foxhunt/config/examples/runtime_config_example.rs

//! Runtime Configuration Example
//!
//! Demonstrates how to use the RuntimeConfig layer with environment-aware defaults.

use config::runtime::{Environment, RuntimeConfig};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    println!("=== Foxhunt Runtime Configuration Example ===\n");

    // Example 1: Auto-detect environment from ENVIRONMENT variable
    println!("1. Auto-detecting environment:");
    let config = RuntimeConfig::from_env()?;
    println!("   Environment: {:?}", config.environment);
    println!("   Database query timeout: {:?}", config.database.query_timeout);
    println!("   Position cache TTL: {:?}", config.cache.position_ttl);
    println!("   gRPC request timeout: {:?}", config.timeouts.grpc_request_timeout);
    println!("   ML max batch size: {}", config.limits.ml_max_batch_size);
    println!();

    // Example 2: Development environment defaults
    println!("2. Development environment defaults:");
    let dev_config = RuntimeConfig::with_defaults(Environment::Development);
    println!("   Database query timeout: {:?} (relaxed for debugging)", dev_config.database.query_timeout);
    println!("   Position cache TTL: {:?} (longer for debugging)", dev_config.cache.position_ttl);
    println!("   Safety check timeout: {:?} (relaxed)", dev_config.limits.safety_check_timeout);
    println!();

    // Example 3: Production environment defaults
    println!("3. Production environment defaults:");
    let prod_config = RuntimeConfig::with_defaults(Environment::Production);
    println!("   Database query timeout: {:?} (tight for HFT)", prod_config.database.query_timeout);
    println!("   Position cache TTL: {:?} (short for HFT)", prod_config.cache.position_ttl);
    println!("   Safety check timeout: {:?} (aggressive)", prod_config.limits.safety_check_timeout);
    println!();

    // Example 4: Staging environment (middle ground)
    println!("4. Staging environment defaults:");
    let staging_config = RuntimeConfig::with_defaults(Environment::Staging);
    println!("   Database query timeout: {:?}", staging_config.database.query_timeout);
    println!("   Position cache TTL: {:?}", staging_config.cache.position_ttl);
    println!("   Safety check timeout: {:?}", staging_config.limits.safety_check_timeout);
    println!();

    // Example 5: Validation
    println!("5. Configuration validation:");
    match config.validate() {
        Ok(_) => println!("   ✓ Configuration is valid"),
        Err(e) => println!("   ✗ Configuration error: {}", e),
    }
    println!();

    // Example 6: Environment variable override (simulated)
    println!("6. Environment variable overrides:");
    println!("   Set DATABASE_QUERY_TIMEOUT_MS=500 to override query timeout");
    println!("   Set CACHE_POSITION_TTL_SECS=30 to override position cache TTL");
    println!("   Set ML_MAX_BATCH_SIZE=16384 to override ML batch size");
    println!("   Set RISK_VAR_CONFIDENCE=0.99 to override VaR confidence");
    println!();

    // Example 7: Comparing environments
    println!("7. Environment comparison (timeouts in ms):");
    println!("   Configuration           | Development | Staging | Production");
    println!("   ----------------------- | ----------- | ------- | ----------");
    println!("   DB Query Timeout        | {:>11} | {:>7} | {:>10}",
        dev_config.database.query_timeout.as_millis(),
        staging_config.database.query_timeout.as_millis(),
        prod_config.database.query_timeout.as_millis());
    println!("   Safety Check Timeout    | {:>11} | {:>7} | {:>10}",
        dev_config.limits.safety_check_timeout.as_millis(),
        staging_config.limits.safety_check_timeout.as_millis(),
        prod_config.limits.safety_check_timeout.as_millis());
    println!("   ML Inference Timeout    | {:>11} | {:>7} | {:>10}",
        dev_config.limits.ml_inference_timeout.as_millis(),
        staging_config.limits.ml_inference_timeout.as_millis(),
        prod_config.limits.ml_inference_timeout.as_millis());
    println!();

    // Example 8: Cache TTLs (in seconds)
    println!("8. Cache TTL comparison (seconds):");
    println!("   Cache Type         | Development | Staging | Production");
    println!("   ------------------ | ----------- | ------- | ----------");
    println!("   Position Cache     | {:>11} | {:>7} | {:>10}",
        dev_config.cache.position_ttl.as_secs(),
        staging_config.cache.position_ttl.as_secs(),
        prod_config.cache.position_ttl.as_secs());
    println!("   VaR Cache          | {:>11} | {:>7} | {:>10}",
        dev_config.cache.var_ttl.as_secs(),
        staging_config.cache.var_ttl.as_secs(),
        prod_config.cache.var_ttl.as_secs());
    println!("   Market Data Cache  | {:>11} | {:>7} | {:>10}",
        dev_config.cache.market_data_ttl.as_secs(),
        staging_config.cache.market_data_ttl.as_secs(),
        prod_config.cache.market_data_ttl.as_secs());
    println!();

    println!("=== Example Complete ===");

    Ok(())
}