Use environment variables instead of config file

2 files changed, 44 insertions, 28 deletions

diff --git a/src/main.rs b/src/main.rs
index 74917a9..65d52df 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,9 +1,7 @@
-use clap::Parser;
 use hyper::service::{make_service_fn, service_fn};
 use hyper::Server;
 use sqlx::sqlite::SqlitePool;
 use std::convert::Infallible;
-use std::net::SocketAddr;
 
 #[macro_use]
 extern crate log;
@@ -22,20 +20,7 @@ mod templates;
 mod utils;
 mod validation;
 
-use model::config::Config;
-
-#[derive(Parser)]
-#[clap()]
-struct Args {
-    #[clap(short, long, default_value = "0.0.0.0:3000")]
-    address: SocketAddr,
-
-    #[clap(short, long, default_value = "config.json")]
-    config: String,
-
-    #[clap(short, long, default_value = "database.db")]
-    database: String,
-}
+use model::config;
 
 #[tokio::main]
 async fn main() {
@@ -44,13 +29,10 @@ async fn main() {
     )
     .init();
 
-    let args = Args::parse();
-
-    let config_str = std::fs::read_to_string(&args.config)
-        .unwrap_or_else(|_| panic!("{}", format!("Missing {}", args.config)));
-    let config: Config = serde_json::from_str(&config_str).unwrap();
+    let config = config::from_env()
+        .unwrap_or_else(|err| panic!("Error reading config: {err}"));
 
-    let pool = SqlitePool::connect(&format!("sqlite:{}", args.database))
+    let pool = SqlitePool::connect(&format!("sqlite:{}", config.db_path))
         .await
         .unwrap();
 
@@ -78,8 +60,8 @@ async fn main() {
         }
     });
 
-    info!("Starting server at {}", args.address);
-    if let Err(e) = Server::bind(&args.address).serve(make_svc).await {
+    info!("Starting server at {}", config.socket_address);
+    if let Err(e) = Server::bind(&config.socket_address).serve(make_svc).await {
         error!("server error: {}", e);
     }
 }
diff --git a/src/model/config.rs b/src/model/config.rs
index e69b4c4..1fa5bb4 100644
--- a/src/model/config.rs
+++ b/src/model/config.rs
@@ -1,8 +1,42 @@
-use serde::Deserialize;
+use std::env;
+use std::net::SocketAddr;
+use std::str::FromStr;
 
-#[derive(Clone, Deserialize)]
+#[derive(Clone)]
 pub struct Config {
-    pub secure_cookies: bool,
-    pub mock_mails: bool,
     pub auth_secret: String,
+    pub db_path: String,
+    pub mock_mails: bool,
+    pub secure_cookies: bool,
+    pub socket_address: SocketAddr,
+}
+
+pub fn from_env() -> Result<Config, String> {
+    Ok(Config {
+        auth_secret: read_string("AUTH_SECRET")?,
+        db_path: read_string("DB_PATH")?,
+        mock_mails: read_bool("MOCK_MAILS")?,
+        secure_cookies: read_bool("SECURE_COOKIES")?,
+        socket_address: read_socket_address("SOCKET_ADDRESS")?,
+    })
+}
+
+fn read_socket_address(key: &str) -> Result<SocketAddr, String> {
+    SocketAddr::from_str(&read_string(key)?).map_err(|err| {
+        format!("environment variable '{key}' is not a socket address: {err}")
+    })
+}
+
+fn read_bool(key: &str) -> Result<bool, String> {
+    read_string(key).and_then(|v| match v.as_str() {
+        "true" => Ok(true),
+        "false" => Ok(false),
+        _ => Err(format!(
+            "environment variable '{key}' is not a boolean: '{v}'"
+        )),
+    })
+}
+
+fn read_string(key: &str) -> Result<String, String> {
+    env::var(key).map_err(|_| format!("missing environment variable '{key}'"))
 }