Data Contract

Kind: constraint

Layer: Contracts Core

Record: architecture:data-contract

Severity: mandatory

Scope: data, message, persistence, integration

Canonical: Ontology

A rule or precondition that data exchanged between parties has declared fields, types, nullability and meaning.

Listed in Architecture principles, after Service Contract and before Schema Contract.

Requires

• Schema
• Type Safety
• Semantic Consistency

Reinforces

• Interoperability
• Data Quality

Enables

• Schema Evolution

Conflicts with

• Schema Drift

In tension with

• Flexible Ingestion

Tensions

• Data Contract / Flexible Ingestion

Violated by

• Untyped Payloads
• Null Semantics Drift

Refactored by

• Introduce Boundary DTO
• Schema Validation
• Canonical Data Model

Severity

• mandatory

Category

• Contracts / Interfaces / Compatibility

Reinforced by

• Schema Contract

Linked from

• Anti-patterns
• Contracts / Interfaces / Compatibility
• Schema / Canonical Data / Semantics
• Contracts / Interfaces / Compatibility
• Core Vocabulary
• Schema / Canonical Data / Semantics
• Severity levels
• The resolutions