android-networking

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name: android-networking description: Android networking — Retrofit, OkHttp, Ktor, caching, error handling, resilience. user-invocable: true

Android Networking

Cross-cutting skill — always activates alongside the project-type-specific skill.

Hard Rules

• Use Retrofit (Android-only) or Ktor (KMP) as the HTTP client — not raw HttpURLConnection.
• Define API interfaces with suspend functions — no blocking calls.
• Handle all HTTP error codes explicitly — do not swallow non-2xx responses.
• Use OkHttp interceptors for cross-cutting concerns (auth, logging, headers).
• Never log request/response bodies in production — sensitive data exposure risk.
• Set connect, read, and write timeouts explicitly — do not rely on defaults.
• Use kotlinx.serialization or Moshi for JSON — not Gson (reflection-based, slower).
• All network calls must happen off the main thread.
• Use HTTPS for all endpoints — no cleartext traffic.
• Implement token refresh in OkHttp Authenticator — not in individual API calls.

Core Patterns

• Single OkHttpClient instance shared across Retrofit services.
• Logging interceptor for debug builds only (HttpLoggingInterceptor.Level.BODY).
• Auth interceptor adds Bearer token; Authenticator handles 401 refresh.
• Wrap API responses in Result or sealed class for error propagation.
• Use @Headers for static headers, @Header for dynamic per-request headers.
• Repository layer transforms API DTOs to domain models.

References

• references/retrofit_setup.md
• references/okhttp_interceptors.md
• references/error_handling.md
• references/caching.md
• references/ktor_multiplatform.md
• references/advanced_patterns.md
• references/testing.md