Cursor rule

1---
2globs: *.astro
3description: Astro D1 database integration patterns and best practices
4---
5 
6# Astro D1 Database Integration
7 
8## Database Access Pattern
9 
10Always follow this pattern for accessing D1 database in Astro components:
11 
12```astro
13---
14import { DatabaseService } from '../services/database_service';
15 
16// Standard D1 database access pattern
17const db = (Astro.locals.runtime?.env?.DB as D1Database) || null;
18 
19let data: { results: any[]; error?: string } = { results: [] };
20 
21if (db) {
22  try {
23    const dbService = DatabaseService.getInstance(db);
24    const results = await dbService.getData();
25    data = { results };
26  } catch (err) {
27    console.error('Database error:', err);
28    data = { results: [], error: err instanceof Error ? err.message : 'Database error' };
29  }
30} else {
31  console.warn('Database not available in runtime');
32  data = { results: [], error: 'Database not available' };
33}
34---
35```
36 
37## Key Principles
38 
39- **Always check for db availability**: Database may not be available in all environments
40- **Use proper error handling**: Wrap database calls in try-catch blocks
41- **Log errors appropriately**: Console.error for debugging, user-friendly messages for UI
42- **Provide fallbacks**: Handle cases where database is unavailable gracefully
43- **Type safety**: Cast database connection with proper TypeScript types
44 
45## Service Layer Pattern
46 
47- Use service classes (like `OptionsService`, `DatabaseService`) to encapsulate database logic
48- Pass database connection to service instances
49- Keep database queries out of component frontmatter - delegate to services
50 
51## Error Handling Strategy
52 
53```astro
54---
55// Individual try-catch for each operation
56let snapshotsData: { snapshots: any[]; error?: string } = { snapshots: [] };
57let performanceData: { data: any[]; error?: string } = { data: [] };
58 
59if (db) {
60  try {
61    const service = SomeService.getInstance(db);
62    
63    // Separate error handling for each operation
64    try {
65      const snapshots = await service.getSnapshots();
66      snapshotsData = { snapshots };
67    } catch (err) {
68      snapshotsData = { snapshots: [], error: err instanceof Error ? err.message : 'Snapshots error' };
69    }
70    
71    try {
72      const performance = await service.getPerformance();
73      performanceData = { data: performance };
74    } catch (err) {
75      performanceData = { data: [], error: err instanceof Error ? err.message : 'Performance error' };
76    }
77  } catch (err) {
78    console.error('Service initialization error:', err);
79  }
80}
81---
82```