Configuration

Azu provides a comprehensive configuration system for managing application settings, environment-specific values, and runtime behavior.

Azu::Configuration

The main configuration class for Azu applications.

Properties

port : Int32

Server port number (default: 3000).

Azu.configure do |config|
  config.port = 8080
end

host : String

Server host address (default: "0.0.0.0").

Azu.configure do |config|
  config.host = "localhost"
end

environment : String

Application environment (default: "development").

Azu.configure do |config|
  config.environment = "production"
end

debug : Bool

Enable debug mode (default: false).

Azu.configure do |config|
  config.debug = true
end

ssl : Bool

Enable SSL/TLS (default: false).

Azu.configure do |config|
  config.ssl = true
end

ssl_cert : String?

Path to SSL certificate file.

Azu.configure do |config|
  config.ssl_cert = "/path/to/cert.pem"
end

ssl_key : String?

Path to SSL private key file.

Azu.configure do |config|
  config.ssl_key = "/path/to/key.pem"
end

Environment Configuration

Development Environment

if Azu::Environment.development?
  Azu.configure do |config|
    config.debug = true
    config.port = 3000
  end
end

Production Environment

if Azu::Environment.production?
  Azu.configure do |config|
    config.debug = false
    config.port = 80
    config.ssl = true
  end
end

Environment Variables

Azu.configure do |config|
  config.port = ENV["PORT"]?.try(&.to_i) || 3000
  config.host = ENV["HOST"]? || "0.0.0.0"
  config.environment = ENV["ENVIRONMENT"]? || "development"
  config.debug = ENV["DEBUG"]? == "true"
end

Database Configuration

Database URL

Azu.configure do |config|
  config.database_url = ENV["DATABASE_URL"]? || "sqlite3://./app.db"
end

Connection Pool

Azu.configure do |config|
  config.database_pool_size = 10
  config.database_pool_timeout = 5.seconds
end

Cache Configuration

Redis Configuration

Azu.configure do |config|
  config.redis_url = ENV["REDIS_URL"]? || "redis://localhost:6379"
  config.redis_pool_size = 5
end

Memory Cache

Azu.configure do |config|
  config.cache_type = :memory
  config.cache_size = 1000
  config.cache_ttl = 1.hour
end

Logging Configuration

Log Level

Azu.configure do |config|
  config.log_level = :info
end

Log Format

Azu.configure do |config|
  config.log_format = :json
end

Log File

Azu.configure do |config|
  config.log_file = "/var/log/azu/app.log"
end

Security Configuration

CORS Settings

Azu.configure do |config|
  config.cors_origins = ["http://localhost:3000", "https://example.com"]
  config.cors_methods = ["GET", "POST", "PUT", "DELETE"]
  config.cors_headers = ["Content-Type", "Authorization"]
  config.cors_credentials = true
end

CSRF Protection

Azu.configure do |config|
  config.csrf_secret = ENV["CSRF_SECRET"]? || "your-secret-key"
  config.csrf_token_header = "X-CSRF-Token"
end

Rate Limiting

Azu.configure do |config|
  config.rate_limit_requests = 100
  config.rate_limit_window = 1.minute
  config.rate_limit_storage = :memory
end

Template Configuration

Template Directory

Azu.configure do |config|
  config.template_directory = "src/templates"
end

Template Engine

Azu.configure do |config|
  config.template_engine = :jinja2
end

Hot Reload

Azu.configure do |config|
  config.template_hot_reload = Azu::Environment.development?
end

WebSocket Configuration

WebSocket Settings

Azu.configure do |config|
  config.websocket_timeout = 30.seconds
  config.websocket_max_connections = 1000
end

Channel Configuration

Azu.configure do |config|
  config.channel_prefix = "/ws"
  config.channel_authentication = true
end

Performance Configuration

Worker Threads

Azu.configure do |config|
  config.worker_threads = 4
end

Request Timeout

Azu.configure do |config|
  config.request_timeout = 30.seconds
end

Response Compression

Azu.configure do |config|
  config.compression = true
  config.compression_level = 6
end

Monitoring Configuration

Metrics

Azu.configure do |config|
  config.metrics_enabled = true
  config.metrics_port = 9090
end

Health Checks

Azu.configure do |config|
  config.health_check_path = "/health"
  config.health_check_interval = 10.seconds
end

Configuration Files

YAML Configuration

# config/development.yml
port: 3000
host: localhost
debug: true
database_url: sqlite3://./app.db

# Load YAML configuration
config = YAML.parse(File.read("config/development.yml"))
Azu.configure do |c|
  c.port = config["port"].as_i
  c.host = config["host"].as_s
  c.debug = config["debug"].as_bool
  c.database_url = config["database_url"].as_s
end

JSON Configuration

{
  "port": 3000,
  "host": "localhost",
  "debug": true,
  "database_url": "sqlite3://./app.db"
}

# Load JSON configuration
config = JSON.parse(File.read("config/development.json"))
Azu.configure do |c|
  c.port = config["port"].as_i
  c.host = config["host"].as_s
  c.debug = config["debug"].as_bool
  c.database_url = config["database_url"].as_s
end

Configuration Validation

Required Settings

Azu.configure do |config|
  config.port = ENV["PORT"]?.try(&.to_i) || raise "PORT environment variable is required"
  config.database_url = ENV["DATABASE_URL"]? || raise "DATABASE_URL environment variable is required"
end

Setting Validation

Azu.configure do |config|
  config.port = ENV["PORT"]?.try(&.to_i) || 3000
  raise "Port must be between 1 and 65535" unless (1..65535).includes?(config.port)
end

Configuration Inheritance

Base Configuration

# config/base.cr
module BaseConfig
  def self.configure
    Azu.configure do |config|
      config.host = "0.0.0.0"
      config.debug = false
    end
  end
end

Environment-specific Configuration

# config/development.cr
module DevelopmentConfig
  def self.configure
    BaseConfig.configure

    Azu.configure do |config|
      config.debug = true
      config.port = 3000
    end
  end
end

Configuration Testing

Test Configuration

# spec/spec_helper.cr
Azu.configure do |config|
  config.port = 0  # Random port for testing
  config.debug = false
  config.database_url = "sqlite3://:memory:"
end

Configuration Validation Tests

describe "Configuration" do
  it "validates required settings" do
    expect_raises(ArgumentError) do
      Azu.configure do |config|
        config.port = 0  # Invalid port
      end
    end
  end
end

Next Steps

• Learn about Error Handling

• Explore Performance Optimization

• Understand Environment Management

• See Security Best Practices