Instance-Aware Database Configuration Example

This example demonstrates the new instance-aware environment variable configuration system for multiple database connections.

Features Demonstrated

• Multiple database connections (primary, secondary, cache)
• Instance-specific environment variable mapping
• Automatic configuration from environment variables
• Consistent naming convention

Environment Variables

The example uses the following environment variable pattern:

DB_<INSTANCE>_<FIELD>=<VALUE>

For example:

• DB_PRIMARY_DRIVER=sqlite
• DB_PRIMARY_DSN=./primary.db
• DB_SECONDARY_DRIVER=sqlite
• DB_SECONDARY_DSN=./secondary.db
• DB_CACHE_DRIVER=sqlite
• DB_CACHE_DSN=:memory:

Running the Example

go run main.go

The example will:

1. Set up environment variables programmatically
2. Initialize the modular application with database module
3. Demonstrate multiple database connections
4. Show how each connection is configured independently
5. Clean up resources

Key Benefits

1. Separation of Concerns: Each database instance has its own environment variables
2. No Conflicts: Different database connections don't interfere with each other
3. Consistent Naming: Predictable environment variable names
4. Easy Configuration: Simple to set up in different environments
5. Automatic Mapping: No manual configuration code needed