // from @orrery-diagrams/runtime
  for (const x of r.model.exports) await writeFile(`${x.id}.svg`, await renderExport(r.model, new ElkLayoutEngine(), x));
}

The public API

The root export is the whole of what semver covers, and a test pins the list:

| Export | What | |---|---| | the model's types | Model, Component, Connection, Group, View, Scenario, Export, Pack, ... | | validate(input, { packs? }) | The schema, then every rule of the specification, with pointer-addressed errors and warnings; returns the normalised model. packs hands over vocabularies in code, for a browser or a bundler. | | schema | The JSON Schema, as an object. | | declare(model, { scenario?, step?, set? }) | One moment of the model: the states, reasons and loads a scenario step or a what-if declares, applied. | | render, renderDocument, renderExport | A still of one view, the interactive file with every view and drill-down embedded, or one entry of the model's exports. | | loadPack, packNames, packProblem, installHint, PROVIDER_PACKS | The vocabulary packs: sre is built in; the providers' icon packs are their own packages under the providers' terms. | | sanitizeGlyph | A custom icon's markup, rebuilt from an allowlist of drawing elements and attributes. | | LayoutEngine, LayoutGraph, LayoutResult | The contract a layout engine implements: a graph of measured boxes in, positions and routes out. | | ModelError, ValidationError, ValidationWarning | What the calls throw or return. |

Two more entry points exist and are not promised by semver:

• @orrery-diagrams/core/internal (and /internal/<module>): the renderer's parts, for the runtime, the raster and the tools: defaults, measurement, view scoping, flow timing, looks, shapes, the sequence layout.
• @orrery-diagrams/core/testing: FakeLayoutEngine, a layout engine that lays out without ELK, for tests.

Packs

A model says "kinds": { "use": ["aws"] } and names kinds like aws:s3. The aws, azure and gcp packs are separate packages, @orrery-diagrams/pack-aws and so on, because the icons are the providers' and come under their terms rather than this package's MIT licence; installing one is accepting those terms. A missing pack fails validation naming the package to add. See docs/PACKS.md.

Licence

MIT. The provider icon packs are not part of this package.