Data Contracts — Formal Agreements on Data Quality and Structure

Data contracts are formal agreements between data producers and consumers. Schema, quality, SLA and evolution rules — like API contract for data.

Why Data Contracts¶

Without contracts, upstream changes schema and breaks downstream pipeline.

# orders-contract.yml
apiVersion: v1
kind: DataContract
metadata:
  name: orders-events
  version: "1.2.0"
  owner: orders-team
schema:
  fields:
    - name: order_id
      type: string
      required: true
    - name: total_czk
      type: decimal
      constraints:
        - type: range
          min: 0
quality:
  freshness: "< 1 hour"
  completeness: "> 99.5%"
sla:
  availability: "99.9%"
evolution:
  breaking_changes: "major version + 30 day deprecation"

In Practice¶

• Semantic versioning
• CI/CD validation
• Deprecation period
• Continuous SLA monitoring

Summary¶

Data contracts prevent breaking changes and ensure quality of data interfaces.