plan-forge multi-environment.instructions.md

Multi-Environment Configuration (.NET)

Environment Hierarchy

Configuration Loading Order

appsettings.json                  ← Base (all environments)
appsettings.{Environment}.json    ← Environment-specific overrides
Environment variables             ← Infrastructure overrides (highest priority)
User secrets (dev only)           ← Local developer secrets

Rules

• NEVER put secrets in appsettings.json — use User Secrets (dev) or Key Vault (prod)
• NEVER hardcode environment-specific URLs — use config per environment
• ALWAYS have a base appsettings.json with sensible defaults
• ALWAYS use IOptions<T> / IOptionsSnapshot<T> for typed config
• Environment variables override JSON settings (12-factor app)

Per-Environment Settings

// appsettings.Development.json
{
  "ConnectionStrings": {
    "Database": "Host=localhost;Port=5432;Database=contoso_dev;Username=dev;Password=devpass"
  },
  "Logging": { "LogLevel": { "Default": "Debug" } },
  "Cors": { "Origins": ["http://localhost:3000", "http://localhost:5173"] }
}

// appsettings.Staging.json
{
  "ConnectionStrings": {
    "Database": "Host=staging-db;Port=5432;Database=contoso_staging"
  },
  "Logging": { "LogLevel": { "Default": "Information" } },
  "Cors": { "Origins": ["https://staging.contoso.com"] }
}

// appsettings.Production.json
{
  "ConnectionStrings": {
    "Database": "" // Injected via environment variable or Key Vault
  },
  "Logging": { "LogLevel": { "Default": "Warning" } },
  "Cors": { "Origins": ["https://contoso.com", "https://www.contoso.com"] }
}