diplonat/src/config/options.rs

use anyhow::Result;
use serde::Deserialize;

use crate::config::RuntimeConfig;

// This code is inspired by the Trunk crate (https://github.com/thedodd/trunk)

// This file parses the options that can be declared in the environment.
// runtime.rs applies business logic and builds RuntimeConfig structs.

// - Note for the future -
// There is no *need* to have a 'DIPLONAT_XXX_*' prefix for all config options.
// If some config options are shared by several modules, a ConfigOptsBase could
// contain them, and parse the 'DIPLONAT_*' prefix directly.
// Only in runtime.rs would these options find their proper location in each
// module's struct.

/// Consul configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsConsul {
  /// Consul's node name [default: None]
  pub node_name: Option<String>,
  /// Consul's REST URL [default: "http://127.0.0.1:8500"]
  pub url: Option<String>,
}

/// ACME configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsAcme {
  /// Whether the ACME module is enabled [default: false]
  #[serde(default)]
  pub enable: bool,

  /// The default domain holder's e-mail [default: None]
  pub email: Option<String>,
}

/// Firewall configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsFirewall {
  /// Whether the firewall module is enabled [default: false]
  #[serde(default)]
  pub enable: bool,

  /// Refresh time for firewall rules [default: 300]
  pub refresh_time: Option<u16>,
}

/// IGD configuration options
#[derive(Clone, Default, Deserialize)]
pub struct ConfigOptsIgd {
  /// Whether the IGD module is enabled [default: false]
  #[serde(default)]
  pub enable: bool,

  /// This node's private IP address [default: None]
  pub private_ip: Option<String>,
  /// Expiration time for IGD rules [default: 60]
  pub expiration_time: Option<u16>,
  /// Refresh time for IGD rules [default: 300]
  pub refresh_time: Option<u16>,
}

/// Model of all potential configuration options
pub struct ConfigOpts {
  pub consul: ConfigOptsConsul,
  pub acme: ConfigOptsAcme,
  pub firewall: ConfigOptsFirewall,
  pub igd: ConfigOptsIgd,
}

impl ConfigOpts {
  pub fn from_env() -> Result<RuntimeConfig> {
    let consul: ConfigOptsConsul = envy::prefixed("DIPLONAT_CONSUL_").from_env()?;
    let acme: ConfigOptsAcme = envy::prefixed("DIPLONAT_ACME_").from_env()?;
    let firewall: ConfigOptsFirewall = envy::prefixed("DIPLONAT_FIREWALL_").from_env()?;
    let igd: ConfigOptsIgd = envy::prefixed("DIPLONAT_IGD_").from_env()?;

    RuntimeConfig::new(Self {
      consul,
      acme,
      firewall,
      igd,
    })
  }

  // Currently only used in tests
  #[allow(dead_code)]
  pub fn from_iter<Iter: Clone>(iter: Iter) -> Result<RuntimeConfig>
  where
    Iter: IntoIterator<Item = (String, String)>,
  {
    let consul: ConfigOptsConsul = envy::prefixed("DIPLONAT_CONSUL_").from_iter(iter.clone())?;
    let acme: ConfigOptsAcme = envy::prefixed("DIPLONAT_ACME_").from_iter(iter.clone())?;
    let firewall: ConfigOptsFirewall =
      envy::prefixed("DIPLONAT_FIREWALL_").from_iter(iter.clone())?;
    let igd: ConfigOptsIgd = envy::prefixed("DIPLONAT_IGD_").from_iter(iter.clone())?;

    RuntimeConfig::new(Self {
      consul,
      acme,
      firewall,
      igd,
    })
  }
}