tasks/D9_schema_validation/spec.md

D9: JSON Schema Validation Pipeline

Goal

Fix a JSON data pipeline (pipeline.py) that validates incoming records against a schema. The pipeline has 3 schema validation bugs and 2 type coercion bugs.

Hard Requirements

Schema Validation Bugs

1. Missing required field check: The validator does not reject records missing the email field — it should.
2. Wrong type check for age: The validator accepts string ages like "25" — it must require integer type.
3. Enum validation broken: The status field should only accept ["active", "inactive", "pending"] but the check is case-sensitive and rejects "Active". Fix: normalize to lowercase before checking.

Type Coercion Bugs

4. Timestamp coercion: The created_at field is a Unix timestamp (integer) but the output serializer writes it as a string. Fix: keep as integer in output JSON.
5. Boolean coercion: The verified field accepts "true"/"false" strings but should coerce them to actual JSON booleans in the output.

Pipeline

• Input: data/input/records.json (array of objects)
• Schema: data/schema.json
• Valid output: data/output/valid.json
• Invalid output: data/output/invalid.json (with rejection reasons)
• Run: python pipeline.py

Deliverables

• Fixed pipeline.py
• Correct output files
• Verifier confirms all 5 bugs fixed.