Print Logs

Using print statements is fine when you are building small apps, but as your app grows you will require more complex logging solutions.

How it works

The project is using the logging package from the Dart team.

There is a LoggingAbstraction that only creates logs in the development environment (keeping production logs free). But you can extend it for production with third party solution(s).

Use the Logger

To create a log within a viewmodel it would look like this:

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class HomeViewModel {
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  final _logger = Logger('$HomeViewModel')
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  void createTodo() {
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    // logic for creating a todo
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    _logger.info('Todo created successfully');
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  }
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}

Development

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INFO: HomeViewModel: Todo created successfully

Production (no local prints)

Extensibility

The LoggingAbstraction is fully extendable through callback functions. You can pass in custom logging handlers for production environments, such as remote logging services.

Using with Remote Logging

In your startup view model, you can initialize logging with custom callbacks for remote logging services:

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Future<void> initializeApp() async {
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  appStateNotifier.value = const InitializingApp();
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  try {
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    locator.registerMany(modules);
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    // Initialize logging with optional remote logging callbacks
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    loggingSubscription = _loggingAbstraction.initializeLogging(
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      onLogs: [
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        (record) => sendToSentry(record),
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        (record) => sendToGrafana(record),
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        // Add more remote logging services as needed
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      ],
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    );
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    appStateNotifier.value = const AppInitialized();
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  } catch (e, st) {
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    appStateNotifier.value = AppInitializationError(e, st);
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  }
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}