Project 02: Schema Knowledge Graph Repair

Objective

Repair a fragmented JSON-LD graph into a connected Schema.org @graph: Google's required properties present, every entity identified by an @id, and zero dangling references.

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Step 1: Inspect the Broken Graph

Open projects/project-02-schema-knowledge-graph/starter/broken-schema.json.

Notice the issues:

• The Product and the Article have no @id, so nothing can reference them.
• The Product offer is missing priceCurrency (required for Google merchant listings).
• The Article references an @id node #unknown-author that does not exist in the graph.

Run the validator:

node tools/schema-graph-validator.js projects/project-02-schema-knowledge-graph/starter/broken-schema.json

Output:

JSON-LD blocks: 1 | Indexed Entities: 0
Warnings:
  - [Product -> Offer] Missing 'priceCurrency' (e.g. USD, EUR): required for Google merchant listings
Errors:
  - [Product] Missing '@id' required by the harness for every @graph entity
  - [Article] Missing '@id' required by the harness for every @graph entity
  - Dangling @id reference: '#unknown-author' is referenced, but no entity with that @id is defined on this page.

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Step 2: Verify the Repaired Knowledge Graph

Open projects/project-02-schema-knowledge-graph/solution/connected-knowledge-graph.json.

Run the validator:

node tools/schema-graph-validator.js projects/project-02-schema-knowledge-graph/solution/connected-knowledge-graph.json

Output:

JSON-LD blocks: 1 | Indexed Entities: 4
✔ Schema JSON-LD validation PASSED!