Masamune Scheduler

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Masamune Scheduler

Usage

Installation

Add the package to your project.

flutter pub add masamune_scheduler

Run flutter pub get when editing pubspec.yaml manually.

Register the Adapter

Configure scheduler queries alongside other Masamune adapters. The scheduler works with Functions to copy or delete documents on a schedule.

// lib/adapter.dart

/// Masamune adapters used by the application.
final masamuneAdapters = <MasamuneAdapter>[
  const UniversalMasamuneAdapter(),
  const FunctionsMasamuneAdapter(),
  const ModelAdapter(),
  const SchedulerMasamuneAdapter(),
];

Ensure you have set up Masamune Models for your app because scheduler queries operate on them.

Define Schedules

Use the provided schedule models to set up copy/delete operations triggered by server commands.

Copy Document Schedule:

class ScheduledPostPage extends PageScopedWidget {
  @override
  Widget build(BuildContext context, PageRef ref) {
    return ElevatedButton(
      onPressed: () async {
        // Schedule a document copy (e.g., publish draft at specific time)
        final schedule = ref.app.model(
          ModelCopyDocumentSchedule.collection(),
        ).create();
        
        await schedule.save(
          ModelCopyDocumentSchedule(
            sourceCollectionPath: "posts",
            sourceDocumentId: "draft_123",
            targetCollectionPath: "posts",
            targetDocumentId: "published_123",
            executeAt: DateTime.now().add(const Duration(hours: 1)),
          ),
        );
        
        print("Scheduled to publish in 1 hour");
      },
      child: const Text("Schedule Post"),
    );
  }
}

Delete Documents Schedule:

// Schedule deletion of old logs
final deleteScheduleCollection = ref.app.model(
  ModelDeleteDocumentsSchedule.collection(),
);

final deleteSchedule = deleteScheduleCollection.create();
await deleteSchedule.save(
  ModelDeleteDocumentsSchedule(
    collectionPath: "logs",
    field: "createdAt",
    endAt: DateTime.now().subtract(const Duration(days: 30)),  // Delete logs older than 30 days
  ),
);

Backend Implementation

Your Cloud Functions should periodically check for pending schedules and execute them:

Scheduled Function Example:

// Cloud Functions (runs every 5 minutes)
export const processSchedules = functions.pubsub
  .schedule('every 5 minutes')
  .onRun(async (context) => {
    const now = admin.firestore.Timestamp.now();
    
    // Find pending copy schedules
    const copySchedules = await admin.firestore()
      .collection('model_copy_document_schedule')
      .where('executeAt', '<=', now)
      .where('executed', '==', false)
      .get();
    
    for (const doc of copySchedules.docs) {
      const schedule = doc.data();
      
      // Copy document
      const sourceDoc = await admin.firestore()
        .collection(schedule.sourceCollectionPath)
        .doc(schedule.sourceDocumentId)
        .get();
      
      if (sourceDoc.exists) {
        await admin.firestore()
          .collection(schedule.targetCollectionPath)
          .doc(schedule.targetDocumentId)
          .set(sourceDoc.data());
      }
      
      // Mark as executed
      await doc.ref.update({ executed: true });
    }
    
    // Process delete schedules similarly...
  });

Alternative: Server Command Pattern:

// Client creates a command for the server to process
final command = ModelServerCommandCopyDocumentSchedule(
  scheduleId: copySchedule.id,
);
await command.save();

Your backend queries pending commands and executes them.

Tips

• Combine with katana_cli generated models to ensure type safety.
• Store schedule metadata in Firestore/Database for auditing.
• Implement retries and error logging in your Functions to handle transient failures.
• Use server timestamps (FieldValue.serverTimestamp()) for consistent scheduling across time zones.

GitHub Sponsors

Sponsors are always welcome. Thank you for your support!

https://github.com/sponsors/mathrunet