[5.4 Web App] Sync with Backend

[fIyingPhoenix]

Milestone: Milestone 5: Infrastructure & Tools
Category: 5.4 Web App
Task: Implement sync functionality to ensure that meal data logged via the Blazor client is synchronized with the backend API.

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Description

This task involves implementing synchronization between the Blazor web app (client-side) and the Python backend. Users should be able to log their meals on the Blazor client, and these meals must be successfully synced with the backend when the client is online. Additionally, offline logging and conflict resolution should be considered to ensure data integrity.

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Subtasks:

• Implement synchronization logic:
  • Develop a sync service that sends new meal data from the client to the backend API
  • Ensure that meals logged when offline are stored locally and synced when the client goes online
  • Implement periodic sync for any new data
• Handle sync conflicts:
  • Implement logic to resolve conflicts when data has been modified both locally and remotely
  • Use timestamps or versioning to identify the latest changes for each meal
  • Provide feedback to users when a conflict occurs (e.g., ask user to choose which version to keep)
• Implement meal syncing endpoint:
  • Create a GET endpoint in the backend to fetch unsynced meal data for the client
  • Create a POST endpoint in the backend to send new meal data from the client
• Offline handling:
  • Store meal data in local storage or SQLite on the client when the app is offline
  • Queue meal data to be synced as soon as the app regains internet connectivity
• Error handling:
  • Implement error handling for failed sync attempts (e.g., retry mechanism or user notifications)
  • Provide meaningful feedback for the user in case of sync failures (e.g., "Sync failed, please check your internet connection")
• Testing sync functionality:
  • Test syncing with both new and existing meal data
  • Verify sync behavior when switching between offline and online states
  • Test edge cases, such as syncing multiple devices or conflicting updates
• Documentation:
  • Document the sync process and its implementation in the README or user manual
  • Include information on troubleshooting sync issues

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Technical Considerations:

• Use RESTful API calls to sync meal data between the client and backend
• Implement an offline-first strategy using local storage or SQLite for meal data when the client is offline
• Handle API request retries for scenarios where the sync fails due to network issues
• Ensure that meal data is stored and synced correctly, even in the event of app crashes or forced closures

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Acceptance Criteria:

• Meals logged on the Blazor web client are synced with the backend API
• Offline meal logging works, and meals are synced once the client is online again
• Conflict resolution works as expected (users can choose which version to keep)
• Sync errors are handled gracefully, and users are notified when issues occur
• Sync functionality is tested and documented