zirv-config

zirv-config is an expandable configuration library for Rust backend applications. It provides a global, mutable configuration store that aggregates settings from multiple subsystems (e.g. server, logging, etc.). Developers can register configuration blocks under namespaces, and later retrieve or update the configuration using convenient macros.

Features

• Global Configuration Store:
  The configuration is maintained as a JSON object in a global store. This store is expandable—subsystems can register their configuration data under a unique namespace.

• Environment Integration:
  Automatically loads environment variables (and optionally a .env file via dotenvy) to initialize configuration values.

• Dynamic Registration:
  Easily register new configuration blocks using the register_config! macro.

• Flexible Access:
  Retrieve the entire configuration or a specific configuration value by using dot-separated keys with the read_config! macro.

• Runtime Updates:
  Update configuration values at runtime using the write_config! macro.
  (Note: At present, the write functionality can be added by modifying the global store.)

Installation

Add zirv-config as a dependency in your project's Cargo.toml:

cargo add zirv-config

Usage

Before using the macros, initialize the global configuration store. In your application’s startup code, call:

// Initialize the global configuration
zirv_config::config::init_config();

Registering Configuration Blocks

Register a configuration block under a namespace (for example, "server") using the provided register_config! macro. Any type that implements Serialize can be used.

use zirv_config::register_config;
use serde::Serialize;

#[derive(Serialize)]
struct ServerConfig {
    port: u16,
    host: String,
}

fn main() {
    // Ensure the configuration store is initialized
    zirv_config::config::init_config();

    // Register your server configuration
    let server_config = ServerConfig { port: 3000, host: "0.0.0.0".into() };
    register_config!("server", server_config);
}

Reading Configuration Values

Retrieve the full configuration or a specific key using the read_config! macro. You can also request to deserialize a particular value into a desired type.

use zirv_config::read_config;

fn display_config() {
    // Retrieve the full configuration as a serde_json::Value
    let full_config = read_config!();
    println!("Full config: {:?}", full_config);

    // Get a specific configuration value as JSON
    if let Some(port) = read_config!("server.port") {
        println!("Server port (JSON): {}", port);
    }

    // Get a specific configuration value and convert it to the desired type
    if let Some(port) = read_config!("server.port", u16) {
        println!("Server port as u16: {}", port);
    }
}

License

This project is licensed under the MIT license.

Contributing

Contributions are welcome! Please refer to the contributing guidelines for more information.