+//! # Configuration
+//!
+//! This module defines the configuration used to initialize both proxies.
+
+use log::error;
use std::env;
+use std::fmt::Debug;
use std::sync::Arc;
+use thiserror::Error;
+
+#[derive(Error, Debug)]
+pub enum Error {
+ #[error("Environment variable {0} not set.")]
+ MissingEnvVar(String),
+ #[error("Failed to parse {0}.")]
+ ParseError(String),
+}
-pub struct ProxyConfiguration {
+/// Configuration for any proxy
+#[derive(Debug)]
+pub struct Proxy {
pub local_port: u16,
- pub remote_domain: String,
+ pub bind_address: String,
+ pub remote_host: String,
pub remote_port: u16,
pub protocol: &'static str,
}
+/// Aggregated configuration for both proxies, already in a reference counter.
pub struct Configuration {
- pub imap_configuration: Arc<ProxyConfiguration>,
- pub smtp_configuration: Arc<ProxyConfiguration>,
+ pub imap_configuration: Arc<Proxy>,
+ pub smtp_configuration: Arc<Proxy>,
}
impl Configuration {
- pub fn new() -> Self {
- Configuration {
- imap_configuration: Arc::new(ProxyConfiguration {
- local_port: env::var("LOCAL_IMAP_PORT")
- .expect("LOCAL_IMAP_PORT not set")
- .parse()
- .expect("Invalid LOCAL_IMAP_PORT"),
- remote_domain: env::var("REMOTE_IMAP_DOMAIN").expect("REMOTE_IMAP_DOMAIN not set"),
- remote_port: env::var("REMOTE_IMAP_PORT")
- .expect("REMOTE_IMAP_PORT not set")
- .parse()
- .expect("Invalid REMOTE_IMAP_PORT"),
+ /// Creates a new configuration object by reading the environment
+ /// variables. Exits if the right ones aren't found.
+ pub fn new() -> Result<Self, Error> {
+ Ok(Configuration {
+ imap_configuration: Arc::new(Proxy {
+ local_port: get_env_number("LOCAL_IMAP_PORT", 143)?,
+ bind_address: get_env_var("LOCAL_IMAP_BIND_ADDRESS", Some("0.0.0.0".to_string()))?,
+ remote_host: get_env_var("REMOTE_IMAP_DOMAIN", None)?,
+ remote_port: get_env_number("REMOTE_IMAP_PORT", 993)?,
protocol: "IMAP",
}),
- smtp_configuration: Arc::new(ProxyConfiguration {
- local_port: env::var("LOCAL_SMTP_PORT")
- .expect("LOCAL_SMTP_PORT not set")
- .parse()
- .expect("Invalid LOCAL_SMTP_PORT"),
- remote_domain: env::var("REMOTE_SMTP_DOMAIN").expect("REMOTE_SMTP_DOMAIN not set"),
- remote_port: env::var("REMOTE_SMTP_PORT")
- .expect("REMOTE_SMTP_PORT not set")
- .parse()
- .expect("Invalid REMOTE_SMTP_PORT"),
+ smtp_configuration: Arc::new(Proxy {
+ local_port: get_env_number("LOCAL_SMTP_PORT", 25)?,
+ bind_address: get_env_var("LOCAL_SMTP_BIND_ADDRESS", Some("0.0.0.0".to_string()))?,
+ remote_host: get_env_var("REMOTE_SMTP_DOMAIN", None)?,
+ remote_port: get_env_number("REMOTE_SMTP_PORT", 993)?,
protocol: "SMTP",
}),
- }
+ })
+ }
+}
+
+/// Get an environment variable or return an error.
+fn get_env_var(name: &str, default: Option<String>) -> Result<String, Error> {
+ match env::var(name) {
+ Ok(value) => Ok(value),
+ Err(_) => match default {
+ Some(default_value) => Ok(default_value),
+ None => Err(Error::MissingEnvVar(name.to_string())),
+ },
+ }
+}
+
+/// Get an environment variable and parse it as a number. Return a default
+/// if not set.
+fn get_env_number(name: &str, default: u16) -> Result<u16, Error> {
+ match env::var(name) {
+ Ok(value) => value
+ .parse()
+ .map_err(|_| Error::ParseError(name.to_string())),
+ Err(_) => Ok(default),
}
}