Networking with Dio

• Use Dio as the primary HTTP client package.
• Use type-safe model classes with

  fromJson

  /

  toJson

  factories for all request/response bodies.
• Handle all HTTP status codes appropriately with typed exceptions (e.g.,

  ServerException

  ,

  NetworkException

  ,

  UnauthorizedException

  ).
• Use proper request timeouts (

  connectTimeout

  ,

  receiveTimeout

  ,

  sendTimeout

  ).

Dio Interceptors

• Use interceptors for cross-cutting concerns:
  • Auth Interceptor: Attach access tokens to headers, handle token refresh on 401.
  • Logging Interceptor: Log requests/responses in debug mode via

    AppLogger

    .
  • Error Interceptor: Transform

    DioException

    into domain-specific

    Failure

    types.
• Register interceptors centrally via

  injectable

  for consistent behavior across all API calls.

Repository Pattern

• DataSources contain only raw Dio API calls — no business logic or mapping
• Repositories orchestrate between remote DataSources and local cache for network data

Retry & Resilience

• Implement retry logic with exponential backoff for transient failures (e.g., 500, timeout).
• Set a maximum retry count (default: 3 retries).
• Cache responses when appropriate to reduce network calls and improve offline UX.

Performance

• Parse JSON in background isolates for large responses (> 1MB) using

  compute()

• Do NOT block the UI thread with synchronous network operations

Security

• Store tokens via

  flutter_secure_storage

  — never in source code or

  SharedPreferences

• All API communication MUST use HTTPS