APK+WebSocket source code repair and optimization list

Job ID: 40343206

Budget: $30 – $250 SGD

Fixes:

Heartbeat Mechanism: The client pings every 30 seconds, and the server pongs. Check the source code for missing heartbeats or excessively long intervals.

Reconnection After Disconnection: Implement exponential backoff (1s → 2s → 5s → 10s) to avoid overwhelming the server with a large number of instantaneous reconnections.

ACK Mechanism: Each message has a unique message_id; an ACK is sent upon receipt, otherwise the server resends the message.

Long Connection Management: Detect and clean up zombie connections to prevent memory leaks.

Message Encryption: AES/RSA + TLS; check for plaintext transmissions or hard-coded keys.

Optimization Suggestions:
Encapsulate a WebSocket client library for centralized management of all network operations.

Reconnection and heartbeat should be handled by independent coroutines/threads to avoid blocking the UI.

Support automatic reconnection upon network disconnection or network switching.

2️⃣ Data Layer

Fixes:
Offline Message Caching: Whether messages are saved after a disconnection and whether they can be recovered after reconnection.

Local Storage: Is Room/SharedPreferences secure? Are there any multi-threaded write conflicts?

Message Queue Processing: Are messages processed in order? Is there a possibility of out-of-order processing causing business logic errors?

Optimization Suggestion: Use a unified repository model to manage all data sources.

Use a unified interface for network message inbound and outbound processing.

Implement cache expiration policies and maximum message count limits to prevent memory overflow.

3️⃣ Business Layer (Domain)

Fixed Issues:
Message Parsing: Check for uncaught exceptions in JSON/Proto parsing to prevent crashes.

Authorization Verification: Are tokens or device IDs strictly validated to prevent unauthorized operations.

ACK Logic: Are any message receipts missing, leading to duplicate sending or message loss?

Optimization Suggestion: Decouple all business logic from the network layer.

Exception capture + logging to prevent the entire APK from crashing.

4️⃣ UI Layer (Presentation)

Fixed Issues:
UI directly calling the network layer → the application may experience ANR (Application Not Responding).

Stateless message updates → UI refresh errors or lag.

Optimization suggestion: Use ViewModel/LiveData or StateFlow to manage state.

Place all network or time-consuming operations in coroutines/threads.

The UI should only handle display and user interaction.

5️⃣ Security Layer

Fixed issues: Transmitting sensitive information in plaintext.

Tokens/Keys hardcoded in the source code.

The APK is not obfuscated, making it easy to decompile.

Optimization suggestion: All messages must be encrypted (TLS + AES/RSA).

Tokens/keys should not be hardcoded; they can be obtained from the server or stored securely.

Enable ProGuard/R8 obfuscation of critical classes.

6️⃣ Performance and Stability

Fixed issues: Heartbeat or message processing blocking the main thread → causing lag.

Long-connection memory leaks; APK crashes with many connections.

Server-side message loss under high concurrency.

Optimization suggestion: Handle WebSockets in a separate coroutine/thread; UI should not be blocked.

Messages are queued and processed asynchronously to prevent out-of-order delivery.

The server is configured with a limited number of connections, and Redis/Kafka is used for message caching and distribution.