# Work Summary: .env Configuration Implementation
**Date:** 2026-01-12
**Status:** ✅ Complete

## Overview
Updated the Attune API to use `.env` file-based configuration with support for JWT settings, making it easier to configure and run the service locally.

## Changes Made

### 1. Updated SecurityConfig in Common Crate
**File:** `crates/common/src/config.rs`

- Split `jwt_expiration` into two separate fields:
  - `jwt_access_expiration` - Access token lifetime (default: 3600s / 1 hour)
  - `jwt_refresh_expiration` - Refresh token lifetime (default: 604800s / 7 days)
- Added default functions for both expiration settings
- Updated Default implementation for SecurityConfig
- Updated test cases to use new field names

### 2. Updated API Main Entry Point
**File:** `crates/api/src/main.rs`

**Before:**
- Read JWT settings from individual environment variables (`JWT_SECRET`, `JWT_ACCESS_EXPIRATION`, `JWT_REFRESH_EXPIRATION`)
- Manual fallback to defaults

**After:**
- Added `.env` file loading using `dotenvy` (already a dependency)
- Priority: `.env.local` > `.env` > environment variables
- Load JWT configuration from `Config.security` struct
- Use structured configuration instead of individual env vars
- Added informative logging showing token expiration times

Key changes:
```rust
// Load .env file automatically
if let Ok(_) = dotenvy::from_filename(".env.local") {
    info!("Loaded configuration from .env.local");
} else if let Ok(_) = dotenvy::dotenv() {
    info!("Loaded configuration from .env");
}

// Use config values instead of env vars
let jwt_secret = config.security.jwt_secret.clone().unwrap_or_else(|| {
    tracing::warn!("JWT_SECRET not set in config, using default (INSECURE for production!)");
    "insecure_default_secret_change_in_production".to_string()
});

let jwt_config = JwtConfig {
    secret: jwt_secret,
    access_token_expiration: config.security.jwt_access_expiration as i64,
    refresh_token_expiration: config.security.jwt_refresh_expiration as i64,
};
```

### 3. Updated .env.example
**File:** `.env.example`

- Changed `ATTUNE__SECURITY__JWT_EXPIRATION` to `ATTUNE__SECURITY__JWT_ACCESS_EXPIRATION`
- Added `ATTUNE__SECURITY__JWT_REFRESH_EXPIRATION` with 7-day default
- Updated comments to clarify access vs refresh tokens

### 4. Created Default .env File
**File:** `.env` (new)

Created a simple, ready-to-use configuration file with:
- Database connection to local PostgreSQL
- JWT secret for development
- Access token: 1 hour (3600s)
- Refresh token: 7 days (604800s)
- Server on 127.0.0.1:8080
- Pretty log format for development
- All essential settings for quick start

### 5. Created Quick Start Guide
**File:** `docs/quick-start.md` (new)

Comprehensive guide including:
- Step-by-step database setup
- Configuration instructions
- How to start the API
- Testing examples
- Common customizations
- Troubleshooting tips
- Production deployment checklist

## Configuration Format

The API now uses the following environment variable format:

```bash
# Double underscore for nested config
ATTUNE__SECURITY__JWT_SECRET=your-secret-here
ATTUNE__SECURITY__JWT_ACCESS_EXPIRATION=3600
ATTUNE__SECURITY__JWT_REFRESH_EXPIRATION=604800
ATTUNE__DATABASE__URL=postgresql://user:pass@host:port/db
```

## Benefits

1. **Easier Local Development**
   - No need to export multiple environment variables
   - Single `.env` file contains all configuration
   - Copy `.env.example` to `.env` and start coding

2. **Better Organization**
   - All config in one place
   - Structured configuration with validation
   - Type-safe with Rust's type system

3. **Flexible Configuration**
   - Support for `.env.local` for personal overrides
   - Environment variables still work (higher priority)
   - Config files via `ATTUNE_CONFIG` environment variable

4. **Production Ready**
   - Clear separation of dev/prod settings
   - JWT secrets properly configurable
   - Validation ensures required settings are present

## Usage

### For Development

1. **Quick Start:**
   ```bash
   cd attune
   ./scripts/setup-db.sh
   cargo run --bin attune-api
   ```
   That's it! The `.env` file is already configured.

2. **Custom Settings:**
   ```bash
   # Create personal overrides
   cp .env .env.local
   # Edit .env.local with your settings
   # .env.local takes priority
   ```

### For Production

1. **Don't use .env files** - Use