CMS & Content Collections

Outcome

Map untrusted CMS entries into explicit builder inputs at one validation boundary.

Local validation — Builders reject unknown properties and expose safeParse() for external data.

Schema.org — The vocabulary defines property meaning; it does not guarantee any search appearance.

Google eligibility — Google requirements are additional and can change. Valid markup never guarantees a rich result.

Prerequisites

• A trustworthy canonical URL and baseUrl.
• Current, visible data from your domain source.
• Related builders: Article.

Recommended graph

1. Article — primary node

Minimal example

import { Article } from '@unschema-graph/core';

const entity = Article({
  "headline": "Structured data with Astro",
  "image": "/images/structured-data.jpg",
  "datePublished": "2026-09-29",
  "author": "Ada Lovelace"
});

Production pattern

Validate collection shape first, map only known fields, then call safeParse() and surface diagnostics with the entry identifier.

const result = Article.safeParse(cmsData);
if (!result.success) {
  throw new Error(result.error.issues.map((issue) => issue.message).join('\n'));
}

const graph = buildJsonLdGraph([result.data], { baseUrl: 'https://example.com' });

Environment variants

Astro	Svelte 5 / SvelteKit	Core
<Schema items={items} />	<Schema items={items} />	serializeJsonLd(buildJsonLdGraph(items))

Common errors and diagnosis

1. Spreading the complete CMS object into a strict builder. Compare the source data, safeParse() result, and JSON-LD in the built HTML.
2. Silently replacing missing required data. Compare the source data, safeParse() result, and JSON-LD in the built HTML.
3. Trusting rich text or URLs without validation. Compare the source data, safeParse() result, and JSON-LD in the built HTML.

Validation

1. Run safeParse() at the data boundary.
2. Inspect the script in built HTML.
3. Run unschema-graph audit against the output directory.
4. Schema.org / official documentation.

Final checklist

• Marked-up content is visible and current.
• Every reusable identity has a stable @id.
• Local validation and the build audit pass.
• Eligibility is understood as non-guaranteed.

Go deeper: graphs and references, validation, audit CLI.