Integration Layer

Intent

Implement external integrations (Firebase, Data Connect, HTTP, SDKs) behind stable ports so the rest of the app stays framework-agnostic.

Layer Boundaries

• Only integration/infrastructure may import Firebase/AngularFire/DataConnect SDKs.
• Expose interfaces/tokens to Application; never expose platform types.

Repository Adapters

• Implement repository ports with minimal mapping:
  • DTO <-> Domain mapping happens here (or in dedicated mappers within integration).
  • Keep mapping deterministic; normalize timestamps/IDs.

Streams and Signals

• Integration may return Observables (streaming) or Promises (commands).
• Convert to signals at the Application boundary (store/facade), not in templates.
• Ensure cleanup: avoid manual subscriptions unless lifecycle-bound.

Data Connect

• Treat generated SDK as read-only output.
• After schema changes, regenerate before app code changes.
• Enforce auth directives and least-privilege queries.

Security

• Never trust client input.
• Keep secrets in env/secret manager, not in source.
• Avoid string-concatenated queries; use parameterized APIs.